Journal Article

A blue-light photoreceptor mediates the feedback regulation of photosynthesis

German Research Foundation, DFG, grants FOR1261, Physiologie cellulaire et végétale (LPCV) ; Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG) ; Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Magneschi, Leonardo, Humboldt State University (HSU), JSPS KAKENHI (JP15H05599, JP26251033 and JP16H06553), Mittag, Maria, NIBB Cooperative Research Program for the Okazaki Large Spectrograph, NEDO (P07015), ANR-12-BIME-0005,DiaDomOil,Domestication des diatomées pour la production de biocarburants, ANR-10-LABX-0

2016

Overview

In plants and algae, light serves both as the energy source for photosynthesis and a biological signal that triggers cellular responses via specific sensory photoreceptors. Red light is perceived by bilin-containing phytochromes and blue light by the flavin-containing cryptochromes and/or phototropins (PHOTs), the latter containing two photosensory light, oxygen, or voltage (LOV) domains. Photoperception spans several orders of light intensity, ranging from far below the threshold for photosynthesis to values beyond the capacity of photosynthetic CO2 assimilation. Excess light may cause oxidative damage and cell death, processes prevented by enhanced thermal dissipation via high-energy quenching (qE), a key photoprotective response. Here we show the existence of a molecular link between photoreception, photosynthesis, and photoprotection in the green alga Chlamydomonas reinhardtii. We show that PHOT controls qE by inducing the expression of the qE effector protein LHCSR3 (light-harvesting complex stress-related protein 3) in high light intensities. This control requires blue-light perception by LOV domains on PHOT, LHCSR3 induction through PHOT kinase, and light dissipation in photosystem II via LHCSR3. Mutants deficient in the PHOT gene display severely reduced fitness under excessive light conditions, indicating that the sensing, utilization, and dissipation of light is a concerted process that plays a vital role in microalgal acclimation to environments of variable light intensities.

• Publisher: Nature Publishing Group,CCSD,Nature Publishing Group UK
• Subject: 38 / 38/1 / 631/208/200 / 631/449/1734/2687 / 631/80/86 / 82 / 96 / Acclimatization / Acclimatization - radiation effects / Algae / Apoptosis / Aquatic plants / Biochemistry, Molecular Biology / Carbon dioxide / Carotenoids / Cell Survival / Cell Survival - radiation effects / Chlamydomonas reinhardtii / Chlamydomonas reinhardtii - genetics / Chlamydomonas reinhardtii - metabolism / Chlamydomonas reinhardtii - radiation effects / Chloroplasts / Color / Cyanobacteria / Energy sources / Feedback, Physiological / Feedback, Physiological - radiation effects / Humanities and Social Sciences / Kinases / letter / Life Sciences / Light / Light intensity / Light Signal Transduction / Light Signal Transduction - radiation effects / Light-Harvesting Protein Complexes / Light-Harvesting Protein Complexes - biosynthesis / Light-Harvesting Protein Complexes - metabolism / multidisciplinary / Photoreception / Photoreceptors / Photosynthesis / Photosynthesis - radiation effects / Photosynthesis research / Photosystem II Protein Complex / Photosystem II Protein Complex - metabolism / Phototropins / Phototropins - chemistry / Phototropins - genetics / Phototropins - metabolism / Physiological aspects / Physiological regulation / Protein Kinases / Protein Kinases - chemistry / Protein Kinases - metabolism / Proteins / Science
• ISBN: 0003835459000