title: Engineering OsBAK1 gene as a molecular tool to improve rice architecture for high yield.
abstract: Generating a new variety of plant with erect-leaf is a critical strategy to improve rice grain yield, as plants with this trait can be dense-planted. The erect-leaf is a significant morphological trait partially regulated by Brassinosteroids (BRs) in rice plants. So far, only a few genes can be used for molecular breeding in rice. Here, we identified OsBAK1 as a potential gene to alter rice architecture. Based on rice genome sequences, four closely related homologs of Arabidopsis BAK1 (AtBAK1) gene were amplified. Phylogenetic analysis and suppression of a weak Arabidopsis mutant bri1-5 indicated that OsBAK1 (Os08g0174700) is the closest relative of AtBAK1. Genetic, physiological, and biochemical analyses all suggest that the function of OsBAK1 is conserved with AtBAK1. Overexpression of a truncated intracellular domain of OsBAK1, but not the extracellular domain of OsBAK1, resulted in a dwarfed phenotype, similar to the rice BR-insensitive mutant plants. The expression of OsBAK1 changed important agricultural traits of rice such as plant height, leaf erectness, grain morphologic features, and disease resistance responses. Our results suggested that a new rice variety with erect-leaf and normal reproduction can be generated simply by suppressing the expression level of OsBAK1. Therefore, OsBAK1 is a potential molecular breeding tool for improving rice grain yield by modifying rice architecture.
authors.affiliation: Research Center for Molecular & Developmental Biology, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Yun-Yuan
authors.initials: YY
authors.lastname: Xu
authors.forename: Wei
authors.initials: W
authors.lastname: Luo
authors.forename: Ya-Ju
authors.initials: YJ
authors.lastname: Liu
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Xu
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.forename: Kang
authors.initials: K
authors.lastname: Chong
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics; D001947:Breeding; D018506:Gene Expression Regulation, Plant; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D018749:RNA, Plant; C463660:BAK1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases