Understanding the molecular mechanism of B3-MAPKKK-mediated plant osmostress response

• Project/Area Number: 19K06713
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 44030:Plant molecular biology and physiology-related
• Research Institution: Tokyo University of Agriculture
• Principal Investigator: Sakata Yoichi 東京農業大学, 生命科学部, 教授 (50277240)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2021: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2020: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: ABA / 浸透圧 / SnRK2 / RAFカイネース / シロイヌナズナ / ヒメツリガネゴケ / 浸透圧応答 / RAF / エチレン受容体 / アブシジン酸 / B-RAF / B-MAPKKK / 浸透圧ストレス / Raf様キナーゼ / B3 MAPKKK / MAPKKK

Outline of Research at the Start

植物は乾燥ストレスに曝されると、それを細胞内の浸透圧変化として感知し、植物ホルモンであるABAを蓄積し、気孔閉鎖を始めとする様々な防御応答を発動する。この一連の応答では植物固有のリン酸化タンパク質SnRK2の活性化が重要であることが示されている。近年、ABAによるSnRK2の活性化における分子基盤は解明が進んだが、浸透圧による活性化機構については未だ不明な部分が多く残されている。本研究では、申請者の研究グループが初めて同定したSnRK2上流キナーゼ（ARK）を中心とした浸透圧によるSnRK2活性化機構の分子基盤を解明する。

Outline of Final Research Achievements

A protein kinase SnRK2 plays an essential role in osmostress responses of plants; however, a mechanism how SnRK2 is activated by osmostress was unknown. Our research group showed using the moss that B3-RAF is an upstream kinase of SnRK2 in ABA and osomostress signaling. In this research project we further showed that B3-RAF is evolutionarily conserved in Arabidopsis, which is a model plant of angiosperms, and also regulates osmostress-responsive SnRK2 activity via direct phosphorylation. Our research demonstrates that B3-RAF mediated osmostress-dependent SnRK2 activation is evolutionarily conserved among land plants. On the other hand, the mechanism by which B3-RAF is activated is suggested to be different between Arabidopsis and the moss.

Academic Significance and Societal Importance of the Research Achievements

本研究グループによる乾燥応答の制御因子としてのRAFの発見がシロイヌナズナRAFの機能解明につながったように、ヒメツリガネゴケの解析はコケ植物の知見にとどまらず、被子植物が有しながらもこれまで明らかにされてこなかった環境情報処理システムの解明に繋がることが期待できる。進行する地球規模の環境変化において、水環境に対する作物のレジリエンス向上は重要課題である。植物の水環境情報統御の分子基盤を明らかにしていくことは、食糧・エネルギー問題解決への基盤技術構築に貢献すると考える。

Research Products

• [Journal Article] Sensor histidine kinases mediate ABA and osmostress signaling in the moss Physcomitrium patens (2022)
  • Author(s): Tsukasa Toriyama, Akihisa Shinozawa, Yuki Yasumura, Masashi Saruhashi, Mayuka Hiraide, Shiori Ito, Hideyuki Matsuura, Keiko Kuwata, Mika Yoshida, Tadashi Baba, Izumi Yotsui, Teruaki Taji, Daisuke Takezawa, Yoichi Sakata
  • Journal Title: Current Biology Volume: 32 Issue: 1 Pages: 164-175
  • DOI: 10.1016/j.cub.2021.10.068
  • Peer Reviewed
• [Journal Article] MAP KINASE PHOSPHATASE1 promotes osmotolerance by suppressing PHYTOALEXIN DEFICIENT4-independent immunity (2022)
  • Author(s): Kohei Uchida, Masahiro Yamaguchi, Kazuki Kanamori, Hirotaka Ariga, Kazuho Isono, Takuma Kajino, Keisuke Tanaka, Yusuke Saijo, Izumi Yotsui, Yoichi Sakata, Teruaki Taji
  • Journal Title: Plant Physiology Volume: - Issue: 2 Pages: 1128-1138
  • DOI: 10.1093/plphys/kiac131
  • Peer Reviewed / Open Access
• [Journal Article] Mitochondrial Fission Complex Is Required for Long-Term Heat Tolerance of Arabidopsis (2022)
  • Author(s): Ryo Tsukimoto, Kazuho Isono, Takuma Kajino, Satoshi Iuchi, Akihisa Shinozawa, Izumi Yotsui, Yoichi Sakata, Teruaki Taji
  • Journal Title: Plant & cell physiology Volume: 63 Issue: 3 Pages: 296-304
  • DOI: 10.1093/pcp/pcab171
  • Peer Reviewed / Open Access
• [Journal Article] Decoding ABA and osmostress signalling in plants from an evolutionary point of view (2020)
  • Author(s): Komatsu Kenji、Takezawa Daisuke、Sakata Yoichi
  • Journal Title: Plant, Cell & Environment Volume: 43 Issue: 12 Pages: 2894-2911
  • DOI: 10.1111/pce.13869
  • Peer Reviewed
• [Journal Article] Activation of SnRK2 by Raf-like kinase ARK represents a primary mechanism of ABA and abiotic stress responses (2020)
  • Author(s): Islam Mousona、Inoue Takumi、Hiraide Mayuka、Khatun Nobiza、Jahan Akida、Kuwata Keiko、Katagiri Sotaro、Umezawa Taishi、Yotsui Izumi、Sakata Yoichi、Takezawa Daisuke
  • Journal Title: Plant Physiology Volume: 185 Issue: 2 Pages: 533-546
  • DOI: 10.1093/plphys/kiaa046
  • Peer Reviewed / Open Access
• [Journal Article] Genome-Wide Association Study and Genomic Prediction Elucidate the Distinct Genetic Architecture of Aluminum and Proton Tolerance in Arabidopsis thaliana (2020)
  • Author(s): Yuki Nakano, Kazutaka Kusunoki, Owen A. Hoekenga, Keisuke Tanaka, Satoshi Iuchi, Yoichi Sakata, Masatomo Kobayashi, Yoshiharu Y. Yamamoto, Hiroyuki Koyama, Yuriko Kobayashi
  • Journal Title: Front Plant Sci. Volume: 11 Pages: 1-16
  • DOI: 10.3389/fpls.2020.00405
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Arabidopsis Raf‐like kinases act as positive regulators of subclass III SnRK2 in osmostress signaling (2020)
  • Author(s): Shohei Katsuta 、Goro Masuda、Hyeokjin Bak、Akihisa Shinozawa、Yoshiaki Kamiyama、Taishi Umezawa、Daisuke Takezawa、Izumi Yotsui、Teruaki Taji、Yoichi Sakata
  • Journal Title: The Plant Journal Volume: 324 Issue: 2 Pages: 1064-1064
  • DOI: 10.1111/tpj.14756
  • Peer Reviewed / Open Access
• [Presentation] Arabidopsis B3-MAPKKKs are positive regulators of subclass III SnRK2 in osmostress signaling (2020)
  • Author(s): Goro Masuda, Shohei Katsuta, Hyeokjin Bak, Akihisa Shinozawa, Yoshiaki Kamiyama, Taishi Umezawa, Daisuke Takezawa, Izumi Yotsui, Teruaki Taji, Yoichi Sakata
  • Organizer: 植物生理学会年会
• [Presentation] B3-MAPKKKを介したsubclass Ⅲ SnRK2の活性制御機構の解析 (2019)
  • Author(s): 増田 悟郎, 勝田 祥平, 朴 赫鎭, 篠澤 章久, 神山 佳明, 梅澤 泰史, 竹澤 大輔 , 四井 いずみ , 太治 輝昭 , 坂田 洋一
  • Organizer: 植物学会年会