Photooligomerization Determines Photosensitivity and Photoreactivity of Plant Cryptochromes  

作　　者：Qing Liu Tiantian Su Wenjin He Huibo Ren Siyuan Liu Yadi Chen Lin Gao Xiaohua Hu Haoyue Lu Shijiang Cao Ying Huang Xu Wang Qin Wang Chentao Lin 

机构地区：[1]Basic Forestry and Proteomics Research Center,UCLA-FAFU Joint Research Center on Plant Proteomics,College of Life Sciences,Fujian Agriculture and Forestry University,Fuzhou 350002,China [2]Department of Molecular,Cell&Developmental Biology,University of California,Los Angeles,CA 90095,USA [3]College of Life Sciences,Fujian Normal University,Fuzhou 350108,China [4]College of Forestry,Fujian Agriculture and Forestry University,Fuzhou 350002,China [5]These authors contributed equally to this article.

出　　处：《Molecular Plant》2020年第3期398-413,共16页分子植物（英文版）

基　　金：supported in part by the National Institutes of Health(GM56265 to C.L.);FAFU-ICE fund(KXGH17011 to Q.W.);FAFU OYIA fund(XJQ201801 to Q.W.);the National Natural Science Foundation of China(31801018 to Q.L.,31600228 to S.C.);the Natural Science Foundation of Fujian Province(2019J06014 to Q.W.,2018J01605 to Q.L.).

摘　　要：Plant and non-plant species possess cryptochrome(CRY)photoreceptors to mediate blue light regulation of development or the circadian clock.The blue light-dependent homooligomerization of Arabidopsis CRY2 is a known early photoreaction necessary for its functions,but the photobiochemistry and function of light-dependent homooligomerization and heterooligomerization of cryptochromes,collectively referred to as CRY photooligomerization,have not been well established.Here,we show that photooligomerization is an evolutionarily conserved photoreaction characteristic of CRY photoreceptors in plants and some non-plant species.Our analyses of the kinetics of the forward and reverse reactions of photooligomerization of Arabidopsis CRY1 and CRY2 provide a previously unrecognized mechanism underlying the different photosensitivity and photoreactivity of these two closely related photoreceptors.We found that photooligomerization is necessary but not sufficient for the functions of CRY2,implying that CRY photooligomerization is presumably accompanied by additional function-empowering conformational changes.We further demonstrated that the CRY2-CRY1 heterooligomerization plays roles in regulating functions of Arabidopsis CRYs in vivo.Taken together,these results suggest that photooligomerization is an evolutionarily conserved mechanism determining the photosensitivity and photoreactivity of plant CRYs.

关 键 词：light signaling PHOTOMORPHOGENESIS cryptochrome oligomerization 

分 类 号：Q94[生物学—植物学]