Wednesday, July 10, 2019 - 12:00pm
Carnegie Institution for Science
Unraveling the establishment of energy dissipation during high light acclimation in Chlamydomonas reinhardtii
Energy dissipation of excess light energy as heat (Non-photochemical quenching, NPQ) is an essential photo protective mechanism active in photosynthetic organisms to prevent cell damage through reactive oxygen species. NPQ is constitutively active in vascular plants and dependents on the PsbS protein. In green algae like Chlamydomonas reinhardtii it only becomes activated upon high light (HL) acclimation and requires the HL dependent accumulation of the LHCSR3 and the UV-B dependent accumulation of the LHCSR1 protein. While LHCSR3 in C. reinhardtii has been understood as the functional orthologue of the vascular plant PsbS, the contribution of PsbS to NPQ in green algae is not clear yet. PsbS in algae accumulates transiently in dependence of UV-B and HL during the induction of a high NPQ, which suggests a photo protective function that may be required upon HL conditions when LHCSR1 and LHCSR3 are not sufficient for energy dissipation.