title: Kinase activity of OsBRI1 is essential for brassinosteroids to regulate rice growth and development.
abstract: Brassinosteroids (BRs) are steroid hormones that participate in multiple biological processes. In this paper, we characterized a classic rice mutant Fn189 (dwarf54, d54) showing semi-dwarf stature and erect leaves. The coleoptile elongation and root growth was less affected in Fn189 than wild-type plant by the exogenous application of eBL, the most active form of BRs. Lamina joint inclination assay and morphological analysis in darkness further showed that Fn189 mutant plant was insensitive to exogenous eBL. Through map-based cloning, Fn189 was found to be a novel allelic mutant of the DWARF 61 (D61) gene, which encodes the putative BRs receptor OsBRI1. A single base mutation caused the I834F substitution in the OsBRI1 kinase domain. Consequently, kinase activity of OsBRI1 was found to decrease dramatically. Taken together, the kinase activity of OsBRI1 is essential for brassinosteroids to regulate normal plant growth and development in rice.
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Zhao
authors.forename: Chenxi
authors.initials: C
authors.lastname: Wu
authors.forename: Shoujiang
authors.initials: S
authors.lastname: Yuan
authors.forename: Liang
authors.initials: L
authors.lastname: Yin
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Qinglei
authors.initials: Q
authors.lastname: Zhao
authors.forename: Baohua
authors.initials: B
authors.lastname: Zhao
authors.forename: Xueyong
authors.initials: X
authors.lastname: Li
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D060406:Brassinosteroids / Q000378:metabolism* / Q000494:pharmacology; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018548:Cotyledon / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D003624:Darkness; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D010641:Phenotype; D010937:Plant Growth Regulators / Q000378:metabolism* / Q000494:pharmacology; D018515:Plant Leaves / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D016415:Sequence Alignment
chemical_list: D060406:Brassinosteroids; D010937:Plant Growth Regulators; C519615:BRI1 protein, Oryza sativa; D017346:Protein Serine-Threonine Kinases