Elucidation of a novel transpiration control system in plants that enables growth in hot and arid areas

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K22438
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 44:Biology at cellular to organismal levels, and related fields
• Research Institution: National Institute for Basic Biology
• Principal Investigator: Kanai Masatake 基礎生物学研究所, オルガネラ制御研究室, 特任助教 (30611488)
• Project Period (FY): 2019-06-28 – 2024-03-31
• Keywords: ヒマ / 耐暑性 / 耐乾性 / 蒸散

Outline of Final Research Achievements

Ricinus communis, which is native to East Africa, is a C3-type plant and has high temperature and drought tolerance, even though it is not a C4-type plant suited to hot and arid regions. In castor leaves, unique cells were found in the intra-leaf spaces below the stomatal cells. It was predicted that these specialized cells function as valves that open and close the pore space leading to the stomatal opening by changing their size, thereby providing a tight control by two valves in conjunction with the opening and closing of the stomatal opening. The expression profiles of the valve cells showed increased expression of transporters in the vaccuole membrane, suggesting that they function as valves in the leaf by precisely controlling the vacuole size.

Free Research Field

植物分子生物学

Academic Significance and Societal Importance of the Research Achievements

世界的な気温上昇と水不足の懸念から、高温・乾燥環境下においても健全に生育する作物の作出に向けた基礎研究が盛んに行われている。本研究はヒマの持つ、C3型植物でありながら、極めて強い高温・乾燥耐性を持つという特殊な現象に注目し、既存のモデルにない全く新しい蒸散制御システムの一端を明らかにした。将来的には、イネ、コムギといった食料として極めて重要なC3型植物に新規な蒸散制御システムを導入することで、食料問題の解決に資する新規戦略の提供となる。本研究の進展は、基礎研究の発展のみならず、将来的な食糧問題の解決に貢献するものになると考える。