Chlorophyll catabolism precedes changes in chloroplast structure and proteome during leaf senescence.

ABSTRACT: The earliest visual changes of leaf senescence occur in the chloroplast as chlorophyll is degraded and photosynthesis declines. Yet, a comprehensive understanding of the sequence of catabolic events occurring in chloroplasts during natural leaf senescence is still missing. Here, we combined confocal and electron microscopy together with proteomics and biochemistry to follow structural and molecular changes during Arabidopsis leaf senescence. We observed that initiation of chlorophyll catabolism precedes other breakdown processes. Chloroplast size, stacking of thylakoids, and efficiency of PSII remain stable until late stages of senescence, whereas the number and size of plastoglobules increase. Unlike catabolic enzymes, whose level increase, the level of most proteins decreases during sene

SUBMITTER: Tamary E 

PROVIDER: S-EPMC6508775 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature