Electrophysiological analysis that accelerates the isolation of key genes governing ion homeostasis of rice under salinity stress

• Project/Area Number: 17KK0152
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Environmental agriculture(including landscape science)
• Research Institution: Shinshu University
• Principal Investigator: Horie Tomoaki 信州大学, 学術研究院繊維学系, 教授 (90591181)
• Project Period (FY): 2018 – 2022
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥14,560,000 (Direct Cost: ¥11,200,000、Indirect Cost: ¥3,360,000)
• Keywords: イオン輸送 / 電気生理実験 / 耐塩性 / イネ / 電気生理解析 / 電気生理 / 遺伝資源 / イオン恒常性

Outline of Final Research Achievements

The purpose of this project was to attempt accelerating the identification of the genes that function in the transport/distribution of Na+ or K+ in rice by using non-invasive electrophysiological method called MIFE. Plans for a long-term visit and learning the skill of MIFE at the first project year have been nicely completed. However, the Covid-19 has ruined every plan for the next visit and MIFE experiments since 2020. Although the main purpose of this project was thus interfered unfortunately, some important collaborative experiments using the materials left in the first year were able to be performed by the help of the researchers in the foreign laboratory. MIFE experiments using rice genetic mutants, in which some transporter gene being a research target in my laboratory was disrupted, provided novel evidence that they directly mediate Na+ absorption at the root surface of cultivated rice plants.

Academic Significance and Societal Importance of the Research Achievements

MIFE法は、細胞・組織を介したイオンの流束を、非侵襲的かつ定量的に解析できる電気生理技術である。その汎用性は、植物に限らず微生物から動物細胞まで多岐にわたり、今回共同研究を実施した研究機関が祖となり、その活用が世界に広がりを見せている。残念ながら、感染症の影響で本来の研究目標を達成することはできなかったが、将来の日本への同測定系の導入を目指して、基本技術を自ら習得することができた。また、類似のプロジェクトを急遽実施しながら、本研究期間に重要な成果をあげることができた。更には、共同研究パートナーとは信頼関係を深め、今後も共同研究体制を継続することになった。近い将来日本にMIFEを導入したい。

Research Products

• [Int'l Joint Research] タスマニア大学(オーストラリア) (2019)
  • Year and Date: 2019-04-17
• [Journal Article] Functions and structure of roots and their contributions to salinity tolerance in plants (2021)
  • Author(s): Ichirou Karahara, Tomoaki Horie
  • Journal Title: Breeding Science Volume: 71 Issue: 1 Pages: 89-108
  • DOI: 10.1270/jsbbs.20123
  • NAID: 130007991336
  • ISSN: 1344-7610, 1347-3735
  • Peer Reviewed
• [Journal Article] Changes in Expression Level of OsHKT1;5 Alters Activity of Membrane Transporters Involved in K+ and Ca2+ Acquisition and Homeostasis in Salinized Rice Roots (2020)
  • Author(s): Mohammad Al Nayef, Celymar Solis, Lana Shabala, Takaaki Ogura, Zhonghua Chen, Jayakumar Bose, Frans J.M. Maathuis, Gayatri Venkataraman, Keitaro Tanoi, Min Yu, Meixue Zhou, Tomoaki Horie and Sergey Shabala
  • Journal Title: International Journal of Molecular Sciences Volume: 21 Issue: 14 Pages: 4882-4882
  • DOI: 10.3390/ijms21144882
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Remarks] 信州大学学術情報オンラインシステムSOAR
  • URL: http://soar-rd.shinshu-u.ac.jp/profile/ja.OFTmWUDU.html