title: Mechanisms of signaling crosstalk between brassinosteroids and gibberellins.
abstract: Brassinosteroids (BRs) and Gibberellins (GAs) are two principal groups of growth-promoting phytohormones. Accumulating evidence supports that there are crosstalks between BR and GA signaling pathways. However, a molecular mechanism for direct signaling crosstalk between BRs and GAs was not revealed until recently. Works from three different groups demonstrated that an interaction between BZR1/BES1 and DELLAs, two groups of key transcriptional regulators from the BR and GA signaling pathways, respectively, mediates the direct signaling crosstalk between BRs and GAs in controlling cell elongation in Arabidopsis. It was shown that DELLA proteins not only affect the protein stability but also inhibit the transcriptional activity of BZR1. Thus, GAs promote cell elongation, at least in part, through releasing DELLA-mediated inhibition of BZR1. This review aims to introduce these recent advances in our understanding of how BRs and GAs coordinate to regulate plant growth and development at the molecular level.
authors.affiliation: School of Life Sciences and State Key Laboratory of Agrobiotechnology; The Chinese University of Hong Kong; Hong Kong SAR, PR China.
authors.forename: Qian-Feng
authors.initials: QF
authors.lastname: Li
authors.forename: Jun-Xian
authors.initials: JX
authors.lastname: He
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism; D060406:Brassinosteroids / Q000378:metabolism*; D049108:Cell Enlargement; D004268:DNA-Binding Proteins; D035264:Flowers / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D018525:Germination; D005875:Gibberellins / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism; D020239:Receptor Cross-Talk; D036226:Seedlings / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; C454444:BZR1 protein, Arabidopsis; D060406:Brassinosteroids; D004268:DNA-Binding Proteins; C109555:GAI protein, Arabidopsis; D005875:Gibberellins; D009687:Nuclear Proteins
keywords: BRASSINAZOLE- RESISTANT 1; BRI1-EMS-SUPPRESSOR 1; DELLAs; brassinosteroids; gibberellins; growth and development; signaling crosstalk