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

INTRODUCTION: Collagen type XVIII regulates cellular activities of adjacent cells at the dermal-epidermal junction (DEJ). To investigate its possible changes during aging, we compared its mRNA levels and protein localization in skin samples from female participants aged 20-70 years old. In addition, we evaluated the beneficial effects of unripe peach extracts in a 3D skin model. METHODS: Sun-exposed or sun-protected female skin samples were compared by DNA array or by immunohistochemistry for basement membrane components. To evaluate protective effects of fresh unripe peach extract, UV-B irradiated human 3D skin models were incubated in the presence or absence of the extract, followed by measurements of mRNA levels by real-time PCR, or by immunohistochemistry. RESULTS: In aged skin samples, COL18A1 mRNA levels were lower and the protein localization exhibited less intensive signal by anti-collagen type XVIII immunostaining. As observed in the skin tissues, collagen type XVIII exists at the DEJ in the 3D skin model. Fresh unripe peach extract significantly improved mRNA levels and partially localizations of collagen type XVIII, suggesting that fresh unripe peach extract ameliorates DEJ damages caused by UV-B irradiation. CONCLUSION: Collagen type XVIII and fresh unripe peach extract can be promising protective cosmetic strategies against skin aging.

DOI： 10.1111/jocd.12841

PubMed

researchmap

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

Anatomy is the science and art of understanding the structure of the body and its components in relation to the functions of the whole-body system. Medicine is based on a deep understanding of anatomy, but quite a few introductory-level learners are overwhelmed by the sheer amount of anatomical terminology that must be understood, so they regard anatomy as a dull and dense subject. To help them learn anatomical terms in a more contextual way, we started a new open-source project, the Network of Anatomical Texts (NAnaTex), which visualizes relationships of body components by integrating text-based anatomical information using Cytoscape, a network visualization software platform. Here, we present a network of bones and muscles produced from literature descriptions. As this network is primarily text-based and does not require any programming knowledge, it is easy to implement new functions or provide extra information by making changes to the original text files. To facilitate collaborations, we deposited the source code files for the network into the GitHub repository (https://github.com/ryusukemomota/nanatex) so that anybody can participate in the evolution of the network and use it for their own non-profit purposes. This project should help not only introductory-level learners but also professional medical practitioners, who could use it as a quick reference.

DOI： 10.1007/s12565-017-0410-1

Scopus

PubMed

researchmap

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

Keratinized mucosa is of fundamental importance to maintain healthy gingival tissue, and understanding the mechanisms of oral mucosa keratinization is crucial to successfully manage healthy gingiva. Previous studies have shown a strong involvement of the basement membrane in the proliferation and differentiation of epithelial cells. Therefore, first, to identify the keratinized mucosa-specific basement membrane components, immunohistochemical analysis for the six alpha chains of type IV collagen was performed in 8-week-old mice. No difference in the expression pattern of type IV collagen α1(IV) and α2(IV) chains was observed in the keratinized and non-keratinized mucosa. Interestingly, however, type IV collagen α5(IV) and α6(IV) chains specifically were strongly detected in the keratinized mucosa. To analyze the functional roles of the type IV collagen isoform α6(IV) in oral mucosa keratinization, we analyzed Col4a6-knockout mice. Epithelial developmental delay and low levels of KRT10 were observed in new-born Col4a6-knockout mice. Additionally, in vitro experiments with loss-of function analysis using human gingival epithelial cells confirmed the important role of α6(IV) chain in epithelial keratinization. These findings indicate that α112:α556 (IV) network, which is the only network that includes the α6(IV) chain, is one regulator of KRT10 expression in keratinization of oral mucosal epithelium.

DOI： 10.1038/s41598-018-21000-0

Scopus

PubMed

researchmap

Language：English   Publisher：FEDERATION AMER SOC EXP BIOL  

Web of Science

researchmap

Language：Japanese   Publisher：日本結合組織学会・マトリックス研究会  

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Vertebrate collagen types XV and XVIII are broadly distributed basement membrane components, classified into a structurally distinct subgroup called "multiplexin collagens". Mutations in mammalian multiplexins are identified in some degenerative diseases such as Knobloch syndrome 1 (KNO1) or skeletal/cardiac myopathies, however, these progressive properties have not been elucidated. Here we investigated Drosophila mutants of Multiplexin (Mp), the only orthologue of vertebrate collagen types XV and XVIII, to understand the pathogenesis of multiplexin-related diseases. The mp mutants exhibited morphological changes in cardiomyocytes and progressive dysfunction of the skeletal muscles, reminiscent phenotypes observed in Col15a1-null mice. Ultrastructural analysis revealed morphologically altered mitochondria in mutants' indirect flight muscles (IFMs), resulting in severely attenuated ATP production and enhanced reactive oxygen species (ROS) production. In addition, mutants' IFMs exhibited diminished PPS integrin clustering and abolished focal adhesion kinase (FAK) phosphorylation. Furthermore, mutants' defective IFMs are improved by the administrations of cyclosporin A, an inhibitor against mitochondrial permeability transition pore (mPTP) opening or losartan, an angiotensin II type 1 receptor (AT1R) blocker. Thus, our results suggest that Mp modulates mPTP opening and AT1R activity through its binding to integrin and that lack of Mp causes unregulated mPTP opening and AT1R activity, leading to mitochondrial dysfunctions. Hence, our results provide new insights towards the roles of multiplexin collagens in mitochondrial homeostasis and may serve as pharmacological evidences for the potential use of cyclosporin A or losartan for the therapeutic strategies. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biocel.2013.02.001

Web of Science

PubMed

researchmap

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

Most blood vessels contain elastin that provides the vessels with the resilience and flexibility necessary to control hemodynamics. Pathophysiological hemodynamic changes affect the remodeling of elastic components, but little is known about their structural properties. The present study was designed to elucidate, in detail, the three-dimensional (3D) architecture of delicate elastic fibers in small vessels, and to reveal their architectural pattern in a rat model. The fine vascular elastic components were observed by a newly developed scanning electron microscopy technique using a formic acid digestion with vascular casts. This method successfully visualized the 3D architecture of elastic fibers in small blood vessels, even arterioles and venules. The subendothelial elastic fibers in such small vessels assemble into a sheet of meshwork running longitudinally, while larger vessels have a higher density of mesh and thicker mesh fibers. The quantitative analysis revealed that arterioles had a wider range of mesh density than venules
the ratio of density to vessel size was higher than that in venules. The new method was useful for evaluating the subendothelial elastic fibers of small vessels and for demonstrating differences in the architecture of different types of vessels. © Microscopy Society of America 2013.

DOI： 10.1017/S1431927612014341

Scopus

PubMed

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：HINDAWI PUBLISHING CORPORATION  

Type 2 diabetes mellitus is linked to impaired skeletal muscle glucose uptake and storage. This study aimed to investigate the fiber type distributions and the three-dimensional (3D) architecture of the capillary network in the skeletal muscles of type 2 diabetic rats. Muscle fiber type transformation, succinate dehydrogenase (SDH) activity, capillary density, and 3D architecture of the capillary network in the soleus muscle were determined in 36-week-old Goto-Kakizaki (GK) rats as an animal model of nonobese type 2 diabetes and age-matched Wistar (Cont) rats. Although the soleus muscle of Cont rats comprised both type I and type IIA fibers, the soleus muscle of GK rats had only type I fibers. In addition, total SDH activity in the soleus muscle of GK rats was significantly lower than that in Cont rats because GK rats had no high-SDH activity type IIA fiber in the soleus muscle. Furthermore, the capillary diameter, capillary tortuosity, and microvessel volume in GK rats were significantly lower than those in Cont rats. These results indicate that non-obese diabetic GK rats have muscle fiber type transformation, low SDH activity, and reduced skeletal muscle capillary content, which may be related to the impaired glucose metabolism characteristic of type 2 diabetes.

DOI： 10.1100/2012/680189

Web of Science

PubMed

researchmap

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

Multiplexin (Mp) is the Drosophila orthologue of vertebrate collagens XV and XVIII. Like them, Mp is widely distributed in the basement membranes of the developing embryos, including those of neuroblasts in the central and peripheral nervous systems, visceral muscles of the gut, and contractile cardioblasts. Here we report the identification of mutant larvae bearing piguBac transposon insertions that exhibit decrease Mp production associated with abdominal cuticular and wing margin defects, malformation of sensory organs and impaired sensitivity to physical stimuli. Additional findings include the abnormal ultrastructure of fatbody associated with abnormal collagen IV deposition, and reduced Wingless deposition. Collectively, these findings are consistent with the notion that Mp is required for the proper formation and/or maintenance of basement membrane, and that Mp may be involved in establishing the Wingless signaling gradients in the Drosophila embryo. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matbio.2011.03.008

Web of Science

PubMed

researchmap

Language：Japanese   Publisher：日本結合組織学会・マトリックス研究会  

researchmap

Language：Japanese   Publisher：日本結合組織学会・マトリックス研究会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

The skeletal muscle is classified into 2 types, slow oxidative or fast glycolytic muscle. For further characterization, we investigated the capillary architecture in slow and fast muscles. The rat soleus and extensor digitorum longus (EDL) muscles were used as representatives of slow and fast muscles, respectively. To investigate capillary density, sections of both types of muscle were stained with alkaline phosphatase; the soleus muscle showed more intense reactivity, indicating that it had a denser capillary structure than the EDL muscle. We then injected fluorescent contrast medium into samples of both muscle types for light and confocal-laser microscopic evaluation. The capillary density and capillary-to-fiber ratio were significantly higher, and the course of the capillaries was more tortuous, in the soleus muscle than in the EDL muscle. Capillary coursed more tortuously in the soleus than in the EDL muscle. Succinate dehydrogenase (SDH) activity, an indicator of mitochondrial oxidative capacity, and vascular endothelial growth factor (VEGF) expression were also significantly higher in the soleus muscle. Thus, we conclude that slow oxidative muscle possess a rich capillary structure to provide demanded oxygen, and VEGF might be involved in the formation and/or maintenance of this highly capillarized architecture.

DOI： 10.18926/AMO/32859

Web of Science

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

The skeletal muscle is classified into 2 types, slow oxidative or fast glycolytic muscle. For further characterization, we investigated the capillary architecture in slow and fast muscles. The rat soleus and extensor digitorum longus (EDL) muscles were used as representatives of slow and fast muscles, respectively. To investigate capillary density, sections of both types of muscle were stained with alkaline phosphatase; the soleus muscle showed more intense reactivity, indicating that it had a denser capillary structure than the EDL muscle. We then injected fluorescent contrast medium into samples of both muscle types for light and confocal-laser microscopic evaluation. The capillary density and capillary-to-fiber ratio were significantly higher, and the course of the capillaries was more tortuous, in the soleus muscle than in the EDL muscle. Capillary coursed more tortuously in the soleus than in the EDL muscle. Succinate dehydrogenase (SDH) activity, an indicator of mitochondrial oxidative capacity, and vascular endothelial growth factor (VEGF) expression were also significantly higher in the soleus muscle. Thus, we conclude that slow oxidative muscle possess a rich capillary structure to provide demanded oxygen, and VEGF might be involved in the formation and/or maintenance of this highly capillarized architecture.

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：INT SOC HISTOLOGY & CYTOLOGY  

A disintegrin and metalloproteinase with thrombospondin motifs 9 (ADAMTS9) is known to influence aggrecan degradation in endochondral ossification, but its role has not been well understood. In the present study, in vitro gene expression of ADAMTS9 was investigated by RT-PCR in ATDC5 cells in which experimentally chondrogenic differentiation had been induced. We also investigated the protein localization and gene expression pattern of ADAMTS9 in the tibia growth plate cartilage of male mice in a day 1 neonate, 7-week-old young adult, and a 12-week-old adult by immunohistochemistry and in situ hybridization and compared the results with the expression of proliferating cell nuclear antigen (PCNA) and type X collagen for the identification of proliferative and hypertrophic chondrocyte phenotypes, respectively. We found the gene expression of ADAMTS9 by ATDC5 cells as a dual mode, both before the expression of type X collagen and after hypertrophic differentiation. The immunoreactivity of ADAMTS9 was observed in chondrocytes of proliferative and hypertrophic zones in the growth plate. The population of ADAMTS9 positive cells decreased with age. The results of the present study suggest that ADAMTS9 might have a role in aggrecan cleavage around the chondrocytes to allow chondrocyte proliferation and hypertrophy.

DOI： 10.1679/aohc.72.175

Web of Science

PubMed

researchmap

Language：Japanese   Publisher：(一財)日本消化器病学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：INT SOC HISTOLOGY & CYTOLOGY  

In the present study, we have analyzed the a(IV) chain distribution in the subepithelial basement membrane (BM) of the rat pulmonary airway from the bronchi to alveoli. We have furthermore analyzed the a(IV) chain distribution in the subepithelial BM of the bronchioalveolar duct junction (BADJ) using a(IV) chain specific monoclonal antibodies. Our results show that the BM of the bronchial and bronchiolar epithelium contains [al(IV)](2) a2(IV) and [ a5(IV)](2) a6(IV) molecules and confirmed that the alveolar BM consists of [a1(IV)](2) a2(IV) and a3(IV) a4(IV) a5(IV) molecules. There are also small regions in BADJ consisting of only [ a] (IV)](2) a2(IV) molecules without a3(IV) a4(IV) a5(IV) and [ a5(IV)](2) a6(IV) molecules. Moreover, the bronchioalveolar stem cells (BASCs) -primordial cells for bronchiolar Clara cells and alveolar type II (AT2) cells- lie adjacent to such small regions. These findings suggest that [ al(IV)](2) a2(IV) may be important for the BASCs to self-renew or to self-maintain themselves and that microenvironments produced by a(IV) chains may be important for cell differentiation.

DOI： 10.1679/aohc.71.185

Web of Science

PubMed

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：INT SOC HISTOLOGY & CYTOLOGY  

We studied distribution patterns of type IV collagen a chains in the subepithelial basement membrane (SBM) of the human gastrointestinal tract - the esophagus through the anal canal - by immunofluorescent microscopy using alpha(IV) chain-specific monoclonal antibodies. The alpha 1(IV), alpha 2(IV), alpha 5(IV), and alpha 6(IV) chains were found in the SBM throughout the tract, indicating the localization of [alpha 1(IV)](2) alpha 2(IV) and [alpha 5(IV)](2) alpha 6(IV) heterotrimeric molecules. The [alpha 1(IV)](2) alpha 2(IV) molecule was continuously stained, while the [alpha 5(IV)]2 alpha 6(IV) molecule was weakly stained in gastric glands and small intestinal crypts. In addition, the SBM at the luminal surface epithelium of the stomach and large intestine contained small amounts of alpha 3(IV) and alpha 4(IV) chains which combined to form the alpha 3(IV) alpha 4(IV) alpha 5(IV) heterotrimeric molecule with alpha 5(IV) chain. The SBM beneath the villous epithelium of the small intestine was also demonstrated to have an alpha 3(IV) chain and alpha 4(IV) chain. Considering the specific locations of the type IV collagen trimers throughout the gastrointestinal SBM, the supramolecular network containing the alpha 3(IV) alpha 4(IV) alpha 5(IV) molecule appears to function as a selective permeability barrier and/or as a protection against chemical stress from the luminal digestive enzymes.

DOI： 10.1679/aohc.70.313

Web of Science

PubMed

researchmap

Language：English   Publisher：AMER SOC HEMATOLOGY  

DOI： 10.1182/blood.V110.11.1734.1734

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：INT SOC HISTOLOGY & CYTOLOGY  

The present study aims to identify a chains of type IV collagen in the basement membrane of the mouse ovarian follicle and examine their changes during follicular development using immunofluorescence microscopy with specific monoclonal antibodies. The basement membrane of the serous mesothelium enveloping the ovary contained all a chains of type IV collagen, alpha 1(IV) through alpha 6(IV) chains. Primordial follicles showed a distinct immunoreactivity against all six a chains in their basement membranes. Immunolabeling for alpha 3(IV) and alpha 4(IV) chains was almost eliminated in the primary follicles. In basement membranes of secondary and Graafian follicles, the immunofluorescent reaction of a3(IV) and a4(IV) chains disappeared in Graafian follicles, a partial reduction in fluorescent immunostaining intensity to alpha 5(IV) and alpha 6(IV) chains was observed; only alpha 1(IV) and alpha 2(IV) chains were not degraded throughout follicular development. On atretic follicles, in addition to alpha 1(IV) and a2(IV) chains, alpha 3(IV), alpha 4(IV), alpha 5(IV) and alpha 6(IV) chains frequently persisted. A basement membrane-like matrix within the follicular granulosa cell layer, such as the focimatrix (focal intraepithelial matrix) and/or Call-Exner body, was also recognized in mouse secondary and Graafian follicles and contained alpha 1(IV), alpha 2(IV), alpha 5(IV) and alpha 6(IV) chains but not alpha 3(IV) and alpha 4(IV) chains. We expect that the decrease in alpha(IV) chains prompts follicular development and is a prerequisite condition for follicular maturation.

DOI： 10.1679/aohc.70.243

Web of Science

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：INT SOC HISTOLOGY & CYTOLOGY  

Distributions of type IV collagen a chains in the basement membrane (BM) of human skin and its appendages were analyzed by immunofluorescent microscopy using chain-specific monoclonal antibodies. The basement membrane beneath the epidermis contained [alpha 1(IV)]2 alpha 2(IV) and [ alpha 5(IV)]2 alpha 6(IV) but no alpha 3(IV) alpha 4(IV) alpha 5(IV); this held true for at the eccrine sweat glands and glandular ducts, sebaceous glands, hair follicles, and arrector muscles of hair. The secretary portion of the eccrine sweat glands was rich in [alpha 1(IV)]2 alpha 2(IV) and had less [ alpha 5(IV)]2 alpha 6(IV), while [alpha 5(IV)]2 alpha 6(IV) was abundant in the ductal portion. In the subepidermal zone, alpha 5(IV)/ alpha 6(IV) chain negative spots (1.9-15.0 mu m) were frequently observed. Triple staining samples (Mel.2, alpha 2(IV) and alpha 5(IV) chains) showed that about 50% of epidermal melanocytes colocalized with such spots. Results suggest that these alpha 5(IV)/ alpha 6(IV) chain negative spots of the subepidermal basement membrane have a particular relationship with melanocytes and are sites for certain interactions between the two.

DOI： 10.1679/aohc.70.255

Web of Science

PubMed

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：日本結合組織学会・マトリックス研究会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：English   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：INT SOC HISTOLOGY & CYTOLOGY  

The biconcave disc shape of mammalian erythrocytes has been considered to be maintained only with a membrane underlain by a membranous cytoskeleton. Our improved ion-etching/scanning electron microscopy and saponin-ethanol treatment combined with immunocytochemistry in the human red blood cell revealed the three-dimensional structure of this cytoplasmic endoskeleton apart from the classical membranous cytoskeleton. The endoskeletal meshwork images obtained by the saponin-ethanol treatment corresponded to those by the repeated ion-etching method. The actin-rich endoskeleton was divided into two layers, one superficial and the other deep. The superficial filaments were perpendicularly connected to the membranous cytoskeleton, while the deep filaments formed an irregularly directed complicated meshwork. In the transitional hillside region between the convex periphery and concave center, the endoskeletal filaments containing a neurofilament protein ran parallel to the hillside slope toward the concave center. The endoskeleton of the erythrocyte associating with the membranous cytoskeleton may serve to keep its unique biconcave disc shape deformable, pliable, and restorable against external circumstances.

DOI： 10.1679/aohc.69.329

Web of Science

researchmap

Language：English   Publisher：ELSEVIER SCIENCE BV  

DOI： 10.1016/j.matbio.2006.08.084

Web of Science

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

We attempted to prepare colloidal iron within tissues by means of microwave irradiation. Mouse tissue blocks were fixed with a mixture of paraformaldehyde and ferric chloride in a cacodylate buffer, immersed in a cacodylate buffered ferric chloride solution, and irradiated in a microwave processor. Colloidal iron was prepared within tissues or cells, and was observed in the form of electron dense fine granules (1-2 nm in diameter) by transmission electron microscopy. Collagen fibrils in the connective tissue showed colloidal iron deposition at regular periodical intervals. Cells in the splenic tissue showed that fine colloidal granules were deposited on the ribosomes but not on the nuclear chromatin. This finding suggests that ferric ions could not diffuse into the nucleus, which was surrounded by the nuclear envelope. The podocyte processes of the renal glomerulus were stained diffusedly. Though this microwave in situ colloidal iron preparation method has some limitations, it is convenient for use in biomedical specimen preparation in transmission electron microscopy.

DOI： 10.18926/AMO/30753

Web of Science

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

We attempted to prepare colloidal iron within tissues by means of microwave irradiation. Mouse tissue blocks were fixed with a mixture of paraformaldehyde and ferric chloride in a cacodylate buffer, immersed in a cacodylate buffered ferric chloride solution, and irradiated in a microwave processor. Colloidal iron was prepared within tissues or cells, and was observed in the form of electron dense fine granules (1-2 nm in diameter) by transmission electron microscopy. Collagen fibrils in the connective tissue showed colloidal iron deposition at regular periodical intervals. Cells in the splenic tissue showed that fine colloidal granules were deposited on the ribosomes but not on the nuclear chromatin. This finding suggests that ferric ions could not diffuse into the nucleus, which was surrounded by the nuclear envelope. The podocyte processes of the renal glomerulus were stained diffusedly. Though this microwave in situ colloidal iron preparation method has some limitations, it is convenient for use in biomedical specimen preparation in transmission electron microscopy.

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE BIOCHEMICAL SOC  

We first completed the primary structure of the mouse alpha 5(IV) and alpha 6(IV) chains, from which synthetic peptides were produced and alpha chain-specific monoclonal antibodies were raised. Expression of collagen IV genes in various basement membranes underlying specific organ epithelia was analyzed by immunohistochemical staining using these monoclonal antibodies and other antibodies from human and bovine sequences. It was possible to predict the presence of the three collagen TV molecules: [alpha 1(IV)](2) alpha 2(IV), alpha 3(IV)alpha 4(IV)alpha 5(IV), and [alpha 5(IV)](2)alpha 6(IV), In skin basement membrane two of the three forms, [alpha 1(IV)](2)alpha 2(IV) and [alpha 5(IV)](2)alpha 6(IV), were detected. The alpha 3(IV)alpha 4(IV)alpha 5(IV) molecule was observed as the major form in glomerulus, alveolus, and choroid plexus, where basement membranes function as filtering units. The molecular form [alpha 5(IV)](2)alpha 6(IV) was present in basement membranes in tubular organs such as the epididymis, where the tubes need to expand in diameter. Thus, the distribution of the basement membranes with different molecular composition is consistent with tissue-specific function.

Web of Science

researchmap

Language：English   Publisher：JAPANESE BIOCHEMICAL SOC  

Six distinct genes have been identified as belonging to the type IV collagen gene family. They can be organized into three sets, i.e., COL4A1/COL4A2, COL4A3/COL4A4, and COL4A5/COL4A6, which are localized on three different chromosomes in humans, 13, 2, and X, respectively, Within each set the genes are aligned head-to-head and their expression is regulated by bidirectional promoters between the genes. Transcriptional regulation of the COL4A1/COL4A2 set has been well characterized, The transcription of COL4A6 seems to be controlled by two alternative promoters. While collagen IV molecules composed of alpha 1 and alpha 2 chains are broadly distributed, molecules comprising combinations of the other four chains, alpha 3-alpha 6, are important components of specialized basement membranes, The precise chain composition of triple-helical molecules assembled from the alpha 3-alpha 6 chains is not entirely clear, but it is hypothesized that alpha 3-alpha 5 chains and alpha 5 and alpha 6 chains form heterotrimeric molecules. Several pieces of evidence indicate that alpha 3/alpha 4/alpha 5 molecules and alpha 5/alpha 6 molecules are components of the basement membrane network, This helps explain the observation that the kidney and skin basement membranes from patients with Alport syndrome caused by mutations in the alpha 5 coding gene, COL4A5, are defective in the alpha 3, alpha 4, and alpha 6 chains together with the alpha 5 chain. Large deletions involving the COL4A5 and COL4A6 genes have been found in rare cases of diffuse leiomyomatosis associated with Alport syndrome.

Web of Science

researchmap

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

We first isolated and characterized genomic DNA fragments that cover the 5' flanking sequences of COL4A3 and COL4A4 encoding the human basement membrane alpha 3(IV) and alpha 4(IV) collagen chains, respectively. Nucleotide sequence analysis indicated that the two genes are arranged head-to-head. To determine transcription start site for COL4A4 gene, we performed RACE and RNase protection assays, indicating that there are two alternative transcripts presumably derived from two different promoters. Interestingly, one transcription start site (from exon 1') of COL4A4 is only 5 bp away from the reported transcription start site of COL4A3, whereas the other transcript (from exon 1) starts 373 nucleotides downstream from the first one, generating the two kinds of transcripts that differ in the 5' UTR regions. Expression of these two transcripts appears tissue-specific; exon 1 transcript was expressed predominantly in epithelial cells, while exon 1' transcript showed rather ubiquitous and low expression. The nucleotide sequence of the promoter region is composed of dense CpG dinucleotides, GC boxes, CTC boxes and a CCAAT box but no TATA box. These results provide information to delineate the promoter activity for the tissue-specific expression of the six type IV collagen genes and basement membrane assembly in different tissues and organs. (C) 1998 Federation of European Biochemical Societies.

DOI： 10.1016/S0014-5793(98)00128-8

Web of Science

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

Language：English   Publishing type：Research paper, summary (international conference)   Publisher：FEDERATION AMER SOC EXP BIOL  

Web of Science

researchmap

Language：Japanese   Publisher：(一社)日本解剖学会  

researchmap

J-GLOBAL

researchmap

Language：Japanese  

DOI： 10.1111/j.1447-073X.2007.00202.x

J-GLOBAL

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：Japanese   Publisher：The Japanese Society for Connective Tissue  

CiNii Article

CiNii Books

researchmap

Language：English   Publishing type：Research paper, summary (international conference)   Publisher：GUSTAV FISCHER VERLAG  

Web of Science

researchmap

Language：English   Presentation type：Symposium, workshop panel (nominated)  

researchmap

Language：English   Presentation type：Symposium, workshop panel (nominated)  

researchmap