Supplement to Plant and Cell Physiology Vol. 49
Conference information
Host: The Japanese Society of Plant Physiologists
PSI Cyclic Electron Transport During Early Chloroplast Development
Pages 0116
Details
Host: The Japanese Society of Plant Physiologists
Pages 0116
Photosystem I (PSI) cyclic electron transport is essential for photosynthesis and photoprotection. In higher plants, the ferredoxin-dependent pathway is the main route in PSI cyclic electron transport. Overexpression of PGR5, which is essential for this pathway, delayed early chloroplast biogenesis as a result of enhanced activity of PSI cyclic electron transport.
During chloroplast biogenesis, activity of PTOX is essential to activate carotenoid synthesis. PTOX is a homolog of the mitochondrial alternative oxidase (AOX) and has been proposed to serve as the terminal oxidase in chlororespiration. An Arabidopsis mutant, immutans (im), which is defective in PTOX activity, shows a variegated phenotype.
We evaluated an effect of a defect in PSI cyclic electron transport on the im phenotype. In the double mutant im pgr5, the variegated phenotype was partially suppressed. From this result, it is suggested that PSI cyclic electron transport operates in early chloroplast biogenesis.
