Faculty Profiles - MURATA Yoshiyuki

Papers - MURATA Yoshiyuki

Division display 161 - 180 of about 242 ／ All the affair displays >>

Purification and characterization of cathepsin B from the gut of the sea cucumber (Stichopus japonicas)

Li-Ming Sun, Bei-Wei Zhu, Hai-tao Wu, Lei Yu, Da-Yong Zhou, Xiuping Dong, Jing-Feng Yang, Dong-Mei Li, Wen-Xiu Ye, Yoshiyuki Murata

Food Science and Biotechnology 20 ( 4 ) 919 - 925 2011.8

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

Cathepsin B from the gut of sea cucumber (Stichopus japonicas) was purified 81-fold with a 3% recovery by ammonium sulfate fractionation and a series chromatography on DEAE Sepharose CL-6B, Sephadex G-75, and TSK-Gel 3000 SWxl. The purified protein appeared as a single band on Native-PAGE but showed 2 bands of 23 and 26 kDa on SDS-PAGE. The optimum activity was found at pH 5.5 and 45°C. The enzyme was stable at pH 4. 5-6. 0 and the thermal stability was up to 50°C. The enzyme was strongly inhibited by E-64, iodoacetic acid, and antipain, demonstrating it is a cysteine protease containing sulfhydryl groups. Cu 2+, Ni 2+, and Zn 2+ could strongly inhibit the enzyme activity. The amino acid sequences of the purified enzyme were acquired by mass spectrometer, which did not show any homology with previously described cathepsins, suggesting it may be a novel member. © 2011 The Korean Society of Food Science and Technology and Springer Netherlands.

DOI： 10.1007/s10068-011-0127-1

Methyl jasmonate signaling and signal crosstalk between methyl jasmonate and abscisic acid in guard cells. Reviewed International journal

Munemasa S, Mori IC, Murata Y

Plant signaling & behavior 6 ( 7 ) 939 - 941 2011.7

Language：English Publishing type：Research paper (scientific journal) Publisher：Informa UK Limited

Plants tightly control stomatal aperture in response to various environmental changes. A drought-inducible phytohormone, abscisic acid (ABA), triggers stomatal closure and ABA signaling pathway in guard cells has been well studied. Similar to ABA, methyl jasmonate (MeJA) induces stomatal closure in various plant species but MeJA signaling pathway is still far from clear. Recently we found that Arabidopsis calcium dependent protein kinase CPK6 functions as a positive regulator in guard cell MeJA signaling and provided new insights into cytosolic Ca2+-dependent MeJA signaling. Here we discuss the MeJA signaling and also signal crosstalk between MeJA and ABA pathways in guard cells.

DOI： 10.4161/psb.6.7.15439

Mg-chelatase H subunit affects ABA signaling in stomatal guard cells, but is not an ABA receptor in Arabidopsis thaliana Reviewed

Tomo Tsuzuki, Koji Takahashi, Shin-ichiro Inoue, Yukiko Okigaki, Masakazu Tomiyama, Mohammad Anowar Hossain, Ken-ichiro Shimazaki, Yoshiyuki Murata, Toshinori Kinoshita

JOURNAL OF PLANT RESEARCH 124 ( 4 ) 527 - 538 2011.7

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

Mg-chelatase H subunit (CHLH) is a multifunctional protein involved in chlorophyll synthesis, plastid-to-nucleus retrograde signaling, and ABA perception. However, whether CHLH acts as an actual ABA receptor remains controversial. Here we present evidence that CHLH affects ABA signaling in stomatal guard cells but is not itself an ABA receptor. We screened ethyl methanesulfonate-treated Arabidopsis thaliana plants with a focus on stomatal aperture-dependent water loss in detached leaves and isolated a rapid transpiration in detached leaves 1 (rtl1) mutant that we identified as a novel missense mutant of CHLH. The rtl1 and CHLH RNAi plants showed phenotypes in which stomatal movements were insensitive to ABA, while the rtl1 phenotype showed normal sensitivity to ABA with respect to seed germination and root growth. ABA-binding analyses using H-3-labeled ABA revealed that recombinant CHLH did not bind ABA, but recombinant pyrabactin resistance 1, a reliable ABA receptor used as a control, showed specific binding. Moreover, we found that the rtl1 mutant showed ABA-induced stomatal closure when a high concentration of extracellular Ca2+ was present and that a knockout mutant of Mg-chelatase I subunit (chli1) showed the same ABA-insensitive phenotype as rtl1. These results suggest that the Mg-chelatase complex as a whole affects the ABA-signaling pathway for stomatal movements.

DOI： 10.1007/s10265-011-0426-x

Hydrogen [corrected] peroxide-dependent photocytotoxicity by phloxine B, a xanthene-type food colorant. International journal

Hang Qi, Hiroshi Takano, Yoji Kato, Qian Wu, Chiharu Ogata, Beiwei Zhu, Yoshiyuki Murata, Yoshimasa Nakamura

Biochimica et biophysica acta 1810 ( 7 ) 704 - 12 2011.7

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

BACKGROUND: Phloxine B (PhB; 2',4',5',7'-tetrabromo-4,5,6,7-tetrachloro-fluorescein), an artificial xanthene colorant, has been used as a red coloring agent in drugs and cosmetics as well as foods in some countries. However, little effort has been devoted to the study of this colorant as a potentially useful medicinal agent. METHODS: We investigated the daily light-induced photocytotoxicity of PhB in two human leukemia cells, HL-60 and Jurkat, and its underlying mechanisms by in vitro experiments using antioxidants. REUSLTS AND CONCLUSIONS: PhB inhibited cell proliferation more preferentially to HL-60 cells than to Jurkat cells. Co-treatment of catalase completely blocked the photocytotoxicity by PhB in HL-60 cells, whereas the effect of histidine was only partial, suggesting that hydrogen peroxide (H(2)O(2)), rather than singlet oxygen, might be a prerequisite for the PhB-induced HL-60 cell death. Actually, PhB produced a significant amount of H(2)O(2) in the media as well as in the cells in concentration- and light-dependent manners. Furthermore, methionine, a hypochlorous acid (HOCl) scavenger, also significantly attenuated the cytotoxicity in HL-60 cells, but not in Jurkat cells, indicating the involvement of myeloperoxidase (MPO)-dependent hypohalous acid formation during the photocytotoxicity. In vitro experiments revealed that halogenated tyrosine was generated from the reaction of bovine serum albumin with PhB and HL-60 cell lysate. The present findings suggested that PhB induced a differential photodynamic action in the MPO-containing leukemia cells through an H(2)O(2)-dependent mechanism. GENERAL SIGNIFICANCE: Our findings provide new insights into the molecular mechanisms underlying the PhB-induced apoptosis and also evaluated PhB as a promising PDT agent.

DOI： 10.1016/j.bbagen.2011.04.010

Involvement of Endogenous Abscisic Acid in Methyl Jasmonate-Induced Stomatal Closure in Arabidopsis International journal

Mohammad Anowar Hossain, Shintaro Munemasa, Misugi Uraji, Yoshimasa Nakamura, Izumi C. Mori, Yoshiyuki Murata

Plant Physiology 156 ( 1 ) 430 - 438 2011.5

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

<title>Abstract</title>
In this study, we examined the involvement of endogenous abscisic acid (ABA) in methyl jasmonate (MeJA)-induced stomatal closure using an inhibitor of ABA biosynthesis, fluridon (FLU), and an ABA-deficient Arabidopsis (Arabidopsis thaliana) mutant, aba2-2. We found that pretreatment with FLU inhibited MeJA-induced stomatal closure but not ABA-induced stomatal closure in wild-type plants. The aba2-2 mutation impaired MeJA-induced stomatal closure but not ABA-induced stomatal closure. We also investigated the effects of FLU and the aba2-2 mutation on cytosolic free calcium concentration ([Ca2+]cyt) in guard cells using a Ca2+-reporter fluorescent protein, Yellow Cameleon 3.6. In wild-type guard cells, FLU inhibited MeJA-induced [Ca2+]cyt elevation but not ABA-induced [Ca2+]cyt elevation. The aba2-2 mutation did not affect ABA-elicited [Ca2+]cyt elevation but suppressed MeJA-induced [Ca2+]cyt elevation. We also tested the effects of the aba2-2 mutation and FLU on the expression of MeJA-inducible VEGETATIVE STORAGE PROTEIN1 (VSP1). In the aba2-2 mutant, MeJA did not induce VSP1 expression. In wild-type leaves, FLU inhibited MeJA-induced VSP1 expression. Pretreatment with ABA at 0.1 μm, which is not enough concentration to evoke ABA responses in the wild type, rescued the observed phenotypes of the aba2-2 mutant. Finally, we found that in wild-type leaves, MeJA stimulates the expression of 9-CIS-EPOXYCAROTENOID DIOXYGENASE3, which encodes a crucial enzyme in ABA biosynthesis. These results suggest that endogenous ABA could be involved in MeJA signal transduction and lead to stomatal closure in Arabidopsis guard cells.

DOI： 10.1104/pp.111.172254

Involvement of extracellular oxidative burst in salicylic acid-induced stomatal closure in Arabidopsis International journal

MD. ATIQUR RAHMAN KHOKON, EIJI OKUMA, MOHAMMAD ANOWAR HOSSAIN, SHINTARO MUNEMASA, MISUGI URAJI, YOSHIMASA NAKAMURA, IZUMI C. MORI, YOSHIYUKI MURATA

Plant, Cell & Environment 34 ( 3 ) 434 - 443 2011.3

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

Salicylic acid (SA), a ubiquitous phenolic phytohormone, is involved in many plant physiological processes including stomatal movement. We analysed SA-induced stomatal closure, production of reactive oxygen species (ROS) and nitric oxide (NO), cytosolic calcium ion ([Ca²+](cyt)) oscillations and inward-rectifying potassium (K+(in)) channel activity in Arabidopsis. SA-induced stomatal closure was inhibited by pre-treatment with catalase (CAT) and superoxide dismutase (SOD), suggesting the involvement of extracellular ROS. A peroxidase inhibitor, SHAM (salicylhydroxamic acid) completely abolished SA-induced stomatal closure whereas neither an inhibitor of NADPH oxidase (DPI) nor atrbohD atrbohF mutation impairs SA-induced stomatal closures. 3,3'-Diaminobenzidine (DAB) and nitroblue tetrazolium (NBT) stainings demonstrated that SA induced H₂O₂ and O₂⁻ production. Guard cell ROS accumulation was significantly increased by SA, but that ROS was suppressed by exogenous CAT, SOD and SHAM. NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) suppressed the SA-induced stomatal closure but did not suppress guard cell ROS accumulation whereas SHAM suppressed SA-induced NO production. SA failed to induce [Ca²+](cyt) oscillations in guard cells whereas K+(in) channel activity was suppressed by SA. These results indicate that SA induces stomatal closure accompanied with extracellular ROS production mediated by SHAM-sensitive peroxidase, intracellular ROS accumulation and K+(in) channel inactivation.

DOI： 10.1111/j.1365-3040.2010.02253.x

The Arabidopsis Calcium-Dependent Protein Kinase, CPK6, Functions as a Positive Regulator of Methyl Jasmonate Signaling in Guard Cells International journal

Shintaro Munemasa, Mohammad Anowar Hossain, Yoshimasa Nakamura, Izumi C. Mori, Yoshiyuki Murata

Plant Physiology 155 ( 1 ) 553 - 561 2011.1

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

<title>Abstract</title>
Previous studies have demonstrated that methyl jasmonate (MeJA) induces stomatal closure dependent on change of cytosolic free calcium concentration in guard cells. However, these molecular mechanisms of intracellular Ca2+ signal perception remain unknown. Calcium-dependent protein kinases (CDPKs) function as Ca2+ signal transducers in various plant physiological processes. It has been reported that four Arabidopsis (Arabidopsis thaliana) CDPKs, CPK3, CPK6, CPK4, and CPK11, are involved in abscisic acid signaling in guard cells. It is also known that there is an interaction between MeJA and abscisic acid signaling in guard cells. In this study, we examined the roles of these CDPKs in MeJA signaling in guard cells using Arabidopsis mutants disrupted in the CDPK genes. Disruption of the CPK6 gene impaired MeJA-induced stomatal closure, but disruption of the other CDPK genes did not. Despite the broad expression pattern of CPK6, we did not find other remarkable MeJA-insensitive phenotypes in the cpk6-1 mutant. The whole-cell patch-clamp analysis revealed that MeJA activation of nonselective Ca2+-permeable cation channels is impaired in the cpk6-1 mutant. Consistent with this result, MeJA-induced transient cytosolic free calcium concentration increments were reduced in the cpk6-1 mutant. MeJA failed to activate slow-type anion channels in the cpk6-1 guard cells. Production of early signal components, reactive oxygen species and nitric oxide, in guard cells was elicited by MeJA in the cpk6-1 mutant as in the wild type. These results provide genetic evidence that CPK6 has a different role from CPK3 and functions as a positive regulator of MeJA signaling in Arabidopsis guard cells.

DOI： 10.1104/pp.110.162750

ABA signaling in stomatal guard cells: Lessons from Commelina and Vicia Invited Reviewed

Mori, I.C., Murata, Y.

Journal of Plant Research 124 ( 4 ) 477 - 87 2011

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

Abscisic acid (ABA) signaling mechanisms have been studied in a broad variety of plant species using complementary analyses, taking advantage of different methodologies suitable for each plant species. Early studies on ABA biosynthesis using Solanum lycopersicum mutants suggested an importance of ABA synthesis in stomatal closure. To understand ABA signaling in guard cells, cellular, biochemical and electrophysiological studies in Vicia faba and Commelina communis have been conducted, providing fundamental knowledge that was further reconfirmed by molecular genetic studies of Arabidopsis. In this article, examples of stomatal studies in several plants and prospects in ABA research are discussed.

DOI： 10.1007/s10265-011-0435-9

Photostability of lycopene dispersed in an aqueous solution. International journal

Masayuki Nishino, Takeshi Miuchi, Makoto Sakata, Atsushi Nishida, Yoshiyuki Murata, Yoshimasa Nakamura

Bioscience, biotechnology, and biochemistry 75 ( 7 ) 1389 - 91 2011

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

Lycopene dispersed in aqueous solutions with different dissolved oxygen contents was photo-irradiated by using a xenon weather meter, and the contents of lycopene and dissolved oxygen were measured. Both the degradation of lycopene and the consumption of dissolved oxygen followed a first-order kinetics model. There was a proportional relationship between the degradation content of lycopene and the consumption of dissolved oxygen. These results indicate that dissolved oxygen would also be involved in the photolysis of lycopene.

The Involvement of Intracellular Glutathione in Methyl Jasmonate Signaling in Arabidopsis Guard Cells International journal

AKTER Nasima, SOBAHAN Muhammad Abdus, HOSSAIN Mohammad Anowar, URAJI Misugi, NAKAMURA Yoshimasa, MORI Izumi C., MURATA Yoshiyuki

Agricultural and Biological Chemistry 74 ( 12 ) 2504 - 2506 2010.12

Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Society for Bioscience, Biotechnology, and Agrochemistry

We examined the involvement of intracellular glutathione (GSH) in methyl jasmonate (MeJA) signaling. The chlorina1-1 (ch1-1) mutation decreased GSH in guard cells and narrowed the stomatal aperture. GSH monoethyl ester increased intracellular GSH, diminishing this phenotype. GSH did not affect MeJA-induced reactive oxygen species production or cytosolic Ca²⁺ oscillation, suggesting that GSH modulates MeJA signaling downstream of production and oscillation.

DOI： 10.1271/bbb.100513

Other Link： https://jlc.jst.go.jp/DN/JALC/00361155234?from=CiNii

Chitosan-Induced Stomatal Closure Accompanied by Peroxidase-Mediated Reactive Oxygen Species Production in Arabidopsis International journal

KHOKON Md. Atiqur Rahman, URAJI Misugi, MUNEMASA Shintaro, OKUMA Eiji, NAKAMURA Yoshimasa, MORI Izumi C., MURATA Yoshiyuki

Agricultural and Biological Chemistry 74 ( 11 ) 2313 - 2315 2010.11

Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Society for Bioscience, Biotechnology, and Agrochemistry

Chitosan induced stomatal closure in wild type-plants and NADPH oxidase knock-out mutants (atrbohD atrbohF), and reactive oxygen species (ROS) production in wild-type guard cells. Closure and production were completely abolished by catalase and a peroxidase inhibitor. These results indicate that chitosan induces ROS production mediated by peroxidase, resulting in stomatal closure.

DOI： 10.1271/bbb.100340

Other Link： https://jlc.jst.go.jp/DN/JALC/00359674266?from=CiNii

Yeast Elicitor-Induced Stomatal Closure and Peroxidase-Mediated ROS Production in Arabidopsis

KHOKON Md. Atiqur Rahman, ANOWAR HOSSAIN Mohammad, MUNEMASA Shintaro, URAJI Misugi, NAKAMURA Yoshimasa, MORI Izumi C., MURATA Yoshiyuki

Plant and Cell Physiology 51 ( 11 ) 1915 - 1921 2010.11

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

Yeast elicitor (YEL) induces stomatal closure. We investigated reactive oxygen species (ROS) production, nitric oxide (NO) production and [Ca(2+)](cyt) oscillations to clarify YEL signaling in Arabidopsis guard cells. YEL induced ROS accumulation in guard cells. A peroxidase inhibitor [salicylhydroxamic acid (SHAM)] inhibited the stomatal closure and the ROS accumulation, but neither the atrbohD atrbohF mutation nor an NADPH oxidase inhibitor [diphenylene iodonium chloride (DPI)] had any effect. An NO scavenger [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO)] inhibited the YEL-induced stomatal closure and SHAM abolished NO production. YEL-elicited [Ca(2+)](cyt) oscillations were inhibited by SHAM but not by the atrbohD atrbohF mutation. These results indicate that YEL induces stomatal closure accompanied by ROS production mediated by peroxidases and NO production.

DOI： 10.1093/pcp/pcq145

The Effects of Methylglyoxal on Glutathione S-Transferase from Nicotiana tabacum International journal

HOQUE Md. Anamul, URAJI Misugi, BANU Mst. Nasrin Akhter, MORI Izumi C., NAKAMURA Yoshimasa, MURATA Yoshiyuki

Agricultural and Biological Chemistry 74 ( 10 ) 2124 - 2126 2010.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Society for Bioscience, Biotechnology, and Agrochemistry

Methylglyoxal (MG) is one of the aldehydes that accumulate in plants under environmental stress. Glutathione S-transferases (GSTs) play important roles, including detoxification, in the stress tolerance systems of plants. To determine the effects of MG, we characterized recombinant GST. MG decreased GST activity and thiol contents with increasing K_m. GST can serve as a target of MG modification, which is suppressed by application of reduced glutathione.

DOI： 10.1271/bbb.100393

Other Link： https://jlc.jst.go.jp/DN/JALC/00357984060?from=CiNii

Proline and Glycinebetaine Ameliorated NaCl Stress via Scavenging of Hydrogen Peroxide and Methylglyoxal but Not Superoxide or Nitric Oxide in Tobacco Cultured Cells International journal

BANU Mst. Nasrin Akhter, HOQOA Md. Anamul, WATANABE SUGIMOTO Megumi, ISLAM Mohammad Muzahidul, URAJI Misugi, MATSUOKA Ken, NAKAMURA Yoshimasa, MURATA Yoshiyuki

Agricultural and Biological Chemistry 74 ( 10 ) 2043 - 2049 2010.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Society for Bioscience, Biotechnology, and Agrochemistry

Efficient detoxification of the reactive oxygen species, nitric oxide (NO) and methylglyoxal (MG), provides protection against NaCl-induced damage in plants. To elucidate the protective mechanisms of proline and glycinebetaine (betaine) against NaCl stress, intracellular levels of hydrogen peroxide (H₂O₂), superoxide (O₂⁻), NO, and MG were investigated in tobacco Bright Yellow-2 cells. The Levels of H₂O₂, O₂⁻, NO and MG were higher in the short-term and long-term NaCl-stressed cells than in the non-stressed cells, whereas the O₂⁻ level was higher in the long-term stressed cells. Exogenous proline and betaine decreased the H₂O₂ level in both the short-term and the long-term NaCl-stressed cells and the MG level in the long-term NaCl-stressed cells, but did not change the O₂⁻ or NO levels. Under salt stress, both proline and betaine increased the transcription levels of glutathione peroxidase, which can contribute to the reduction of H₂O₂. In conclusion, proline and betaine mitigated salt stress via reduction of H₂O₂ accumulation during short-term incubation and via reduction of the accumulation of H₂O₂ and MG during long-term incubation.

DOI： 10.1271/bbb.100334

Other Link： https://jlc.jst.go.jp/DN/JALC/00357983889?from=CiNii

Cytosolic Alkalization and Cytosolic Calcium Oscillation in Arabidopsis Guard Cells Response to ABA and MeJA

ISLAM Mohammad Mahbub, HOSSAIN Mohammad Anowar, JANNAT Rayhanur, MUNEMASA Shintaro, NAKAMURA Yoshimasa, MORI Izumi C., MURATA Yoshiyuki

Plant and Cell Physiology 51 ( 10 ) 1721 - 1730 2010.10

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

Abscisic acid (ABA)- and methyl jasmonate (MeJA)-induced stomatal closure are accompanied by cytosolic alkalization in guard cells. However, it remains to be clarified how the alkalization functions in not only ABA signaling but also MeJA. We investigated cytosolic alkalization in guard cells during ABA-, MeJA- and Ca(2+)-induced stomatal closure of wild type, abi1-1, abi2-1, ost1-2 and coi1 using a pH-sensitive fluorescent dye, BCECF-AM. ABA induced cytosolic alkalization in guard cells of wild-type and coi1 but not in ost1-2 guard cells whereas MeJA elicited cytosolic alkalization in wild-type and ost1-2 guard cells but not in coi1. Neither ABA nor MeJA induced cytosolic alkalization in abi1-1 and abi2-1 guard cells. Exogenous Ca(2+) induced stomatal closure accompanied by cytosolic alkalization in guard cells of wild-type, abi1-1, abi2-1, ost1-2 and coi1 plants. An agent to acidify cytosol, butyrate, suppressed Ca(2+)-induced cytosolic alkalization and ABA-, MeJA- and Ca(2+)-induced cytosolic Ca(2+) oscillation in wild-type guard cells to prevent stomatal closure. These results indicate that cytosolic alkalization and cytosolic Ca(2+) oscillation coordinately function in ABA and MeJA signaling in Arabidopsis guard cells.

DOI： 10.1093/pcp/pcq131

Artificial Food Colorants Inhibit Superoxide Production in Differentiated HL-60 Cells International journal

QI Hang, KAWAGISHI Machiko, YOSHIMOTO Motoko, TAKANO Hiroshi, ZHU Beiwei, SHIMOISHI Yasuaki, TADA Mikiro, MURATA Yoshiyuki, NAKAMURA Yoshimasa

Agricultural and Biological Chemistry 74 ( 8 ) 1725 - 1728 2010.8

Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Society for Bioscience, Biotechnology, and Agrochemistry

We tested synthetic food colorants for their antioxidative potential by the in vitro superoxide generation assay in differentiated HL-60 cells in response to phorbol ester. Among the 12 colorants tested, such fluorescein-type red colorants as rose bengal showed potent inhibitory activity without any cytotoxicity under dark conditions. The intracellular accumulation and superoxide anion scavenging effect of rose bengal were at least partly involved in the inhibitory activity.

DOI： 10.1271/bbb.100314

Other Link： https://jlc.jst.go.jp/DN/JALC/00355048023?from=CiNii

Closing Plant Stomata Requires a Homolog of an Aluminum-Activated Malate Transporter

SASAKI Takayuki, MORI Izumi C., FURUICHI Takuya, MUNEMASA Shintaro, TOYOOKA Kiminori, MATSUOKA Ken, MURATA Yoshiyuki, YAMAMOTO Yoko

Plant and Cell Physiology 51 ( 3 ) 354 - 365 2010.3

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

Plant stomata limit both carbon dioxide uptake and water loss; hence, stomatal aperture is carefully set as the environment fluctuates. Aperture area is known to be regulated in part by ion transport, but few of the transporters have been characterized. Here we report that AtALMT12 (At4g17970), a homolog of the aluminum-activated malate transporter (ALMT) of wheat, is expressed in guard cells of Arabidopsis thaliana. Loss-of-function mutations in AtALMT12 impair stomatal closure induced by ABA, calcium and darkness, but do not abolish either the rapidly activated or the slowly activated anion currents previously identified as being important for stomatal closure. Expressed in Xenopus oocytes, AtALMT12 facilitates chloride and nitrate currents, but not those of organic solutes. Therefore, we conclude that AtALMT12 is a novel class of anion transporter involved in stomatal closure.

DOI： 10.1093/pcp/pcq016

Roles of AtTPC1, Vacuolar Two Pore Channel 1, in Arabidopsis Stomatal Closure

ISLAM Mohammad Mahbub, MUNEMASA Shintaro, HOSSAIN Mohammad Anowar, NAKAMURA Yoshimasa, MORI Izumi C., MURATA Yoshiyuki

Plant and Cell Physiology 51 ( 2 ) 302 - 311 2010.2

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

Abscisic acid (ABA) induces production of reactive oxygen species (ROS) and nitric oxide (NO), elevation of the cytosolic free calcium ion concentration ([Ca(2+)](cyt)) and cytosolic pH (pH(cyt)), and activation of S-type anion channels in guard cells, causing stomatal closure. To investigate whether Arabidopsis Two pore channel 1 (AtTPC1) that encodes the slow vacuolar (SV) channel is involved in stomatal closure, we examined stomatal movements and mobilization of second messengers in the attpc1-2 loss-of-function mutant in response to ABA, methyl jasmonate (MeJA) and Ca(2+). Both ABA and MeJA elicited production of ROS and NO, [Ca(2+)](cyt) oscillations, cytosolic alkalization and activation of S-type anion channel currents to lead to stomatal closure in the attpc1-2 mutant as well as the wild type. Unlike the wild type, in the attpc1-2 mutant exogenous Ca(2+) neither induced stomatal closure nor activated plasma membrane S-type anion channel currents despite [Ca(2+)](cyt) elevation. These results indicate that AtTPC1 functions in response to external Ca(2+) but not to ABA and MeJA in Arabidopsis guard cells and suggest that AtTPC1 could be involved in priming of plasma membrane S-type anion channels by external Ca(2+) in Arabidopsis guard cells.

DOI： 10.1093/pcp/pcq001

MAP kinases MPK9 and MPK12 are preferentially expressed in guard cells and positively regulate ROS-mediated ABA signaling Reviewed International coauthorship International journal

Fabien Jammes, Charlotte Song, Dongjin Shin, Shintaro Munemasa, Kouji Takeda, Dan Gu, Daeshik Cho, Sangmee Lee, Roberta Giordo, Somrudee Sritubtim, Nathalie Leonhardt, Brian E. Ellis, Yoshiyuki Murata, June M. Kwak

Proceedings of the National Academy of Sciences of the United States of America 106 ( 48 ) 20520 - 20525 2009.12

Language：English Publishing type：Research paper (scientific journal) Publisher：Proceedings of the National Academy of Sciences

Reactive oxygen species (ROS) mediate abscisic acid (ABA) signaling in guard cells. To dissect guard cell ABA-ROS signaling genetically, a cell type-specific functional genomics approach was used to identify 2 MAPK genes, MPK9 and MPK12, which are preferentially and highly expressed in guard cells. To provide genetic evidence for their function, Arabidopsis single and double TILLING mutants that carry deleterious point mutations in these genes were isolated. RNAi-based gene-silencing plant lines, in which both genes are silenced simultaneously, were generated also. Mutants carrying a mutation in only 1 of these genes did not show any altered phenotype, indicating functional redundancy in these genes. ABA-induced stomatal closure was strongly impaired in 2 independent RNAi lines in which both MPK9 and MPK12 transcripts were significantly silenced. Consistent with this result, mpk9-1/12-1 double mutants showed an enhanced transpirational water loss and ABA- and H(2)O(2)-insensitive stomatal response. Furthermore, ABA and calcium failed to activate anion channels in guard cells of mpk9-1/12-1, indicating that these 2 MPKs act upstream of anion channels in guard cell ABA signaling. An MPK12-YFP fusion construct rescued the ABA-insensitive stomatal response phenotype of mpk9-1/12-1, demonstrating that the phenotype was caused by the mutations. The MPK12 protein is localized in the cytosol and the nucleus, and ABA and H(2)O(2) treatments enhance the protein kinase activity of MPK12. Together, these results provide genetic evidence that MPK9 and MPK12 function downstream of ROS to regulate guard cell ABA signaling positively.

DOI： 10.1073/pnas.0907205106

Proline and Glycinebetaine Confer Cadmium Tolerance on Tobacco Bright Yellow-2 Cells by Increasing Ascorbate-Glutathione Cycle Enzyme Activities International journal

ISLAM Mohammad Muzahidul, HOQUE Md. Anamul, OKUMA Eiji, JANNAT Rayhanur, BANU Mst. Nasrin Akhter, JAHAN Md. Sarwar, NAKAMURA Yoshimasa, MURATA Yoshiyuki

Agricultural and Biological Chemistry 73 ( 10 ) 2320 - 2323 2009.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Society for Bioscience, Biotechnology, and Agrochemistry

Cadmium (Cd) stress significantly decreased membrane integrity and impaired the ascorbate (ASC)-glutathione (GSH) cycle in tobacco Bright Yellow-2 cells. Exogenous application of proline and glycinebetaine (betaine) significantly restored the membrane integrity and increased the activities of ASC-GSH cycle enzymes under Cd stress without maintenance of the rich ASC or GSH pools. Moreover, proline offered more efficient protection against Cd stress than betaine.

DOI： 10.1271/bbb.90305

Other Link： https://jlc.jst.go.jp/DN/JALC/00338802147?from=CiNii

　 PREV - NEXT 　

1
2
3
4
5
6
7
8
9
10
11
12
13