Publishing type：Research paper (scientific journal)   Publisher：Japanese Society for Horticultural Science  

DOI： 10.2503/hrj.22.303

researchmap

DOI： 10.1101/2022.12.29.522208

researchmap

Publisher：Cold Spring Harbor Laboratory  

Summary

Multiplexed inter-simple sequence repeats genotyping by sequencing (MIG-seq) is an next-generation sequencing library construction method developed for the analysis of DNA in ecology. Although MIG-seq can generate libraries from low-quality DNA, few polymorphisms can be obtained in species with small genomes. In this study, we developed degenerate oligonucleotide primer MIG-seq (dpMIG-seq) as an effective polymorphism discovery method that allows for variation in the number of polymorphisms while retaining the advantages of MIG-seq, including independence from DNA quality. In dpMIG-seq, a proportion of the simple sequence repeats in the primer sequence of the first PCR in MIG-seq was changed to degenerate oligonucleotides to enable annealing to a wider range of sequences. In tests of several crop species other than wheat, the number of loci that could be sequenced using dpMIG-seq with a data volume of 0.3 gigabases (Gb) was increased compared with that sequenced using MIG-seq. In wheat, the number of polymorphisms obtained via dpMIG-seq was higher than that obtained via MIG-seq when a data volume of about ≥2 Gb was obtained. In dpMIG-seq, different loci could be sequenced by changing the positions of the degenerate oligonucleotides. By applying dpMIG-seq, we constructed a linkage map consisting of 5,142 markers for the rice inter-subspecies F₂ population, and we detected quantitative trait loci for heading date in the regions where known heading-related genes were located. Overall, our results show that dpMIG-seq is a useful tool for the genetic analysis of crop species.

DOI： 10.1101/2022.08.25.504752

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

In the evolutionary history of plants, variation in cis-regulatory elements (CREs) resulting in diversification of gene expression has played a central role in driving the evolution of lineage-specific traits. However, it is difficult to predict expression behaviors from CRE patterns to properly harness them, mainly because the biological processes are complex. In this study, we used cistrome datasets and explainable convolutional neural network (CNN) frameworks to predict genome-wide expression patterns in tomato (Solanum lycopersicum) fruit from the DNA sequences in gene regulatory regions. By fixing the effects of trans-acting factors using single cell-type spatiotemporal transcriptome data for the response variables, we developed a prediction model for crucial expression patterns in the initiation of tomato fruit ripening. Feature visualization of the CNNs identified nucleotide residues critical to the objective expression pattern in each gene, and their effects were validated experimentally in ripening tomato fruit. This cis-decoding framework will not only contribute to the understanding of the regulatory networks derived from CREs and transcription factor interactions, but also provides a flexible means of designing alleles for optimized expression.

DOI： 10.1093/plcell/koac079

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：International Society for Horticultural Science (ISHS)  

DOI： 10.17660/actahortic.2022.1338.49

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

In flowering plants, different lineages have independently transitioned from the ancestral hermaphroditic state into and out of various sexual systems1. Polyploidizations are often associated with this plasticity in sexual systems2,3. Persimmons (the genus Diospyros) have evolved dioecy via lineage-specific palaeoploidizations. More recently, hexaploid D. kaki has established monoecy and also exhibits reversions from male to hermaphrodite flowers in response to natural environmental signals (natural hermaphroditism, NH), or to artificial cytokinin treatment (artificial hermaphroditism, AH). We sought to identify the molecular pathways underlying these polyploid-specific reversions to hermaphroditism. Co-expression network analyses identified regulatory pathways specific to NH or AH transitions. Surprisingly, the two pathways appeared to be antagonistic, with abscisic acid and cytokinin signalling for NH and AH, respectively. Among the genes common to both pathways leading to hermaphroditic flowers, we identified a small-Myb RADIALIS-like gene, named DkRAD, which is specifically activated in hexaploid D. kaki. Consistently, ectopic overexpression of DkRAD in two model plants resulted in hypergrowth of the gynoecium. These results suggest that production of hermaphrodite flowers via polyploidization depends on DkRAD activation, which is not associated with a loss-of-function within the existing sex determination pathway, but rather represents a new path to (or reinvention of) hermaphroditism.

DOI： 10.1038/s41477-022-01107-z

PubMed

researchmap

Publishing type：Research paper (scientific journal)   Publisher：Elsevier {BV}  

DOI： 10.1016/j.postharvbio.2021.111787

researchmap

Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

Abstract

MIG-seq (Multiplexed inter-simple sequence repeats genotyping by sequencing) has been developed as a low cost genotyping technology, although the number of polymorphisms obtained is assumed to be minimal, resulting in the low application of this technique to analyses of agricultural plants. We applied MIG-seq to 12 plant species that include various crops and investigated the relationship between genome size and the number of bases that can be stably sequenced. The genome size and the number of loci, which can be sequenced by MIG-seq, are positively correlated. This is due to the linkage between genome size and the number of simple sequence repeats (SSRs) through the genome. The applicability of MIG-seq to population structure analysis, linkage mapping, and quantitative trait loci (QTL) analysis in wheat, which has a relatively large genome, was further evaluated. The results of population structure analysis for tetraploid wheat showed the differences among collection sites and subspecies, which agreed with previous findings. Additionally, in wheat biparental mapping populations, over 3,000 SNPs/indels with low deficiency were detected using MIG-seq, and the QTL analysis was able to detect recognized flowering-related genes. These results revealed the effectiveness of MIG-seq for genomic analysis of agricultural plants with large genomes, including wheat.

DOI： 10.1093/dnares/dsac011

researchmap

Other Link： https://academic.oup.com/dnaresearch/article-pdf/29/2/dsac011/43439343/dsac011.pdf

Publishing type：Research paper (scientific journal)  

In contrast to the progress in the research on physiological disorders relating to shelf life in fruit crops, it has been difficult to non-destructively predict their occurrence. Recent high-tech instruments have gradually enabled non-destructive predictions for various disorders in some crops, while there are still issues in terms of efficiency and costs. Here, we propose application of a deep neural network (or simply deep learning) to simple RGB images to predict a severe fruit disorder in persimmon, rapid over-softening. With 1,080 RGB images of ‘Soshu’ persimmon fruits, three convolutional neural networks (CNN) were examined to predict rapid over-softened fruits with a binary classification and the date to fruit softening. All of the examined CNN models worked successfully for binary classification of the rapid over-softened fruits and the controls with > 80% accuracy using multiple criteria. Furthermore, the prediction values (or confidence) in the binary classification were correlated to the date to fruit softening. Although the features for classification by deep learning have been thought to be in a black box by conventional standards, recent feature visualization methods (or “explainable” deep learning) has allowed identification of the relevant regions in the original images. We applied Grad-CAM, Guided backpropagation, and layer-wise relevance propagation (LRP), to find early symptoms for CNNs classification of rapid over-softened fruits. The focus on the relevant regions tended to be on color unevenness on the surface of the fruit, especially in the peripheral regions. These results suggest that deep learning frameworks could potentially provide new insights into early physiological symptoms of which researchers are unaware.

DOI： 10.2503/hortj.UTD-323

Scopus

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Peel degreening is the most conspicuous aspect of fruit ripening in many citrus fruits because of its importance for marketability. In this study, peel degreening in response to propylene (an ethylene analog) and at varying storage temperatures was characterized in Satsuma mandarin (Citrus unshiu Marc.) fruit. Propylene treatment triggered rapid peel degreening (within 4-6 days), indicated by an increase in the citrus color index (CCI) and chlorophyll loss. Peel degreening was also observed in fruit at 10°C and 15°C after 28-42 days, with gradual CCI increase and chlorophyll reduction. However, fruit at 5°C, 20°C, and 25°C remained green, and no substantial changes in peel CCI and chlorophyll content were recorded during the 42-day storage duration. The transcriptomes of peels of fruit treated with propylene for 4 days and those stored at varying temperatures for 28 days were then analyzed by RNA-Seq. We identified three categories of differentially expressed genes that were regulated by (i) propylene (and by analogy, ethylene) alone, (ii) low temperature (5°C, 10°C, or 15°C vs. 25°C) alone, and (iii) either propylene or low temperature. Gene-encoding proteins associated with chlorophyll degradation (such as CuSGR1, CuNOL, CuACD2, CuCAB2, and CuLHCB2) and a transcription factor (CuERF114) were differentially expressed by propylene or low temperature. To further examine temperature-induced pathways, we also monitored gene expression during on-tree fruit maturation vs. postharvest. The onset of on-tree peel degreening coincided with autumnal drops in field temperatures, and it was accompanied by differential expression of low temperature-regulated genes. On the contrary, genes that were exclusively regulated by propylene (such as CuCOPT1 and CuPOX-A2) displayed insignificant expression changes during on-tree peel degreening. These findings indicate that low temperatures could be involved in the fruit ripening-related peel degreening independently of ethylene.

DOI： 10.3389/fpls.2022.918226

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER  

During ripening, European pear (Pyrus communis L. cv. 'La France') fruit undergo dramatic softening in response to increased ethylene production, whereas Chinese pear (Pyrus bretschneideri Rehd. cv. 'Yali') fruit remain firm, despite producing large amounts of ethylene. The molecular basis of this differential softening behavior is not well understood. In this study, we combined a yeast-based signal sequence trap (YSST) and macroarray gene expression analysis to identify putative genes encoding secreted proteins that control pear fruit softening. We identified 22 cDNAs annotated as encoding proteins with diverse cell wall-associated functions that were upor down-regulated during fruit ripening in 'La France'. Gene expression analysis in fruit that were treated with the ethylene perception inhibitor 1-methylcyclopropene (1-MCP) at 4 d after the onset of ripening revealed that 16 of the targeted genes are ethylene-regulated, while the others appear to be ethylene independent. Comparative gene expression analyses of 'La France' and 'Yali' fruit during ripening suggested that four ethylene-regulated cDNAs encoding cell wall modifying proteins, contig 2 (polygalacturonase 3), contig 15 (expansin), contig 19 (expansin) and contig 55 (pectate lyase) contribute to the different softening behaviors of 'La France' and 'Yali' fruit. Additionally, one ethylene-independent cell wall related gene, contig 36 (expansin), and three genes encoding proteins of unknown function, contigs 1, 13 and contig 75 showed differential expression between 'La France' and 'Yali' fruit during ripening. The results presented herein represent promising candidates for future functional analysis and elucidation of softening mechanisms.

DOI： 10.1016/j.postharvbio.2020.111436

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Several citrus varieties show gametophytic self-incompatibility (GSI), which can contribute to seedless fruit production in several cultivars. This study investigated the genes regulating this trait through RNA-seq performed using styles collected from the flowers of Japanese citrus cultivars 'Hyuganatsu,' 'Tosabuntan,' 'Hassaku,' 'Banpeiyu,' and 'Sweet Spring'. We screened the transcripts of putative T2 RNases, i.e., the protein family including all S-RNases from S-RNase-based GSI plants, and constructed a phylogenetic tree using the screened T2 RNases and S-RNases retrieved from citrus genome databases and a public database. Three major clusters (class I-III) were formed, among which, the class III cluster contained family specific subclusters formed by S-RNase and a citrus-specific cluster monophyletic to the S-RNase clusters. From the citrus class III cluster, six transcripts were consistent with the S haplotypes previously determined in Japanese citrus accessions, sharing characteristics such as isoelectric point, extracellular localization, molecular weight, intron number and position, and tissue-specific expression with S-RNases. One T2 RNase gene in self-incompatible Hyuganatsu was significantly down-regulated in the styles of a self-compatible mutant of Hyuganatsu in RNA-seq and qPCR analyses. In addition, the inheritance pattern of some T2 RNase genes was consistent with the pattern of the S haplotype in the progeny population of Hyuganatsu and Tosabuntan. As all results supported citrus self-incompatibility being based on S-RNase, we believe that six T2 RNase genes were S-RNases. The homology comparison between the six T2 RNases and S-RNases recently reported in Chinese citrus revealed that three out of six T2 RNases were identical to S-RNases from Chinese citrus. Thus, the other three T2 RNases were finally concluded to be novel citrus S-RNases involved in self-incompatibility.

DOI： 10.3389/fpls.2021.638321

PubMed

researchmap

Publishing type：Research paper (scientific journal)   Publisher：Japanese Society for Horticultural Science  

DOI： 10.2503/hrj.20.455

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：FRONTIERS MEDIA SA  

Sex expression in plants is often flexible and contributes to the maintenance of genetic diversity within a species. In diploid persimmons (the genus Diospyros), the sexuality is controlled by the Y chromosome-encoded small-RNA gene, OGI, and its autosomal counterpart, MeGI. Hexaploid Oriental persimmon (Diospyros kaki) evolved more flexible sex expression, where genetically male individuals carrying OGI can produce both male and female flowers (monoecy). This is due to (semi-)inactivation of OGI by the Kali-SINE retrotransposon insertion on the promoter region and the resultant DNA methylations. Instead, flower sex determination in Oriental persimmon is also dependent on DNA methylation states of MeGI. Here, we focused on a cultivar, Kumemaru, which shows stable male flower production. Our results demonstrated that cv. Kumemaru carries OGI with Kali-SINE, which was highly methylated as well as in other monoecious cultivars; nevertheless, OGI gene could have a basal expression level. Transcriptomic analysis between cv. Kumemaru and 14 cultivars that predominantly produce female flowers showed differentially expressed genes (DEGs) specific to cv. Kumemaru, which is mainly involved in stress responses. Co-expression gene networks focusing on the DEGs also suggested the involvement of stress signals, mainly via gibberellin (GA), salicylic acid (SA), and especially jasmonic acid (JA) signal pathways. We also identified potential regulators of this co-expression module, represented by the TCP4 transcription factor. Furthermore, we attempted to identify cv. Kumemaru-specific transcript polymorphisms potentially contributing to derepressed OGI expression by cataloging subsequences (k-mers) in the transcriptomic reads from cv. Kumemaru and the other 14 female cultivars. Overall, although the direct genetic factor to activate OGI remains to be solved, our results implied the involvement of stress signals in the release of silenced OGI and the resultant continuous male production.

DOI： 10.3389/fpls.2020.567249

Web of Science

researchmap

Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

<title>Abstract</title>
Peel degreening is an important aspect of fruit ripening in many citrus fruit, and previous studies have shown that it can be advanced by ethylene treatment or by low-temperature storage. However, the important regulators and pathways involved in natural peel degreening remain largely unknown. To determine how natural peel degreening is regulated in lemon fruit (Citrus limon), we studied transcriptome and physiochemical changes in the flavedo in response to ethylene treatment and low temperatures. Treatment with ethylene induced rapid peel degreening, which was strongly inhibited by the ethylene antagonist, 1-methylcyclopropene (1-MCP). Compared with 25 ºC, moderately low storage temperatures of 5–20 °C also triggered peel degreening. Surprisingly, repeated 1-MCP treatments failed to inhibit the peel degreening induced by low temperature. Transcriptome analysis revealed that low temperature and ethylene independently regulated genes associated with chlorophyll degradation, carotenoid metabolism, photosystem proteins, phytohormone biosynthesis and signalling, and transcription factors. Peel degreening of fruit on trees occurred in association with drops in ambient temperature, and it coincided with the differential expression of low temperature-regulated genes. In contrast, genes that were uniquely regulated by ethylene showed no significant expression changes during on-tree peel degreening. Based on these findings, we hypothesize that low temperature plays a prominent role in regulating natural peel degreening independently of ethylene in citrus fruit.

DOI： 10.1093/jxb/eraa206

Web of Science

researchmap

Other Link： http://academic.oup.com/jxb/article-pdf/71/16/4778/33573305/eraa206.pdf

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

Sexuality is one of the fundamental mechanisms that work towards maintaining genetic diversity within a species. In diploid persimmons (Diospyros spp.), separated sexuality, the presence of separate male and female individuals (dioecy), is controlled by the Y chromosome-encoded small-RNA gene, OGI. On the other hand, sexuality in hexaploid Oriental persimmon (Diospyros kaki) is more plastic, with OGI-bearing genetically male individuals, able to produce both male and female flowers (monoecy). This is thought to be linked to the partial inactivation of OGI by a retrotransposon insertion, resulting in DNA methylation of the OGI promoter region. To identify the genetic factors regulating branch sexual conversion, genome-wide correlation/association analyses were conducted using ddRAD-Seq data from an F-1 segregating population, and using both quantitative and diploidized genotypes, respectively. We found that allelic ratio at the Y-chromosomal region, including OGI, was correlated with male conversion based on quantitative genotypes, suggesting that OGI can be activated in cis in a dosage-dependent manner. Genome-wide association analysis based on diploidized genotypes, normalized for the effect of OGI allele dosage, detected three fundamental loci associated with male conversion. These loci underlie candidate genes, which could potentially act epigenetically for the activation of OGI expression.

DOI： 10.1093/dnares/dsaa012

Web of Science

researchmap

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：THE JAPANESE SOCIETY FOR HORTICULTURAL SCIENCE  

Flesh texture of peach (Prunus persica (L.) Batsch) is one of the most important traits regarding post-harvest preservation and consumer preference. Melting flesh peaches show a typical climacteric type of ripening characterized by a burst of ethylene production and rapid loss of firmness in the late maturing stage. In contrast, stony hard peaches produce little ethylene and maintain flesh firmness on the tree and after harvest. Here, we demonstrated that ‘Tosui’ peach, which is selected from open-pollinated seedlings of ‘Kawanakajimahakuto’, bears stony hard characteristics. ‘Tosui’ peach shows a long shelf life and crisp flesh; however, its ethylene production and softening characteristics remain unclear. We investigated the change of ethylene production and flesh firmness of ‘Tosui’ peach treated with or without exogenous propylene, an ethylene analogue. In non-treated control fruit, little ethylene production was detected and marked flesh firmness was maintained irrespective of the harvest season and production area. Although the flesh firmness was significantly reduced by propylene treatment, little ethylene production was detected during fruit softening. Analysis of the PpYUC11 gene, a strong candidate for the stony hard phenotype in peaches, revealed that the genotype of the transposon insertion of the 5′-flanking region and simple sequence repeat (SSR) of the first intron of ‘Tosui’ is the same as that of other stony hard peaches. These results collectively suggest that ‘Tosui’ is a stony hard peach whose ethylene production and resulting loss of firmness are suppressed.

DOI： 10.2503/hrj.19.61

CiNii Article

CiNii Books

researchmap

Other Link： https://www.jstage.jst.go.jp/article/hrj/19/1/19_61/_pdf

Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

The postharvest properties of two ultra-late maturing peach cultivars, "Tobihaku" (TH) and "Daijumitsuto" (DJ), were investigated. Fruit were harvested at commercial maturity and held at 25°C. TH exhibited the characteristics of normal melting flesh (MF) peach, including rapid fruit softening associated with appropriate level of endogenous ethylene production In contrast, DJ did not soften at all during 3 weeks experimental period even though considerable ethylene production was observed. Fruit of TH and DJ were treated with 5,000 ppm of propylene, an ethylene analog, continuously for 7 days. TH softened rapidly whereas DJ maintained high flesh firmness in spite of an increase in endogenous ethylene production, suggesting that DJ but not TH lacked the ability to be softened in response to endogenous and exogenous ethylene/propylene. DNA-seq analysis showed that tandem endo-polygalacturonase (endoPG) genes located at melting flesh (M) locus, Pp-endoPGM (PGM), and Pp-endoPGF (PGF), were deleted in DJ. The endoPG genes at M locus are known to control flesh texture of peach fruit, and it was suggested that the non-softening property of DJ is due to the lack of endoPG genes. On the other hand, TH possessed an unidentified M haplotype that is involved in determination of MF phenotype. Structural identification of the unknown M haplotype, designated as M 0, through comparison with previously reported M haplotypes revealed distinct differences between PGM on M 0 haplotype (PGM-M0 ) and PGM on other haplotypes (PGM-M1 ). Peach M haplotypes were classified into four main haplotypes: M 0 with PGM-M0 ; M 1 with both PGM-M1 and PGF; M 2 with PGM-M1 ; and M 3 lacking both PGM and PGF. Re-evaluation of M locus in association with MF/non-melting flesh (NMF) phenotypes in more than 400 accessions by using whole genome shotgun sequencing data on database and/or by PCR genotyping demonstrated that M 0 haplotype was the common haplotype in MF accessions, and M 0 and M 1 haplotypes were dominant over M 2 and M 3 haplotypes and co-dominantly determined the MF trait. It was also assumed on the basis of structural comparison of M haplotypes among Prunus species that the ancestral haplotype of M 0 diverged from those of the other haplotypes before the speciation of Prunus persica.

DOI： 10.3389/fpls.2020.554158

PubMed

researchmap

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.postharvbio.2019.110949

researchmap

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYTOPATHOLOGICAL SOC  

Alternaria alternata is a generally saprophytic fungus. Its genome consists of 10 autosomes, while some strains have one or two additional chromosomes, called a conditionally dispensable chromosome (CDC). A CDC is not required for reproduction but confers hostspecific pathogenicity. We sequenced the genome of the peach pathotype of A. alternata using Nanopore and assembled it into 20 sequences. The 10 largest sequences corresponded to 10 gapless sequences of A. solani autosomes, and 1 sequence was a mitochondrial genome. Nine other sequences may be derived from CDCs because of lack of similarity with autosomes of other Alternaria spp. The sequence information could provide novel insights into genomes of Alternaria spp. and on the biosynthesis of a novel host-specific toxin in the peach pathotype of A. alternata.

DOI： 10.1094/MPMI-04-19-0093-A

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Frontiers Media SA  

Fruit ripening in response to propylene (an ethylene analog), 1-methylcyclopropene (1-MCP, an ethylene action inhibitor), and low temperature (5 degrees C) treatments was characterized in "Kosui" kiwifruit (Actinidia rufa x A. chinensis). Propylene treatment induced ethylene production, with increased expression levels of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase 1 (AcACS1) and ACC oxidase 2 (AcACO2), and rapid fruit softening together with increased expression levels of polygalacturonase (AcPG) and expansin 1 (AcEXP1) within 5 days (d). Fruit soluble solids concentration (SSC) and contents of sucrose, glucose, and fructose together with the expression levels of beta-amylase 1 (Ac beta-AMY1), Ac beta-AMY2, and invertase (AcINV3-1) increased rapidly after 5 d exposure to propylene. Furthermore, propylene exposure for 5 d was sufficient to induce the production of key aroma volatile compounds, ethyl- and methyl butanoate, accompanied with increased expression levels of alcohol acyl transferase (AcAAT). Application of 1-MCP at the start of the experiment, followed by continuous exposure to propylene, significantly delayed fruit softening, changes in SSC and sugars, and strongly suppressed the production of ethylene, aroma volatiles, and expression of associated genes. During storage, fruit softening, SSC and sugar increase, and increased expression of genes associated with cell wall modification and carbohydrate metabolism were registered without detectable ethylene production; however, these changes occurred faster at 5 degrees C compared to 22 degrees C. Interestingly, ethyl and methyl butanoate as well as AcAAT expression were undetectable in kiwifruit during storage, while they were rescued by post-storage propylene exposure, indicating that the production of aroma volatile compounds is strongly ethylene-dependent. Transcript levels of a NAC-related transcription factor (TF), AcNAC3, increased in response to both propylene and low temperature treatments, while AcNAC5 was exclusively up-regulated by propylene. By contrast, transcript levels of a MADS-box TF, AcMADS2, exclusively increased in response to low temperature. The above findings indicate that kiwifruit ripening is inducible by either ethylene or low temperature signals. However, fruit ripened by low temperature were deficient in ethylene-dependent aroma volatiles, suggesting that ethylene signaling is non-functional during low temperature-modulated ripening in kiwifruit. These data provide further evidence that ethylene-dependent and low temperature-modulated ripening in kiwifruit involve different regulatory mechanisms.

DOI： 10.3389/fpls.2019.00888

Web of Science

researchmap

Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

© 2018 Elsevier B.V. Kiwifruit exhibit a peculiar ripening pattern, as extensive softening is known to occur in the absence of any detectable ethylene. We previously demonstrated that this softening is regulated by low temperature independent of ethylene. However, there are no reports that provide comparisons of the ripening patterns among different kiwifruit cultivars at various storage temperatures. The purpose of this study was to compare the ripening responses and associated gene expression in ‘Sanuki Gold’ (Actinidia chinensis var. chinensis) and ‘Hayward’ ((Actinidia chinensis var. deliciosa) fruit, two kiwifruit cultivars differing in on–vine maturity dates and postharvest storability, during storage at 5 °C, 10 °C, 15 °C and 22 °C. Fruit softening, soluble solids concentration (SSC) increase and reduction of titratable acidity (TA) occurred in the absence of any detectable ethylene, and treatment with an ethylene inhibitor 1–methylcyclopropene (1–MCP) failed to suppress the changes, suggesting that they were independent of ethylene. ‘Sanuki Gold’ fruit showed a higher sensitivity to low temperature supported by accelerated fruit softening and TA reduction, and induction of several genes such as AcACO3, AcXET2, AcPG, AcEXP1, AcPMEi, AcGA2ox1, AcMADS2, AcNAC5 and AcbZIP2 at 5 °C, 10 °C and 15 °C within 28 d. By contrast, ‘Hayward’ fruit exhibited a lower sensitivity to low temperature as accelerated softening, TA reduction and induction of most ripening–associated genes were recorded only at 5 °C and 10 °C. These differences in sensitivity to low temperature, between ‘Sanuki Gold’ and ‘Hayward’ fruit, would account for the dissimilarities observed in on–vine maturity dates and postharvest storability.

DOI： 10.1016/j.postharvbio.2018.08.017

Web of Science

Scopus

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

Parthenocarpy, a process in which fruit set occurs without fertilization, leads to the production of seedless fruit. A number of floral homeotic mutants with abnormal stamen development exhibit parthenocarpic fruit set. Flower development is thought to repress ovary growth before anthesis. However, the mechanism of parthenocarpic fruit development caused by aberrant flower formation is poorly understood. To investigate the molecular mechanism of parthenocarpic fruit development in floral homeotic mutants, we performed functional analysis of Tomato APETALA3 (TAP3) by loss-of-function approaches. Organ-specific promoter was used to induce organ-specific loss of function in stamen and ovary/fruit. We observed increased cell expansion in tap3 mutants and TAP3-RNAi lines during parthenocarpic fruit growth. These were predominantly accompanied by the up-regulation of GA biosynthesis genes, including SlGA20ox1, SlGA20ox2, and SlGA20ox3, as well as reduced expression of the GA-inactivating gene SlGA2ox1 and the auxin signaling gene SlARF7 involved in a crosstalk between GA and auxin. These transcriptional profiles are in agreement with the GA levels in these lines. These results suggest th

DOI： 10.1093/pcp/pcy184

Web of Science

researchmap

Publishing type：Research paper (international conference proceedings)  

DOI： 10.17660/ActaHortic.2018.1218.71

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC HORTICULTURAL SCI  

Persimmon (Diospyros kaki) is a tree crop species that originated in East Asia, consists mainly of hexaploid individuals (2n = 6x = 90) with some nonaploid individuals. One of the unique characteristics of persimmon is the continuous accumulation of proanthocyanidins (PAs) in its fruit until the middle of fruit development, resulting in a strong astringent taste even at commercial fruit maturity. Among persimmon cultivars, pollination-constant and non-astringent (PCNA) types cease PA accumulation in early fruit development and become non-astringent at commercial maturity. PCNA is an allelic trait to non-PCNA and is controlled by a single locus called the ASTRINGENCY (AST) locus. Previous segregation analyses indicated that the AST locus shows hexasomic inheritance; a recessive allele, ast, at this locus confers PCNA. Here, we report a shuttle mapping approach to delimit the AST locus region in the hexaploid persimmon genome by using D. lotus, a diploid relative of D. kaki, as a reference. A D. lotus F-1 population of 333 individuals and 296 D. kaki siblings segregating for the PCNA trait were used to map the AST region using haplotype-specific markers covering the AST region. This indicated that the AST locus is syntenic to an approximately 915-kb region of the D. lotus genome. In this 915-kb region, we found several candidates for AST that were revealed from the fruit transcriptome of a population segregating for the PCNA trait. These results could provide important clues for the isolation of AST in hexaploid persimmon.

DOI： 10.2503/hortj.OKD-140

Web of Science

researchmap

Publishing type：Research paper (scientific journal)  

© 2018 The Author(s). Background: Kiwifruit are classified as climacteric since exogenous ethylene (or its analogue propylene) induces rapid ripening accompanied by ethylene production under positive feedback regulation. However, most of the ripening-associated changes (Phase 1 ripening) in kiwifruit during storage and on-vine occur largely in the absence of any detectable ethylene. This ripening behavior is often attributed to basal levels of system I ethylene, although it is suggested to be modulated by low temperature. Results: To elucidate the mechanisms regulating Phase 1 ripening in kiwifruit, a comparative transcriptome analysis using fruit continuously exposed to propylene (at 20 °C), and during storage at 5 °C and 20 °C was conducted. Propylene exposure induced kiwifruit softening, reduction of titratable acidity (TA), increase in soluble solids content (SSC) and ethylene production within 5 days. During storage, softening and reduction of TA occurred faster in fruit at 5 °C compared to 20 °C although no endogenous ethylene production was detected. Transcriptome analysis revealed 3761 ripening-related differentially expressed genes (DEGs), of which 2742 were up-regulated by propylene while 1058 were up-regulated by low temperature. Propylene exclusively up-regulated 2112 DEGs including those associated with ethylene biosynthesis and ripening such as AcACS1, AcACO2, AcPL1, AcXET1, Acβ-GAL, AcAAT, AcERF6 and AcNAC7. Similarly, low temperature exclusively up-regulated 467 DEGS including AcACO3, AcPL2, AcPMEi, AcADH, Acβ-AMY2, AcGA2ox2, AcNAC5 and AcbZIP2 among others. A considerable number of DEGs such as AcPG, AcEXP1, AcXET2, Acβ-AMY1, AcGA2ox1, AcNAC6, AcMADS1 and AcbZIP1 were up-regulated by either propylene or low temperature. Frequent 1-MCP treatments failed to inhibit the accelerated ripening and up-regulation of associated DEGs by low temperature indicating that the changes were independent of ethylene. On-vine kiwifruit ripening proceeded in the absence of any detectable endogenous ethylene production, and coincided with increased expression of low temperature-responsive DEGs as well as the decrease in environmental temperature. Conclusions: These results indicate that kiwifruit possess both ethylene-dependent and low temperature-modulated ripening mechanisms that are distinct and independent of each other. The current work provides a foundation for elaborating the control of these two ripening mechanisms in kiwifruit.

DOI： 10.1186/s12870-018-1264-y

Web of Science

Scopus

PubMed

researchmap

Publishing type：Research paper (scientific journal)  

© 2018 The Japanese Society for Horticultural Science (JSHS), All rights reserved. ‘Rainbow Red’ kiwifruit have been reported to gradually ripen during low temperature storage and on the vine in the absence of detectable ethylene. This study was conducted to compare the expression of ripening-related genes during storage at different temperatures and on the vine. Fruit at 5°C and 10°C ripened faster to eating quality within four weeks accompanied with increased expression of ripening-related genes: AcACO3, AcXET2, AcEXP1, AcPG, AcPMEi, AcSUS, AcβAMY1, AcβAMY2, AcGA2ox2, AcNAC3, AcNAC4, and AcMADS2. Fruit at 15°C required a longer period of eight weeks to attain eating quality in concurrence with delayed accumulation of the ripening-related genes. Fruit at 22°C ripened at the slowest rate and did not attain eating quality even after eight weeks, with very minimal accumulation of ripening-related genes. On-vine ripening occurred slowly at the early stages when the average field temperature was ~20°C, but the rate increased as the temperature dropped to ≤15°C accompanied by increased expression of ripening-related genes. These results indicate that both ripening on-vine and during low temperature storage are modulated by low temperature independent of ethylene.

DOI： 10.2503/hortj.OKD-035

Web of Science

Scopus

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society for Horticultural Science  

Split-pit in peach fruit is a problematic disorder. Split-pit fruit cannot be detected based on external appearance, and contamination of fruit by split-pit reduces its reliability in the marketplace. Here, we demonstrate that split-pit fruit can be identified by a nondestructive acoustic vibration method and a unique approach based on the ratio of the third (f3) to the second (f2) resonant frequency. The response-resonant frequency spectra showed that the peaks of f2 frequencies in split-pit fruit were shifted to much lower values than those in normal fruit, whereas those of f3 frequencies showed only small shifts. The calculated f3/f2 ratios in most normal fruit were in the range of 1.35–1.4, whereas those in split-pit fruit were 1.45–2.0. Analysis of more than 300 fruit samples revealed that by setting the f3/f2 cut-off value at &gt
1.45, 95% of split-pit fruit in the fruit samples were detected, whereas only 1.5% of normal fruit were missorted as split-pit fruit. A model for simulating the vibration properties of peach fruit was developed by using the finite element method. The simulated vibration patterns showed that f3/f2 values were increased by the insertion of split pit, indicating that, at least partially, the observed high f3/f2 values in split-pit fruit directly reflected split-pit occurrence. These results clearly demonstrate that the use of f3/f2 ratios obtained using an acoustic vibration method can effectively detect fruit with split-pit. The possibility of installing acoustic vibration devices in peach sorting lines and the application of portable devices to unpicked fruit on the tree are discussed.

DOI： 10.2503/hortj.OKD-094

Web of Science

Scopus

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC HORTICULTURAL SCI  

The responses of three kiwifruit cultivars, Actinidia chinensis 'Sanuki Gold', A. chinensis 'Rainbow Red', and A. deliciosa 'Hayward' to various storage temperatures (0, 5, 10, 15, and 20 degrees C) for 8 weeks were investigated. The rate of fruit which initiated ethylene production due to rot development increased with increases in storage temperature. Early-maturing cultivars, 'Rainbow Red' and 'Sanuki Gold' fruit stored at 5, 10, and 15 degrees C showed drastic softening and a decrease in titratable acidity (TA) to an edible level within 4 weeks without detectable ethylene production, whereas fruit stored at 0 and 20 degrees C maintained high firmness and TA even after 8 weeks unless they were infected with rot. A late-maturing cultivar, 'Hayward' fruit stored at 5 and 10 degrees C softened more rapidly than when stored at 0, 15, or 20 degrees C. Treatment with 1-Methylcyclopropene (1-MCP) did not suppress the low temperature modulated fruit ripening in any cultivars, indicating its independence from ethylene. These results suggest that 'Sanuki Gold' and 'Rainbow Red' are more sensitive to low temperatures compared to 'Hayward' and the sensitivity is involved in the determination of storage life and how early the fruit matures on the vine.

DOI： 10.2503/hortj.OKD-028

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

The aluminum-activated malate transporter (ALMT) family of proteins transports malate and/or inorganic anions across plant membranes. To demonstrate the possible role of ALMT genes in tomato fruit development, we focused on SlALMT4 and SlALMT5, the two major genes expressed during fruit development. Predicted proteins were classified into clade 2 of the family, many members of which localize to endomembranes. Tissue-specific gene expression was determined using transgenic tomato expressing the beta-glucuronidase reporter gene controlled by their own promoters. Both the genes were expressed in vascular bundles connecting to developing seeds in fruit and in the embryo of mature seeds. Further, SlALMT5 was expressed in embryo in developing seeds in fruit. Subcellular localization of both proteins to the endoplasmic reticulum (ER) was established by transiently expressing the green fluorescent protein fusions in plant protoplasts. SlALMT5 probably localized to other endomembranes as well. Localization of SlALMT5 to the ER was also confirmed by immunoblot analysis. The transport function of both SlALMT proteins was investigated electrophysiologically in Xenopus oocytes. SlALMT5 transported malate and inorganic anions such as nitrate and chloride, but not citrate. SlALMT4 also transported malate, but the results were less consistent perhaps because it did not localize strongly to the plasma membrane. To elucidate the physiological role of SlALMT5 further, we over-expressed SlALMT5 in tomato. Compared with the wild type, overexpressors exhibited higher malate and citrate contents in mature seeds, but not in fruit. We conclude that the malate transport function of SlALMT5 expressed in developing fruit influences the organic acid contents in mature seeds.

DOI： 10.1093/pcp/pcw157

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC HORTICULTURAL SCI  

In order to extend the "eating window", the optimum ripening phase suitable for eating, the combination of treatment with propylene (an ethylene analog) and 1-methylcyclopropene (1-MCP; an ethylene inhibitor) was assessed in three kiwifruit cultivars: 'Rainbow Red' Actinidia chinensis, 'Sanuki Gold' A. chinensis, and 'Hayward' A. deliciosa. Propylene treatment initiated the ripening process by inducing fruit softening, increasing soluble solid content (SSC), and decreasing titratable acids (TA), with or without endogenous ethylene production, depending on the duration of exposure. Once endogenous ethylene was induced, it accelerated fruit ripening, resulting in an over-ripening phase and shortening of the "eating window". 'Rainbow Red' and 'Sanuki Gold' fruit treated with propylene continuously or for 48 h initiated endogenous ethylene production that led to an "eating window" lasting only 2 days (range of 3-5 days after the start of treatment), whereas it lasted for 7 days (range 3-10 days) in 'Hayward' fruit. Limited propylene treatment of the three cultivars for 24 h induced ripening without the detection of ethylene production, suggesting that the optimum ripening phase suitable for eating can be attained without endogenous ethylene production, resulting in a longer "eating window". 'Rainbow Red' and 'Sanuki Gold' fruit treated with propylene for 48 h followed by 1-MCP treatment had extended "eating window" and shelf-life, with the suppression of endogenous ethylene. These results illustrate the practicability of different durations of propylene treatment in facilitating kiwifruit ripening and the additional benefit of 1-MCP treatment to the extend shelf-life of new high-quality kiwifruit cultivars, 'Rainbow Red' and 'Sanuki Gold'.

DOI： 10.2503/hortj.MI-066

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We investigated the physiological effects of short-term postharvest near infrared (NIR) radiation on relative transpiration rates, stomatal apertures, and reactive oxygen species (ROS) levels in guard cells on excised young lettuce leaves and on transpiration of leaf lettuce at commercial maturity. When the young leaves were radiated by NIR of wavelengths longer than 850 nm at 100 mu mol m(-2) s(-1) for short duration (10-60) min, relative transpiration rates during subsequent storage were reduced, but not by visible light radiation and by longer radiation (180 min) of NIR. The reduction in transpiration rates by the short-term NIR radiation was greater at 10 degrees C than at 25 degrees C under both dark and light conditions during subsequent storage. The short-term NIR radiation enhanced stomatal closure and ROS accumulation in guard cells of young lettuce leaves. These results indicate that the suppression of transpiration by short-term NIR radiation is likely to be mediated through stomatal closure due to NIR-induced ROS accumulation. The reduction of transpiration by short-term NIR radiation was obtained not only in excised young leaves but also in leaf lettuce at commercial maturity, resulting in keeping freshness. The short-term NIR radiation could be an additional means to extend shelf life of leaf vegetables. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.postharvbio.2015.05.010

Web of Science

researchmap

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC HORTICULTURAL SCI  

Two types of floral morph, called thrum and pin, occur in heterostylous species. The thrum and pin flowers have shorter and longer styles, respectively. Heterostyly in Linum has been studied since Darwin's era. The floral morph, self-incompatibility, and related phenotypes have been well characterized using a natural population, but genetic analysis using a segregated population has not been reported, and the mode of inheritance of heterostyly in Linum remains to be investigated. We prepared a segregated population by crossing thrum and pin flowers of Linum grandiflorum Desf. and investigated style and stamen lengths. On the basis of the style to stamen length ratio, the population could be divided into thrum and pin clearly at a ratio of 1:1. Style length of pins was 1.6 times longer than that of thrums. To investigate the factor regulating the difference in style length, we further measured the style cell length of thrums and pins. The style cell length of pins was longer than that of thrums, whose rate was comparable to the rate of the style length ratio between thrum and pin flowers. These findings indicate that the floral morph of heterostyly in Linum is controlled by a single diallelic locus, and that a difference in the cell expansion rate caused thrum and pin morphs in the style, such as in a typical heterostylous species. PCR genotyping showed that TSS1, an S candidate gene reported previously, cosegregated completely with the thrum phenotype, indicating strong linkage between the S locus and TSS1. Furthermore, three flower colors (red, pink, and white) were observed at a 1:2:1 ratio, and no white thrum flowers or red pin flowers were found in this population. These flower color phenotypes could also be controlled by a diallelic locus, whose two alleles (R and r) would be incompletely dominant, and therefore, may be linked to the S locus.

DOI： 10.2503/hortj.MI-045

Web of Science

researchmap

Publishing type：Research paper (scientific journal)   Publisher：Japanese Society for Horticultural Science  

DOI： 10.2503/hrj.14.61

researchmap

Language：Japanese   Publisher：THE JAPANESE SOCIETY FOR HORTICULTURAL SCIENCE  

As green soybeans, immature seeds of Glycine max (L.) Merr., are usually harvested during summer, their quality rapidly deteriorates after harvest. We determined several quality attributes of postharvest green soybeans stored at various temperatures with short intervals and the effects of configuration (with or without leaves and stems) in 'Hukura' and 'Yuagari-musume'. In both cultivars, green soybeans stored at 15°C or higher showed a 20% or greater decrease in total sugars and free amino acids only 3 h and 6 h after harvest respectively, compared with levels at harvest. Storage temperatures at 10°C or lower were effective in preserving the appearance of pods and resulted in an 80% or greater retention of the level at harvest of total sugars and free amino acids even after 10 h and 24 h storage, respectively. Storing green soybeans with leaves and stems at room temperature had a slightly beneficial effect on the retention of quality attributes; however, the effects of the storage temperature were much more marked than those of the configuration. These results indicate that cooling at 10°C or lower within 3 h after harvest is important for the quality control of green soybeans.

DOI： 10.2503/hrj.14.297

CiNii Article

CiNii Books

researchmap

Other Link： http://agriknowledge.affrc.go.jp/RN/2010892824

Language：Japanese   Publisher：Japan Society for Food Engineering  

Effects of ratio of first and second cooking periods before and after freeze on physical characteristics in green soybeans were determined to study effects of gelatinization level before freezing, in the condition that total cooking period was set at 210 seconds. The green soybeans gelatinized to 55-83% by first cooking exhibited higher firmness and higher crispness index (CI) after both they were thawed and fully gelatinized by second cooking, compared with other gelatinization degree at first cooking. The firmness and CI of green beans frozen with gelatinization level less than 41% were relatively high after thawing but decreased severely after second cooking. The green beans gelatinized over 92% by first cooking had considerably low CI after thawing. SEM imaging confirmed that cell structure of green soybeans gelatinized to 55-83% by first cooking was more intact even after they were thawed and fully then gelatinized than that of soybeans cooked with other condition.

DOI： 10.11301/jsfe.16.63

CiNii Article

CiNii Books

researchmap

Other Link： http://agriknowledge.affrc.go.jp/RN/2010891565

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Double flowers induced by virus-induced gene silencing (VIGS) of two C-class MADS-box genes, pMADS3 and FBP6, were investigated in four cultivars of Petunia hybrida. In flowers induced by either pMADS3-VIGS or FBP6-VIGS, only small changes in commercial appearance were recognized regardless of cultivar, whereas in those induced by pMADS3/FBP6-VIGS, complete conversion of stamens into petaloid tissues and marked enlargement of upper limb-like tissues were observed, resulting in a decorative appearance in all the four cultivars. In whorl 4, cultivar-dependent conversion of carpels into new flowers was noted in pMADS3/FBP6-VIGS flowers. Of the four cultivars, only 'Mambo Purple' exhibited the development of new flowers instead of carpels and the emergence of ectopic new flowers from the axil of whorl 3 organs, which created an ornamental appearance with a high commercial value. Investigation of large and small petaloid stamens induced by pMADS3/FBP6-VIGS and pMADS3-VIGS, respectively, revealed only small differences in cell size compared to the large difference in total surface area. Quantitative RT-PCR analysis of SQUAMOSA/AP1/FRU type A-class genes, FBP29, PFG, and FBP26, showed no close relationship between the expression of those genes and petaloid stamen size. The suppressed C-class gene function at the late stage of flower development has little influence on the final size of petaloid tissue. (C) 2014 Elsevier IV. All rights reserved.

DOI： 10.1016/j.scienta.2014.07.029

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Heterostylous species have two types of flowers, thrum and pin morphs, and these are controlled by a single diallelic locus designated the S locus; fertilization between these two types of flowers is successful. The S gene and the molecular mechanism by which it operates remain to be uncovered, although heterostyly has been studied since the time of Darwin. We compared transcripts and proteins of the thrum and pin flowers of heterostylous flax (Linum grandiflorum) to characterize the molecular differences between them and to elucidate the molecular machinery of heterostyly. Twelve floral morph-related genes were eventually isolated by an integrated study of subtraction and 2D-PAGE analyses, and four genes, TSS1, LgAP1, LgMYB21 and LgSKS1, were predicted to be related to heterostyly. TSS1, a thrum style-specific gene, showed some features suitable for the S gene. Although its biological function is unclear, TSS1 was expressed only in the thrum style and is probably linked to the S locus. LgMYB21, another thrum style gene, would be involved in floral morphogenesis. LgMYB21 was highly expressed in the thrum style, which is shorter than the pin style, and its overexpression in Arabidopsis reduced pistil length. Furthermore, a comparison of transcript and protein accumulations showed no differences in the mRNA accumulation of some thrum-specific proteins, including LgSKS1, suggesting that these are regulated by floral morph-specific post-transcriptional regulation. The Linum S locus regulates not only S specificity but also many floral phenotypes. Dynamic regulation of transcripts and proteins would be necessary for the pleiotropic function of the Linum S locus.

DOI： 10.1111/j.1365-313X.2011.04792.x

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

Fruit ripening in response to treatments with propylene, 1-methycyclopropene (1-MCP), and low temperature was characterized in 'Sanuki Gold' kiwifruit, Actinidia chinensis Planch. Propylene treatment immediately induced rapid fruit softening, increased AC-PG (polygalacturonase) and AC-EXP (expansin) mRNA accumulation, and stimulated an increase in the soluble solid concentration (SSC) and a decrease in titratable acidity (TA). After 3 d exposure to propylene, ethylene production and AC-PL (pectate lyase) mRNA accumulation were observed. 1-MCP treatment after 24 h exposure to propylene eliminated AC-PG mRNA accumulation and suppressed continued changes in SSC and TA. Application of 1-MCP at the start of the treatment, followed by continuous propylene exposure, markedly delayed fruit softening, and the expression of the cell wall-modifying genes, and changes in the SSC and TA, indicating that kiwifruit become insensitive to ethylene at least for 3 d following 1-MCP exposure. Surprisingly, significant fruit softening, mRNA accumulation of AC-PG, AC-PL, and AC-EXP, and decreased TA were observed without ethylene production in intact fruit stored at low temperature for 1 month, but not in fruit stored at room temperature. Repeated 1-MCP treatments (twice a week) failed to inhibit the changes that occurred in low temperature storage. These observations indicate that low temperature modulates the ripening of kiwifruit in an ethylene-independent manner, suggesting that kiwifruit ripening is inducible by either ethylene or low temperature signals.

DOI： 10.1093/jxb/err324

Web of Science

researchmap

Language：English   Publisher：AMER SOC PLANT BIOLOGISTS  

DOI： 10.1105/tpc.111.231260

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

The S-RNase-based gametophytic self-incompatibility (SI) of Rosaceae, Solanaceae, and Plantaginaceae is controlled by at least two tightly linked genes located at the complex S locus; the highly polymorphic S-RNase for pistil specificity and the F-box gene (SFB/SLF) for pollen. Self-incompatibility in Prunus (Rosaceae) is considered to represent a self recognition by a single factor system, because loss-of-function of SFB is associated with self-compatibility, and allelic divergence of SFB is high and comparable to that of S-RNase. In contrast, Petunia (Solanaceae) exhibits non-self recognition by multiple factors. However, the distribution of self recognition and non-self recognition SI systems in different taxa is not clear. In addition, in non-self recognition systems, a loss-of-function phenotype of pollen S is unknown. Here we analyze the divergence of SFBB genes, the multiple pollen S candidates, of a rosaceous plant Japanese pear (Pyrus pyrifolia) and show that intrahaplotypic divergence is high and comparable to the allelic diversity of S-RNase while interhaplotypic divergence is very low. Next, we analyzed loss-of-function of the SFBB1 type gene. Genetic analysis showed that pollen with the mutant haplotype S4sm lacking SFBB1-S4 is rejected by pistils with an otherwise compatible S1 while it is accepted by other non-self pistils. We found that the S5 haplotype encodes a truncated SFBB1 protein, even though S5 pollen is accepted normally by pistils with S1 and other non-self haplotypes. These findings suggest that Japanese pear has a non-self recognition by multiple factors SI system, although it is a species of Rosaceae to which Prunus also belongs.

DOI： 10.1111/j.1365-313X.2011.04752.x

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC HORTICULTURAL SCI  

The effects of modified atmosphere (MA) storage and application of 1-methylcyclopropene (1-MCP) at harvest on the storability and quality of 'Sanuki Gold' kiwifruit harvested at two different maturity stages were investigated. MA storage in both fruit harvested early at 136 days after pollination (DAP) or late at 154 DAP delayed flesh softening, increase in soluble solid concentrations (SSC), decrease in titratable acids (TA), and reduction in fruit flesh color index compared to air stored fruit, suggesting that MA storage is effective in prolonging 'Sanuki Gold' kiwifruit storage life. Further, MA stored fruit did not attain full ripening flesh firmness and SSC thresholds even after 4 months of storage under MA conditions, suggesting that early harvested 'Sanuki Gold' kiwifruit can be stored for 4 months in MA. Fruit from both harvesting maturity stages stored under air conditions achieved maximum SSC (18%) values during storage, suggesting that two weeks early harvesting did not compromise edible quality characteristics. Only late harvested fruit treated with 1-MCP and stored in MA showed slight inhibitory effect specific to fruit softening during the first and second month of storage, suggesting that 1-MCP may have some limited ripening inhibitory effect during storage of 'Sanuki Gold' kiwifruit.

DOI： 10.2503/jjshs1.80.372

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Ethylene biosynthesis in kiwiftuit, Actinidia chinensis &apos;Sanuki Gold&apos; was characterized using propylene, an ethylene analog, and 1-methylcyclopropene (1-MCP), an inhibitor of ethylene perception. In fruit harvested between a young stage (66 days after pollination) (DAP) and an early commercial harvesting stage (143 DAP), 2 days of exposure to propylene were sufficient to initiate ethylene biosynthesis while in fruit harvested at commercial harvesting stage (154 DAP), 4 days of propylene treatment were required. This observation suggests that response of ethylene biosynthesis to propylene treatment in kiwifruit declined with fruit maturity. Propylene treatment resulted in up-regulated expression of AC-ACO1, AC-ACO2, AC-SAM1 and AC-SAM2, prior to the induction of AC-ACS1 and ethylene production, confirming that AC-ACS1 is the rate limiting step in ethylene biosynthesis in kiwiftuit. Treatment of fruit with more than 5 mu L L(-1) of 1-MCP after the induction of ethylene production subsequently suppressed ethylene production and expression of ethylene biosynthesis genes. Treatment of fruit with 1-MCP at harvest followed with propylene treatment delayed the induction of ethylene production and AC-ACS1 expression for 5 days. These observations suggest that in ripening kiwifruit, ethylene biosynthesis is regulated by positive feedback mechanism and that 1-MCP treatment at harvest effectively delays ethylene production by 5 days. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.postharvbio.2009.08.007

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

Gametophytic self-incompatibility (GSI) in Solanaceae, Rosaceae, and Plantaginaceae is controlled by a multiallelic S-locus. The specificities of pistil and pollen are controlled by separate S-locus genes, S-RNase and SLF/SFB, respectively. Although the S-specificity is determined by the S-locus genes, factors located outside the S-locus are also required for expression of GSI. HT-B is one of the pistil non-S-factors identified in Nicotiana and Solanum, and encodes a small asparagine/aspartate-rich extracellular protein with unknown biochemical function. Here, HT-B was cloned from Petunia and characterized. The structural features and expression pattern of Petunia HT-B were very similar to those of Nicotiana and Solanum. Unlike other solanaceous species, expression of HT-B was also observed in self-compatible Petunia species. RNA interference (RNAi)-mediated suppression of Petunia HT-B resulted in partial breakdown of GSI. Quantitative analysis of the HT-B mRNA accumulation in the transgenics showed that a 100-fold reduction is not sufficient and a &gt; 1000-fold reduction is required to achieve partial breakdown of GSI.

DOI： 10.1093/jxb/erp005

Web of Science

researchmap

Language：Japanese   Publisher：日本食品保蔵科学会  

&#039;La France&#039; European pear fruit undergoes dramatic softening during ripening in an ethylene-dependent manner, whereas &#039;Yali&#039; Chinese pear does not exhibit softening in spite of its massive ethylene production during ripening. To identify the key factors involved in fruit softening, the two-dimensional gel electrophoresis profiles of cell wall proteins extracted from ripening flesh tissues of &#039;La France&#039; and &#039;Yali&#039; pears were compared. The accumulation levels of 19 protein spots changed significantly during the ripening in &#039;La France&#039; pear. When softening pears of this variety were treated with 1-MCP, a strong ethylene inhibitor, fruit softening was retarded. In parallel with this retardation, the levels of 15 of the 19 protein spots were restored or decreased to those at preclimacteric stages. For &#039;Yali&#039; pear, the accumulation levels of 8 of the 15 protein spots remained unchanged during ripening, suggesting the involvement of these 8 proteins in the nonsoftening feature of &#039;Yali&#039; pear. We therefore selected 2 of the 8 protein spots as potential key factors of fruit softening, since their accumulation was up-regulated during the ripening in &#039;La France&#039; pear.

DOI： 10.5891/jafps.34.127

CiNii Article

CiNii Books

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We investigated the differences in capability to produce ripening-associated ethylene between climacteric ('Yali', 'Xinqingli', and 'Zhuzuili') and non-climacteric ('Hongli', 'Yuanbali', and 'Hongxiaoli') Chinese pear (Pyrus bretschneideri Rehder) fruit varieties. Three ACS (PbACS1, PbACS2, and PbACS3), two ACO (PbACO1 and PbACO2), and three MADS-box (PbMADS1, PbMADS2, and PbMADS3) genes were cloned from ripening fruit. Fruit were harvested at the mature stage and treated with 5000 mu L L-1 propylene for 4 days. Ethylene production was induced by propylene in the climacteric but not in non-climacteric type fruit. In the ripening climacteric fruit, PbACS1 and PbACO1 transcript accumulation accompanied ethylene production but the accumulation of other ACS and ACO mRNAs was not detected. In 'Yali' fruit, 1-MCP exposure prior to propylene treatment completely inhibited the expression of these genes, while exposure after the commencement of ethylene production weakened their expression. Transcripts of PbACO1 accumulated in response to propylene treatment even in non-climacteric fruit but this accumulation was eliminated after the termination of propylene treatment. In response to wounding, transcripts of PbACS2, PbACS3, and PbACO2 genes accumulated in both climacteric and non-climacteric fruit, but accumulation of PbACS1 and PbACO1 mRNAs was not detected. In the Southern analysis of PbACS1, HindIII digests of genomic DNA showed 8.3, 3.5 and 2.9 kb bands. The 2.9 kb band was detected only in climacteric varieties while the 3.5 kb band was detected in both climacteric and non-climacteric varieties except in 'Yali'. These results suggest that Chinese pears may have two copies of the ACSI gene, in which PbACS1A could be linked to the varietal differences in the capability to produce ripening-associated ethylene. There was no correlation between the expression patterns of the three MADS-box genes cloned and the differences in ripening-associated ethylene production among the Chinese pear varieties. (C) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.postharvbio.2006.12.010

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：GENETICS  

Although recent findings suggest that the F-box genes SFB/SLF control pollen-part S specificity in the S-RNase-based gametophytic self-incompatibility (GSI) system, how these genes operate in the system is unknown, and functional variation of pollen S genes in different species has been reported. Here, we analyzed the S locus of two species of Maloideae: apple (Malus domestica) and Japanese pear (Pyrus pyrifolia). The sequencing of a 317-kb region of the apple S-9 haplotype revealed two similar F-box genes. Homologous sequences were isolated from different haplotypies of apple and Japanese pear, and they were found to be polymorphic genes derived from the Slocus. Since each S haplotype contains two or three related genes, the genes were named SFBB for S locus F-box brothers. The SFBB genes are specifically expressed in pollen, and variable regions of the SFBB genes are under positive selection. In a style-specific mutant S haplotype of Japanese pear, the SFBB genes are retained. Apart from their multiplicity, SFBB genes meet the expected characteristics of pollen S. The unique multiplicity of SFBB genes as the pollen S candidate is discussed in the context of mechanistic variation in the S-RNase-based GSI system.

DOI： 10.1534/genetics.106.068858

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC HORTICULTURAL SCI  

Substantial decreases in cell wall bound galactosyl and arabinosyl residues are two of the most evident cell wall compositional changes that occur during fruit ripening. The roles of P-galactosidase (P-Gal) and alpha-L-arabinofuranosidase (alpha-Af), the enzymes responsible for these respective losses, were investigated and compared in European (Pyrus communis L. 'La France') and Chinese (Pyrus bretschneideri Rehd. 'Yali') pear fruits which exhibit different softening characteristics during ripening. The increase in the activities of P-Gal and a-Af during ripening in both types of pear fruit correlated well with an increase in climacteric ethylene production, and a concomitant decrease in flesh firmness in 'La France' fruit. However, there was no noticeable decrease in 'Yali' flesh firmness even after 28 days of storage at room temperature. In both fruit types, enzyme activity and the accumulation of transcripts hybridizing with PpGAL1, PpGAL4, PpARF2, and PcARF1 increased with fruit ripening. Increases in gene expression and enzyme activities in 'Yali' fruit with no detectable softening during ripening indicate that P-Gal and a-Af may not mediate difference in fruit softening between two pears, but that they could play some role(s) in cell wall changes, perhaps in cooperation with other cell wall-modifying enzymes such as polygalacturonase.

DOI： 10.2503/jjshs.76.85

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

Cell wall disassembly in ripening fruit is highly complex, involving the dismantling of multiple polysaccharide networks by diverse families of wall-modifying proteins. While it has been reported in several species that multiple members of each such family are expressed in the same fruit tissue, it is not clear whether this reflects functional redundancy, with protein isozymes from a single enzyme class performing similar roles and contributing equally to wall degradation, or whether they have discrete functions, with some isoforms playing a predominant role. Experiments reported here sought to distinguish between cell wall-related processes in ripening melon that were softening-associated and softening-independent. Cell wall polysaccharide depolymerization and the expression of wall metabolism-related genes were examined in transgenic melon (Cucumis melo var. cantalupensis Naud.) fruit with suppressed expression of the 1-aminocyclopropane-1-carboxylate oxidase (ACO) gene and fruits treated with ethylene and 1-methylcyclopropene (1-MCP). Softening was completely inhibited in the transgenic fruit but was restored by treatment with exogenous ethylene. Moreover, post-harvest application of 1-MCP after the onset of ripening completely halted subsequent softening, suggesting that melon fruit softening is ethylene-dependent. Size exclusion chromatography of cell wall polysaccharides, from the transgenic fruits, with or without exogenous ethylene, indicated that the depolymerization of both pectins and xyloglucans was also ethylene dependent. However, northern analyses of a diverse range of cell wall-related genes, including those for polygalacturonases, xyloglucan endotransglucosylase/hydrolases, expansin, and beta-galactosidases, identified specific genes within single families that could be categorized as ethylene-dependent, ethylene-independent, or partially ethylene-dependent. These results support the hypothesis that while individual cell wall-modifying proteins from each family contribute to cell wall disassembly that accompanies fruit softening, other closely related family members are regulated in an ethylene-independent manner and apparently do not directly participate in fruit softening.

DOI： 10.1093/jxb/erl283

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

We investigated the role of beta-galactosidase (EC 3.2.1.23; beta-Gal) in 'La France' pear (Pyrus communis L.) fruit growth and softening at both biochemical and molecular levels. Northern hybridization was carried out using probes prepared from Japanese pear beta-galactosidase (PpGAL) cDNA clones, designated PpGAL1, PpGAL2, PpGAL3, PpGAL4, PpGAL5, PpGAL6 and PpGAL7. P-Galactosidase activity and accumulation of the transcripts hybridizing with the PpGAL genes were investigated during fruit growth and in relation to fruit softening and in response to propylene and 1-methylcyclopropene (1-MCP) treatments during postharvest ripening. beta-Galactosidase activity was highest in very young fruit, decreased to low levels in later stages of fruit expansion and then increased during postharvest ripening. The increase in beta-Gal activity during fruit ripening paralleled the decrease in fruit firmness. Transcripts hybridizing with PpGAL1 and PpGAL4 were not detected during fruit growth but were detected in the ripening fruit. On the contrary, the abundance of transcripts hybridizing with PpGAL2, PpGAL3, PpGAL5, PpGAL6 and PpGAL7 was highest in the early stages of fruit development, decreased towards fruit maturity and except for PpGAL2 were detected in the ripening fruit, albeit at low levels. Propylene treatment resulted in increased ethylene production, decreased fruit firmness and increased beta-Gal activity. Besides, propylene stimulated the accumulation of transcripts hybridizing with PpGAL1 and PpGAL4 and suppressed the accumulation of transcripts hybridizing with PpGAL6 and PpGAL7 and had no effect on transcripts hybridizing with PpGAL2, PpGAL3 and PpGAL5. The converse was true for fruit treated with 1-MCP, although the inhibition of the accumulation of transcripts hybridizing with PpGAL1 and PpGAL4 by 1-MCP was not complete. These results indicate that PpGAL1 and PpGAL4 play a crucial role in 'La France' pear fruit softening and the increase in their expression at the onset of fruit ripening is in part due to up-regulation by ethylene. The decrease in transcripts hybridizing with PpGAL6 and PpGAL7 in ripe fruit may in part be due to down-regulation by ethylene whereas that of transcripts hybridizing with PpGAL2, PpGAL3 and PpGAL5 may be due to another mechanism(s) unrelated to ethylene action. The divergent members of the P-Gal gene family in 'La France' pear fruit, therefore, have differential developmental and hormonal regulation characteristics. (c) 2005 Published by Elsevier B.V.

DOI： 10.1016/j.postharvbio.2005.02.002

Web of Science

Scopus

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Gametophytic self-incompatibility (GSI) in sweet cherry (Prunus avium, Rosaceae) is controlled by the multi-allelic S-locus. This complex locus contains two linked genes, an S-RNase that controls pistil specificity, and an F-box gene named SFB (S-haplotype-specific F-box protein gene) that is the putative determinant of pollen specificity in Prunus species. The S-locus is considered to be a region of repressed recombination, as recombination has not been observed. Recombination between the pistil-S and pollen-S determinant genes would result in non-functional S-haplotypes and loss of self-incompatibility. With the recent identification of multiple SFB alleles in sweet cherry, along with the existing S-RNase alleles, it is now possible to estimate the linkage distance and quantify the physical distance between the two GSI specificity genes in multiple sweet cherry S-haplotypes. A recombinational analysis between S-RNase and SFB was performed for four sweet cherry S-haplotypes (S-2, S-3, S-4, S-6) using F-1 progeny from reciprocal crosses between 'Emperor Francis' (S-3 S-4) and 'NY 54' (S-2 S-6). For SFB genotyping, allele-specific primer sets were designed from the sequence of the SFB coding region. The S-RNase and SFB genotypes of 511 progeny, representing the outcomes of 1,022 meioses, were determined. All four S-haplotypes individually segregated according to the expected Mendelian ratio of 1:1. The S-RNase and SFB loci were completely linked as no recombinant individuals were identified, thus maintaining the co-evolved allele specificities for the pistil and putative pollen determinant. The physical distance between S-RNase and SFB in six sweet cherry S-haplotypes (S1-S6) was determined using PCR with genomic clones as the template. The relative order and transcriptional orientation of S-RNase and SFB were conserved across the six S-haplotypes. However, the physical distance between these two genes varied widely, ranging from 380 bp to approximately 40 kb. This study represents the first large-scale recombinational analysis of the S-locus region in the Rosaceae, serving as the starting point for future comparative analyses of physical distances, linkage distances, and sequence diversity among Prunus S-haplotypes.

DOI： 10.1007/s00497-004-0240-x

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER-VERLAG  

The gene SFB encodes an F-box protein that has appropriate S-haplotype-specific variation to be the pollen determinant in the S-RNase-based gametophytic self-incompatibility (GSI) reaction in Prunus (Rosaceae). To further characterize Prunus SFB, we cloned and sequenced four additional alleles from sweet cherry (P. avium), SFB1, SFB2, SFB4, and SFB5. These four alleles showed haplotype-specific sequence diversity similar to the other nine SFB alleles that have been cloned. In an amino acid alignment of Prunus SFBs, including the four newly cloned alleles, 121 out of the 384 sites were conserved and an additional 65 sites had only conservative replacements. Amino acid identity among the SFBs ranged from 66.0% to 82.5%. Based on normed variability indices (NVI), 34 of the non-conserved sites were considered to be highly variable. Most of the variable sites were located at the C-terminal region. A window-averaged plot of NVI indicated that there were two variable and two hypervariable regions. These variable and hypervariable regions appeared to be hydrophilic or at least not strongly hydrophobic, which suggests that these regions may be exposed on the surface and function in the allele specificity of the GSI reaction. Evidence of positive selection was detected using maximum likelihood methods with sites under positive selection concentrated in the variable and hypervariable regions.

DOI： 10.1007/s00497-003-0200-x

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Japanese apricot ( Prunus mume) exhibits the S-RNase-based gametophytic self-incompatibility system as do other self-incompatible Prunus species. This report identifies the S haplotype-specific F-box protein gene ( SFB), a candidate gene for pollen- S, of Japanese apricot, which leads to the development of a molecular typing system for S-haplotype in this fruit species. Both 5'- and 3'-RACE (rapid amplification of cDNA ends) were performed with SFB gene-specific oligonucleotide primers to clone Pm-SFB(1) and Pm-SFB(7) of 'Nanko ( S(1) S(7))'. As in the case of SFB of other Prunus species, Pm-SFB(1) and Pm-SFB(7) showed a high level of S-haplotype-specific sequence polymorphism and their expression was specific to pollen. Genomic DNA-blot analyses of 11 Japanese apricot cultivars with the Pm-SFB probes under low stringency conditions yielded RFLP bands specific to the S(1)- to S(8)-haplotypes as well as a self-compatible S(f)-haplotype. A practical usage of SFB as a molecular marker for S-haplotypes and self-compatibility in Japanese apricot is discussed.

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

This study describes a novel F-box protein gene in the S-locus of sour cherry (Prunus cerasus) and sweet cherry (P. avium). The gene showed an S-haplotype-specific sequence polymorphism and the expression was specific to pollen. Genomic DNA blot analysis of eight sweet cherry cultivars with the probe for the F-box protein gene under low stringency conditions yielded RFLP bands specific to the S-haplotypes of each cultivar. We discuss the possibility of the gene for the F-box protein being a candidate for the male determinant of gametophytic self-incompatibility in PRUNUS:

PubMed

researchmap

DOI： 10.1105/tpc.009290

CiNii Article

CiNii Books

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

The genomic clone encoding the pistil-specific thaumatin/PR5-like protein (PsTL1) was isolated from Japanese pear (Pyrus serotina). Sequence analysis showed that the genomic clone contained the 5'-flanking sequence of 2.4 kb, the 3'-flanking sequence of 648 bp and the coding region interrupted by a intron of 351 bp. A sequence motif conserved in some pistil self-incompatibility gene promoters of solanaceous and brassicaceous species was located in the 5'-flanking region of the PsTL1 gene. The 2.4 kb 5'-flanking region was fused to the GUS coding sequence and transferred to tobacco. Transgenic tobacco showed GUS activity in pistil and, at low level, in anther, but not in other floral organs and leaf. Histochemical analysis localized GUS activity to stigma, transmitting tissue, anther and pollen of transgenic tobacco.

PubMed

researchmap

Publishing type：Research paper (scientific journal)  

In almond, gametophytic self-incompatibility is controlled by a single multiallelic locus (S-locus). In styles, the products of S-alleles are ribonucleases, the S-RNases. Cultivated almond in California have four predominant S-alleles (Sa, Sb, S(c), S(d)). We previously reported the cDNA cloning of three of these alleles, namely Sb, S(c) and S(d). In this paper we report the cloning and DNA sequence analysis of the Sa allele. The Sa-RNase displays approximately 55% similarity at the amino-acid level with other almond S-RNases (Sb, S(c), and S(d)) and this similarity was lower than that observed among the Sb, S(c) and S(d)-RNases. Using the cDNA sequence, a PCR-based identification system using genomic DNA was developed for each of the S-RNase alleles. Five almond cultivars with known self-incompatibility (SI) geno-types were analyzed. Common sequences among four S-alleles were used to create four primers, which, when used as sets, amplify DNA bands of unique size that corresponded to each of the four almond S-alleles; Sa (602 bp), Sb (1083 bp), S(c) (221 bp) and S(d) (343 bp). All PCR products obtained from genomic DNA isolated from the five almond cultivars were cloned and their DNA sequence obtained. The nucleotide sequence of these genomic DNA fragments matched the corresponding S-allele cDNA sequence in every case. The amplified products obtained for the Sa- and Sb-alleles were both longer than that expected for the coding region, revealing the presence of an intron of 84 bp in the Sa-allele and 556 bp in the Sb-allele. Both introns are present within the site of the hypervariable region common in S-RNases from the Rosaceae family and which may be important for S specificity. The exon portions of the genomic DNA sequences were completely consistent with the cDNA sequence of the corresponding S-allele. A useful application of these primers would be to identify the S-genotype of progeny in a breeding program, new varieties in an almond nursery, or new grower selections at the seedling stage.

DOI： 10.1007/s001220051489

Scopus

researchmap

Publishing type：Research paper (scientific journal)  

Genomic sequences of the self-incompatibility genes, the S-RNase genes, from two rosaceous species, Japanese pear and apple, were characterized. Genomic Southern blot and sequencing of a 4.5-kb genomic clone showed that the S4-RNase gene of Japanese pear is surrounded by repetitive sequences as in the case of the S-RNase genes of solanaceous species. The flanking regions of the S2- and S(f)-RNase genes of apple were also cloned and sequenced. The 5' flanking regions of the three alleles bore no similarity with those of the solanaceous S-RNase genes, although the position and sequence of the putative TATA box were conserved. The putative promoter regions of the Japanese pear S4- and apple S(f)-RNase genes shared a stretch of about 200 bp with 80% sequence identity. However, this sequence was not present in the S2-RNase gene of apple, and thus it may reflect a close relationship between the S4- and S(f)-RNase genes rather than a cis-element important in regulating gene expression. Despite the uniform pattern of expression of the rosaceous S-RNase genes, sequence motifs conserved in the 5' flanking regions of the three alleles were not found, implying that the cis-element controlling pistil specific gene expression also locates at the intragenic region or upstream of the analyzed promoter region.

DOI： 10.1016/S0378-1119(98)00105-X

Scopus

PubMed

researchmap

Publishing type：Research paper (scientific journal)  

cDNAs encoding three S-RNases of almond (Prunus dulcis), which belongs to the family Rosaceae, were cloned and sequenced. The comparison of amino acid sequences between the S-RNases of almond and those of other rosaceous species showed that the amino acid sequences of the rosaceous S-RNases are highly divergent, and intra-subfamilial similarities are higher than inter-subfamilial similarities. Twelve amino acid sequences of the rosaceous S-RNases were aligned to characterize their primary structural features. In spite of their high level of diversification, the rosaceous S-RNases were found to have five conserved regions, C1, C2, C3, C5, and RC4 which is Rosaceae-specific conserved region. Many variable sites fall into one region, named RHV. RHV is located at a similar position to that of the hypervariable region a (HVa) of the solanaceous S-RNases, and is assumed to be involved in recognizing S-specificity of pollen. On the other hand, the region corresponding to another solanaceous hypervariable region (HVb) was not variable in the rosaceous S-RNases. In the phylogenetic tree of the T2/S type RNase, the rosaceous S-RNase fall into two subfamily-specific groups (Amygdaloideae and Maloideae). The results of sequence comparisons and phylogenetic analysis imply that the present S-RNases of Rosaceae have diverged again relatively recently, after the divergence of subfamilies.

DOI： 10.1007/s004380050894

Scopus

PubMed

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：English  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：English  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：English   Publisher：Japanese Society for Horticultural Science  

Substantial decreases in cell wall bound galactosyl and arabinosyl residues are two of the most evident cell wall compositional changes that occur during fruit ripening. The roles of β-galactosidase (β-Gal) and α-L-arabinofuranosidase (α-Af), the enzymes responsible for these respective losses, were investigated and compared in European (Pyrus communis L. 'La France') and Chinese (Pyrus bretschneideri Rehd. 'Yali') pear fruits which exhibit different softening characteristics during ripening. The increase in the activities of β-Gal and α-Af during ripening in both types of pear fruit correlated well with an increase in climacteric ethylene production, and a concomitant decrease in flesh firmness in 'La France' fruit. However, there was no noticeable decrease in 'Yali' flesh firmness even after 28 days of storage at room temperature. In both fruit types, enzyme activity and the accumulation of transcripts hybridizing with PpGAL1, PpGAL4, PpARF2, and PcARF1 increased with fruit ripening. Increases in gene expression and enzyme activities in 'Yali' fruit with no detectable softening during ripening indicate that β-Gal and α-Af may not mediate difference in fruit softening between two pears, but that they could play some role(s) in cell wall changes, perhaps in cooperation with other cell wall-modifying enzymes such as polygalacturonase.

CiNii Article

CiNii Books

researchmap

Other Link： http://dl.ndl.go.jp/info:ndljp/pid/10471864

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

J-GLOBAL

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：English   Publisher：AMER SOC HORTICULTURAL SCIENCE  

S-4' is a pollen-part mutant in sweet cherry (Prunus avium L.) that is extensively used to develop self-compatible cultivars. The S-4'-haplotype is known to have a functional stylar component and a nonfunctional pollen component. The pollen component in sweet cherry necessary for the specificity of the pollen reaction is believed to be an S-haplotype specific F-box protein gene, called SFB. This study describes two molecular markers that distinguish between SFB4 and SFB4' by taking advantage of a four base pair deletion in the mutant allele. The resulting polymerase chain reaction (PCR) products can either be separated directly on a polyacrylamide gel or they can be subjected to restriction enzyme digestion and the different sized products can be visualized on an agarose gel. The latter technique utilizes restriction sites created in the PCR products from the SFB4' allele, but not the SFB4 allele. Because the primer sets created differential restriction sites, these primer sets were termed dCAPS (derived cleaved amplified polymorphism sequence) markers. These molecular assays can be used to verify self-compatibility conferred by the S-4-haplotype.

Web of Science

Scopus

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

CiNii Article

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：English  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

CiNii Article

CiNii Books

researchmap