Calcium-dependent regulation of cyclic photosynthetic electron transfer by a CAS, ANR1, and PGRL1 complex.

International audienceCyclic photosynthetic electron flow (CEF) is crucial to photosynthesis because it participates in the control of chloroplast energy and redox metabolism, and it is particularly induced under adverse environmental conditions. Here we report that down-regulation of the chloroplast localized Ca(2+) sensor (CAS) protein by an RNAi approach in Chlamydomonas reinhardtii results in strong inhibition of CEF under anoxia. Importantly, this inhibition is rescued by an increase in the extracellular Ca(2+) concentration, inferring that CEF is Ca(2+)-dependent. Furthermore, we identified a protein, anaerobic response 1 (ANR1), that is also required for effective acclimation to anaerobiosis. Depletion of ANR1 by artificial microRNA expression mimics the CAS-depletion phenotype, and under anaerobic conditions the two proteins coexist within a large active photosystem I-cytochrome b(6)/f complex. Moreover, we provide evidence that CAS and ANR1 interact with each other as well as with PGR5-Like 1 (PGRL1) in vivo. Overall our data establish a Ca(2+)-dependent regulation of CEF via the combined function of ANR1, CAS, and PGRL1, associated with each other in a multiprotein complex

JUN Yong-Hoon, « Calendars and Calendrical Knowledge in Pre-modern Korea », 28 février 2017

Dans le cadre du séminaire de Sciences et savoirs de l’Asie orientale de la mondialisation de l'UMR CCJ, Catherine JAMI et Frédéric OBRINGER organisent une conférence intitulée « Calendars and Calendrical Knowledge in Pre-modern Korea » donnée par JUN Yong-Hoon (AKS) Mardi 28 février 2017 de 15h à 17h EHESS / Salle Elisabeth Allès 190 avenue de France 75013 Paris Calendars and Calendrical Knowledge in Pre-modern Korea This talk will start with a brief introduction to some annual calendars us..