title: Strigolactone/MAX2-induced degradation of brassinosteroid transcriptional effector BES1 regulates shoot branching.
abstract: Strigolactones (SLs), a class of the most recently identified terpenoid phytohormones, play essential roles in plant development, specifically in suppressing shoot branching. MAX2, a subunit of an SCF E3 ligase and a positive regulator that inhibits shoot branching, is likely a key SL signaling component. Here, we provide genetic and biochemical evidence to demonstrate that BES1 interacts with MAX2 and acts as its substrate to regulate SL-responsive gene expression. Additional AtD14, a putative receptor of SLs, can promote BES1 degradation. Knockdown of BES1 and its homologs dramatically suppressed the branching phenotype of max2-1 mutant. These results portray an SL signaling cascade from the putative receptor to downstream transcription factors. In addition, we demonstrate that the SL and brassinosteroid (BR) signaling pathways distinctly regulate the same transcription factor, BES1, to control specific developmental processes.
authors.affiliation: State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, 200433 Shanghai, PRC.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, 200433 Shanghai, PRC.
authors.forename: Shiyong
authors.initials: S
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, 200433 Shanghai, PRC.
authors.forename: Wenjiao
authors.initials: W
authors.lastname: Zhu
authors.affiliation: School of Agriculture and Biology, Shanghai Jiao Tong University, 200240 Shanghai, PRC.
authors.forename: Kunpeng
authors.initials: K
authors.lastname: Jia
authors.affiliation: School of Agriculture and Biology, Shanghai Jiao Tong University, 200240 Shanghai, PRC.
authors.forename: Hongquan
authors.initials: H
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, 200433 Shanghai, PRC. Electronic address: xueluw@gmail.com.
authors.forename: Xuelu
authors.initials: X
authors.lastname: Wang
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D060406:Brassinosteroids / Q000494:pharmacology; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins; D005453:Fluorescence; D018506:Gene Expression Regulation, Plant; D007091:Image Processing, Computer-Assisted; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010937:Plant Growth Regulators / Q000494:pharmacology*; D018520:Plant Shoots / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D059748:Proteolysis / Q000187:drug effects*; D015398:Signal Transduction / Q000187:drug effects; D020798:Two-Hybrid System Techniques; D025801:Ubiquitin / Q000378:metabolism; D054875:Ubiquitination
chemical_list: D029681:Arabidopsis Proteins; C456160:BES1 protein, Arabidopsis; D060406:Brassinosteroids; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C435920:MAX2 protein, Arabidopsis; D009687:Nuclear Proteins; D010937:Plant Growth Regulators; D025801:Ubiquitin