Reversible SUMOylation of FHY1 Regulates Phytochrome A Signaling in Arabidopsis  

作　　者：Gao-Ping Qu Hong Li Xiao-Li Lin Xiangxiong Kong Zi-Liang Hu Yin Hua Jin Yu Liu Hang-Lin Song Dae Heon Kim Rongcheng Lin Jigang Li Jing Bo Jin 

机构地区：[1]Key Laboratory of Plant Molecular Physiology,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China [2]University of the Chinese Academy of Sciences,Beijing 100049,China [3]State Key Laboratory of Plant Physiology and Biochemistry,College of Biological Sciences,China Agricultural University,Beijing 100193,China [4]Yanbian Academy of Agriculture Sciences,Yanji 133001,China [5]Department of Biology,Sunchon National University,Sunchon 57922,South Korea [6]Key Laboratory of Photobiology,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China

出　　处：《Molecular Plant》2020年第6期879-893,共15页分子植物（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(grant nos.31670186 and 31870238);the Chinese Academy of Sciences(ZDRW-ZS-2019-2-0101,KFJ-STS-ZDTP-076-1,and The Innovative Academy of Seed Design).

摘　　要：In response to far-red light(FR),FAR-RED ELONGATED HYPOCOTYL 1(FHY1)transports the photoactivated phytochrome A(phyA),the primary FR photoreceptor,into the nucleus,where it initiates FR signaling in plants.Light promotes the 26S proteasome-mediated degradation of FHY1,which desensitizes FR signaling,but the underlying regulatory mechanism remains largely unknown.Here,we show that reversible SUMOylation of FHY1 tightly regulates this process.Lysine K32(K32)and K103 are major SUMOylation sites of FHY1.We found that FR exposure promotes the SUMOylation of FHY1,which accelerates its degradation.Furthermore,we discovered that ARABIDOPSIS SUMO PROTEASE 1(ASP1)interacts with FHY1 in the nucleus under FR and facilitates its deSUMOylation.FHY1 was strongly SUMOylated and its protein level was decreased in the asp1-1 loss-of-function mutant compared with that in the wild type under FR.Consistently,asp1-1 seedlings exhibited a decreased sensitivity to FR,suggesting that ASP1 plays an important role in the maintenance of proper FHY1 levels under FR.Genetic analysis further revealed that ASP1 regulates FR signaling through an FHY1-and phyA-dependent pathway.Interestingly,We found that continuous FR inhibits ASP1 accumulation,perhaps contributing to the desensitization of FR signaling.Taken together,these results indicate that FR-induced SUMOylation and ASP1-dependent deSUMOylation of FHY1 represent a key regulatory mechanism that fine-tunes FR signaling.

关 键 词：ARABIDOPSIS PHOTOMORPHOGENESIS FHY1 SUMO ASP1 

分 类 号：Q94[生物学—植物学]