Evolution of Proton Driving Force Control Enabling C4 Photosynthesis

2021 Fiscal Year Final Research Report

• Project Area: New Photosynthesis : Reoptimization of the solar energy conversion system
• Project/Area Number: 16H06557
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Biological Sciences
• Research Institution: Kwansei Gakuin University
• Principal Investigator: Munekage Yuri 関西学院大学, 生命環境学部, 准教授 (30423247)
• Co-Investigator(Kenkyū-buntansha): 松田 祐介 関西学院大学, 生命環境学部, 教授 (30291975) ; 古本 強 龍谷大学, 農学部, 教授 (30313208)
• Project Period (FY): 2016-06-30 – 2021-03-31
• Keywords: 光合成 / 進化 / プロトン駆動力

Outline of Final Research Achievements

In this study, we have shown that, of the two cyclic electron transfer pathways, the NDH pathway primarily contributes to the generation of the proton driving force required for ATP synthesis through its increased expression and activity along with C4 evolution in genus Flaveria. In the C4 Flaveria bidentis, CP12-3 binds to GAPDH and is suggested to be involved in the regulation of the Calvin-Benson cycle, which partially functions in the chloroplast of the mesophyll cell under high light condition. In marine diatoms, Bestrophin-like membrane proteins, including newly found paralogs, were identified and some of them were localized at the thylakoid membrane penetrating the pyrenoid, indicative of their role to be a part of a proton-driven force regulator linked with the biophysical CO2 concentrating mechanism.

Free Research Field

植物生理

Academic Significance and Societal Importance of the Research Achievements

本領域では、植物の持つ光合成の潜在能力を引き出すための戦略を示すことが目標の一つである。本研究ではCO2濃縮を可能にした特殊なプロトン駆動力制御システムの一端が明らかになった。このような植物の進化過程で実際に起こり得たプロトン駆動力制御システムの改変過程を模倣することで、過酷な環境下で高い光合成活性を維持するための光合成改良につなげることができる。