title: Integration of light- and brassinosteroid-signaling pathways by a GATA transcription factor in Arabidopsis.
abstract: Light and brassinosteroid (BR) antagonistically regulate the developmental switch from etiolation in the dark to photomorphogenesis in the light in plants. Here, we identify GATA2 as a key transcriptional regulator that mediates the crosstalk between BR- and light-signaling pathways. Overexpression of GATA2 causes constitutive photomorphogenesis in the dark, whereas suppression of GATA2 reduces photomorphogenesis caused by light, BR deficiency, or the constitutive photomorphogenesis mutant cop1. Genome profiling and chromatin immunoprecipitation experiments show that GATA2 directly regulates genes that respond to both light and BR. BR represses GATA2 transcription through the BR-activated transcription factor BZR1, whereas light causes accumulation of GATA2 protein and feedback inhibition of GATA2 transcription. Dark-induced proteasomal degradation of GATA2 is dependent on the COP1 E3 ubiquitin ligase, and COP1 can ubiquitinate GATA2 in vitro. This study illustrates a molecular framework for antagonistic regulation of gene expression and seedling photomorphogenesis by BR and light.
authors.affiliation: Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Xiao-Min
authors.initials: XM
authors.lastname: Luo
authors.forename: Wen-Hui
authors.initials: WH
authors.lastname: Lin
authors.forename: Shengwei
authors.initials: S
authors.lastname: Zhu
authors.forename: Jia-Ying
authors.initials: JY
authors.lastname: Zhu
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.forename: Xi-Ying
authors.initials: XY
authors.lastname: Fan
authors.forename: Menglin
authors.initials: M
authors.lastname: Cheng
authors.forename: Yaqi
authors.initials: Y
authors.lastname: Hao
authors.forename: Eunkyoo
authors.initials: E
authors.lastname: Oh
authors.forename: Miaomiao
authors.initials: M
authors.lastname: Tian
authors.forename: Lijing
authors.initials: L
authors.lastname: Liu
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Qi
authors.initials: Q
authors.lastname: Xie
authors.forename: Kang
authors.initials: K
authors.lastname: Chong
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Wang
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins; D050989:GATA2 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008027:Light; D035683:MicroRNAs / Q000235:genetics; D008954:Models, Biological; D009154:Mutation; D009687:Nuclear Proteins / Q000378:metabolism*; D052817:Phototrophic Processes / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D010937:Plant Growth Regulators / Q000378:metabolism; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic; D018749:RNA, Plant / Q000235:genetics; D015398:Signal Transduction; D013260:Steroids, Heterocyclic / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C454444:BZR1 protein, Arabidopsis; D017931:DNA Primers; D004268:DNA-Binding Proteins; D050989:GATA2 Transcription Factor; D035683:MicroRNAs; D009687:Nuclear Proteins; D010937:Plant Growth Regulators; D018749:RNA, Plant; D013260:Steroids, Heterocyclic; C471983:AT2G32950 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases