Delayed degradation of chlorophylls and photosynthetic proteins in Arabidopsis autophagy mutants during stress-induced leaf yellowing
- Authors
- Sakuraba, Yasuhito; Lee, Sang-Hwa; Kim, Ye-Sol; Park, Ohkmae K.; Hoertensteiner, Stefan; Paek, Nam-Chon
- Issue Date
- 7월-2014
- Publisher
- OXFORD UNIV PRESS
- Keywords
- Abiotic stress; Arabidopsis thaliana; autophagy; atg5; chlorophyll degradation; leaf senescence; stay-green
- Citation
- JOURNAL OF EXPERIMENTAL BOTANY, v.65, no.14, pp.3915 - 3925
- Indexed
- SCIE
SCOPUS
- Journal Title
- JOURNAL OF EXPERIMENTAL BOTANY
- Volume
- 65
- Number
- 14
- Start Page
- 3915
- End Page
- 3925
- URI
- https://scholar.korea.ac.kr/handle/2021.sw.korea/98088
- DOI
- 10.1093/jxb/eru008
- ISSN
- 0022-0957
- Abstract
- Plant autophagy, one of the essential proteolysis systems, balances proteome and nutrient levels in cells of the whole plant. Autophagy has been studied by analysing Arabidopsis thaliana autophagy-defective atg mutants, but the relationship between autophagy and chlorophyll (Chl) breakdown during stress-induced leaf yellowing remains unclear. During natural senescence or under abiotic-stress conditions, extensive cell death and early yellowing occurs in the leaves of atg mutants. A new finding is revealed that atg5 and atg7 mutants exhibit a functional stay-green phenotype under mild abiotic-stress conditions, but leaf yellowing proceeds normally in wild-type leaves under these conditions. Under mild salt stress, atg5 leaves retained high levels of Chls and all photosystem proteins and maintained a normal chloroplast structure. Furthermore, a double mutant of atg5 and non-functional stay-green nonyellowing1-1 (atg5 nye1-1) showed a much stronger stay-green phenotype than either single mutant. Taking these results together, it is proposed that autophagy functions in the non-selective catabolism of Chls and photosynthetic proteins during stress-induced leaf yellowing, in addition to the selective degradation of Chl-apoprotein complexes in the chloroplasts through the senescence-induced STAY-GREEN1/NYE1 and Chl catabolic enzymes.
- Files in This Item
- There are no files associated with this item.
- Appears in
Collections - Graduate School > Department of Life Sciences > 1. Journal Articles
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.