title: BAK1 directly regulates brassinosteroid perception and BRI1 activation.
abstract: Plants utilize plasma membrane-localized receptor-like kinases (RLKs) to sense extracellular signals to coordinate growth, development, and innate immune responses. BAK1 regulates multiple signaling pathways acting as a co-receptor of several distinct ligand-binding RLKs. It has been debated whether BAK1 serves as an essential regulatory component or only a signal amplifier without pathway specificity. This issue has been clarified recently. Genetic and structural analyses indicated that BAK1 and its homologs play indispensible roles in mediating brassinosteroid (BR) signaling pathway by directly perceiving the ligand BR and activating the receptor of BR, BRI1. The mechanism revealed by these studies now serves as a paradigm for how a pair of RLKs can function together in ligand binding and subsequent initiation of signaling. [Figure: see text] Jia Li (Corresponding author).
authors.affiliation: Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.
authors.forename: Kai
authors.initials: K
authors.lastname: He
authors.forename: Shengbao
authors.initials: S
authors.lastname: Xu
authors.forename: Jia
authors.initials: J
authors.lastname: Li
mesh_terms: D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D060406:Brassinosteroids / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D060406:Brassinosteroids; D011494:Protein Kinases; C463660:BAK1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases
keywords: Arabidopsis; BAK1; BRI1; brassinosteroid; co-receptor; extracellular domain; leucine-rich repeat; receptor; receptor-like kinase