Yang cycle enzyme DEP1: its moonlighting functions in PSI and ROS production during leaf senescence  

作　　者：Chu-Kun Wang Xiu-Ming Li Fang Dong Cui-Hui Sun Wen-Li Lu Da-Gang Hu 

机构地区：[1]National Key Laboratory of Crop Biology,MOA Key Laboratory of Horticultural Crop Biology and Germplasm Innovation,College of Horticulture Science and Engineering,Shandong Agricultural University,Tai’an 271018,Shandong,China [2]Shandong Institute of Pomology,Key Laboratory for Fruit Biotechnology Breeding of Shandong,Tai’an 271000,Shandong,China

出　　处：《Molecular Horticulture》2022年第1期133-148,共16页分子园艺（英文）

基　　金：This work was supported by grants from the National Natural Science Foundation of China(32122080,31972375,31902049);Shandong Province(ZR2020YQ25).

摘　　要：Ethylene-mediated leaf senescence and the compromise of photosynthesis are closely associated but the underlying molecular mechanism is a mystery.Here we reported that apple DEHYDRATASE-ENOLASE-PHOSPHATASE-COMPLEX1(MdDEP1),initially characterized to its enzymatic function in the recycling of the ethylene precursor SAM,plays a role in the regulation of photosystem I(PSI)activity,activating reactive oxygen species(ROS)homeostasis,and negatively regulating the leaf senescence.A series of Y2H,Pull-down,CO-IP and Cell-free degradation biochemical assays showed that MdDEP1 directly interacts with and dephosphorylates the nucleus-encoded thylakoid protein MdY3IP1,leading to the destabilization of MdY3IP1,reduction of the PSI activity,and the overproduction of ROS in plant cells.These findings elucidate a novel mechanism that the two pathways intersect at MdDEP1 due to its moonlighting role in destabilizing MdY3IP1,and synchronize ethylene-mediated leaf senescence and the compromise of photosynthesis.

关 键 词：DEHYDRATASE-ENOLASE-PHOSPHATASE-COMPLEX1 Yang cycle Photosystem I ROS Leaf senescence PHOTOSYNTHESIS 

分 类 号：Q94[生物学—植物学]