Photosynthesis versus light: Structure-function of damaged Photosystem II – PSIIvsLight

Light is the substrate of photosynthesis, allowing fixation of CO2 from the atmosphere, but it also damages the photosynthetic apparatus. Photosystem II (PSII) is the primary victim of this damage in a process termed photoinhibition. Despite being a major limiting factor to plant and algal productivity, photoinhibition and in particular its molecular origins are poorly understood. Taking advantage of the recent breakthroughs in characterisation of the photoinhibition-related energy dissipation phenomenon “qI”, the project PSIIvsLight aims to unravel the physiological, structural, and functional consequences of PSII damage. Using a multifaceted approach combining genetics, functional essays in vivo, ultrafast biophysics, and structural biology, the project tries to tackle outstanding questions in photoinhibition: is qI quenching photoprotective and what is its physicochemical mechanism? what is the site and mechanism of initial light-induced damage, and what structural consequences does it bear? what is the involvement of PSII cyclic electron flow in damage prevention? Shedding light on the damage origins will advance large-scale phenotyping and allow developing strategies to improve plant fitness in field conditions.