title: The RLA1/SMOS1 Transcription Factor Functions with OsBZR1 to Regulate Brassinosteroid Signaling and Rice Architecture.
abstract: Brassinosteroids (BRs) are plant-specific steroid hormones that control plant growth and development. Recent studies have identified key components of the BR signaling pathway inArabidopsis thalianaand in rice (Oryza sativa); however, the mechanism of BR signaling in rice, especially downstream of GSK3/SHAGGY-like kinase (GSK2), remains unclear. Here, we identified a BR-insensitive rice mutant,reduced leaf angle1(rla1), and cloned the corresponding gene.RLA1was identical to the previously reportedSMALL ORGAN SIZE1(SMOS1), which was cloned from another allele.RLA1/SMOS1encodes a transcription factor with an APETALA2 DNA binding domain. Genetic analysis indicated that RLA1/SMOS1 functions as a positive regulator in the BR signaling pathway and is required for the function of BRASSINAZOLE-RESISTANT1 (OsBZR1). In addition, RLA1/SMOS1 can interact with OsBZR1 to enhance its transcriptional activity. GSK2 can interact with and phosphorylate RLA1/SMOS1 to reduce its stability. These results demonstrate that RLA1/SMOS1 acts as an integrator of the transcriptional complex directly downstream of GSK2 and plays an essential role in BR signaling and plant development in rice.
authors.affiliation: State Key Laboratory of Genetic Engineering and Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China.
authors.forename: Shenglong
authors.identifier: 0000-0002-3867-6693
authors.initials: S
authors.lastname: Qiao
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Shiyong
authors.initials: S
authors.lastname: Sun
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Wang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Genetic Engineering and Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China.
authors.forename: Chengxiang
authors.identifier: 0000-0002-4594-4203
authors.initials: C
authors.lastname: Li
authors.affiliation: State Key Laboratory of Genetic Engineering and Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Genetic Engineering and Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Genetic Engineering and Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China.
authors.forename: Linna
authors.initials: L
authors.lastname: Leng
authors.affiliation: Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Weisheng
authors.initials: W
authors.lastname: Tian
authors.affiliation: Biotechnology Research Institute/National Key Facility for Gene Resources and Gene Improvement, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Tiegang
authors.initials: T
authors.lastname: Lu
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China xlwang@mail.hzau.edu.cn.
authors.forename: Xuelu
authors.identifier: 0000-0003-2003-1077
authors.initials: X
authors.lastname: Wang
mesh_terms: D001665:Binding Sites; D060406:Brassinosteroids / Q000378:metabolism*; D003001:Cloning, Molecular; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D012275:Oryza / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D060406:Brassinosteroids; D010940:Plant Proteins; D014157:Transcription Factors