Photosynthesis begins with elementary school science, but in reality there are many unexplained parts of its mechanism.Moreover, there is a possibility that hints for solving various problems we have, including environmental problems, are hidden in the unexplained part. On September 9, Chiba University announced that it has elucidated a new physiological function of the cyclic electron transfer pathway that works in photosynthesis in a joint research with Tohoku University and Kyoto University.This result can be expected to contribute to the elucidation of the mechanism by which plants optimize their photosynthetic efficiency under various light environments, leading to increased production of crops and reduction of carbon dioxide in the atmosphere of the entire earth.
Plants convert light energy into chemical energy through electron transfer reactions.It is known that this electron transfer path includes a linear electron transfer path and a cyclic electron transfer path.The latter cyclic electron transfer pathway was discovered more than half a century ago, but the overall picture of its physiology remains unclear.It is known that there are a protein-dependent pathway called PGR5 and an NDH complex-dependent pathway consisting of multiple proteins in the cyclic electron transfer pathway of higher plants, and the NDH complex-dependent pathway is particularly summer. It has been argued that it is important for alleviating environmental stress such as strong light such as direct sunlight and dryness.
The research group analyzed rice, which is a major crop, using mutants of rice lacking the NDH complex.Using the latest method, we measured two electron transfer paths (linear electron transfer path and cyclic electron transfer path) and CO2 gas exchange at the same time. It became clear that it is important for optimizing the photosynthetic reaction under low light conditions such as twilight.
The results of this research were published in the online version of the British scientific journal "Scientific Reports" on September 2015, 9 (UK time).