Blue light-induced phosphorylation of Arabidopsis cryptochrome 1 is essential for its photosensitivity  

作　　者：Lin Gao Qing Liu Ming Zhong Nannan Zeng Weixian Deng Yaxing Li Dong Wang Siyuan Liu Qin Wang 

机构地区：[1]College of Life Sciences,Basic Forestry and Proteomics Research Center,Fujian Agriculture and Forestry University,Fuzhou,350002 China [2]School of Life Sciences,State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources,South China Agricultural University,Guangzhou,510642 China [3]Key Laboratory of Ministry of Education for Genetics,Breeding and Multiple Utilization of Crops,College of Agriculture,Fujian Agriculture and Forestry University,Fuzhou,350002 China [4]Department of Biological Chemistry,David Geffen School of Medicine,University of California Los Angeles,Los Angeles,CA,90095 USA

出　　处：《Journal of Integrative Plant Biology》2022年第9期1724-1738,共15页植物学报（英文版）

基　　金：supported in part by the National Natural Science Foundation of China(31970265 and 31801018);the Natural Science Foundation of Guangdong Province(2022A1515011002);the National Key Research and Development Program of China(2020YFA0509700)。

摘　　要：Plants possess two cryptochrome photoreceptors,cryptochrome 1(CRY1)and cryptochrome 2(CRY2),that mediate overlapping and distinct physiological responses.Both CRY1 and CRY2 undergo blue light-induced phosphorylation,but the molecular details of CRY1 phosphorylation remain unclear.Here we identify 19 in vivo phosphorylation sites in CRY1 using mass spectrometry and systematically analyze the physiological and photobiochemical activities of CRY1 variants with phosphosite substitutions.We demonstrate that nonphosphorylatable CRY1 variants have impaired phosphorylation,degradation,and physiological functions,whereasphosphomimeticvariants mimic the physiological functions of phosphorylated CRY1 to constitutively inhibit hypocotyl elongation.We further demonstrate that phosphomimetic CRY1 variants exhibit enhanced interaction with the E3 ubiquitin ligase COP1(CONSTITUTIVELY PHOTOMORPHOGENIC 1).This finding is consistent with the hypothesis that phosphorylation of CRY1 is required for COP1-dependent signaling and regulation of CRY1.We also determine that PHOTOREGULATORY PROTEIN KINASEs(PPKs)phosphorylate CRY1 in a blue light-dependent manner and that this phosphorylation is critical for CRY1 signaling and regulation.These results indicate that,similar to CRY2,blue light-dependent phosphorylation of CRY1 determines its photosensitivity.

关 键 词：ARABIDOPSIS blue light CRYPTOCHROME PHOSPHORYLATION PPK 

分 类 号：Q945[生物学—植物学]