A Sec14 domain protein is required for photoautotrophic growth and chloroplast vesicle formation in <i>Arabidopsis thaliana</i>
Alexander P. Hertle, José G. García‐Cerdán, Ute Armbruster, Robert M. Shih, Jimmy J. Lee, Winnie Wong, Krishna Niyogi
Abstract
Significance The light reactions of photosynthesis in algae and plants occur in thylakoid membranes within the chloroplast. Previous studies have implicated membrane contact sites, vesicle trafficking, and lipid-binding proteins in the formation of thylakoids at the chloroplast inner envelope, but the molecular basis of thylakoid biogenesis and maintenance remains enigmatic. Here we show that CPSFL1 is a chloroplast Sec14 domain protein that binds lipids and can transfer phosphoinositides between membranes in vitro. In the model plant Arabidopsis , CPSFL1 is necessary for the appearance of vesicles in chloroplasts. Our results provide molecular evidence supporting an essential role of chloroplast lipid and vesicle trafficking for photoautotrophic growth.