title: Photosystem I cyclic electron flow via chloroplast NADH dehydrogenase-like complex performs a physiological role for photosynthesis at low light.
abstract: Cyclic electron transport around photosystem I (PS I) was discovered more than a half-century ago and two pathways have been identified in angiosperms. Although substantial progress has been made in understanding the structure of the chloroplast NADH dehydrogenase-like (NDH) complex, which mediates one route of the cyclic electron transport pathways, its physiological function is not well understood. Most studies focused on the role of the NDH-dependent PS I cyclic electron transport in alleviation of oxidative damage in strong light. In contrast, here it is shown that impairment of NDH-dependent cyclic electron flow in rice specifically causes a reduction in the electron transport rate through PS I (ETR I) at low light intensity with a concomitant reduction in CO2 assimilation rate, plant biomass and importantly, grain production. There was no effect on PS II function at low or high light intensity. We propose a significant physiological function for the chloroplast NDH at low light intensities commonly experienced during the reproductive and ripening stages of rice cultivation that have adverse effects crop yield.
authors.affiliation: Center for Environment, Health and Field Sciences, Chiba University, 6-2-1 Kashiwa-no-ha, Kashiwa, Chiba 277-0882, Japan.|PRESTO, JST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Yamori
authors.affiliation: Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.|CREST, JST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Shikanai
authors.affiliation: Department of Applied Science, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, Miyagi 981-8555, Japan.|CREST, JST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Amane
authors.initials: A
authors.lastname: Makino
mesh_terms: D000483:Alleles; D018533:Biomass; D002736:Chloroplasts / Q000378:metabolism*; D004579:Electron Transport; D008027:Light; D009154:Mutation; D009245:NADH Dehydrogenase / Q000378:metabolism*; D012275:Oryza / Q000235:genetics / Q000378:metabolism; D010788:Photosynthesis; D045331:Photosystem I Protein Complex / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D045331:Photosystem I Protein Complex; D010940:Plant Proteins; D009245:NADH Dehydrogenase