Sugar metabolism regulation by a photosynthesis-signaling factor and its evolution

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H03275
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 44030:Plant molecular biology and physiology-related
• Research Institution: Tokyo University of Science
• Principal Investigator: Nishihama Ryuichi 東京理科大学, 理工学部応用生物科学科, 教授 (70283455)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: Raf様キナーゼ / 光合成 / 糖代謝 / ゼニゴケ / シグナル伝達

Outline of Final Research Achievements

Molecular mechanisms of the protein kinase PRAF, which functions in coordinating growth and metabolism with photosynthetic activity in Marchantia polymorpha, were investigated. PRAF belongs to Raf-like kinases and is phosphorylated in a photosynthetic activity-dependent manner. Disruption of the PRAF gene causes sugar metabolism defects and severely inhibits growth. This study demonstrated that multimerization with other PRAF molecules via the multimerization module PB1 domain present on the N-terminus of the protein is essential for its own phosphorylation and function. It was also suggested that the PB1 domain is unnecessary for the granule formation of PRAF proteins, and that granules are formed by phase separation. In addition, candidate target proteins of PRAF were identified.

Free Research Field

植物生理学、分子遺伝学、細胞生物学

Academic Significance and Societal Importance of the Research Achievements

光合成を行う植物にとって、成長や代謝などの生命現象を光合成の活性と調和させる必要がある。しかしその仕組みは多様であり、解明すべき点が数多く残されている。本研究では、光合成駆動の刺激を伝えるタンパク質リン酸化酵素PRAFの解析を通して、その一端を明らかにした。植物は進化を通してPRAFを保持しているため、その機能は植物に共通したものであると考えられ、本研究の成果は農業、園芸、環境保全等に活用できる知見であると考えられる。