Brassinosteroids(BRs) are essential phytohormones that shape rice architecture,grain development,and stress resilience by modulating leaf angle,stem elongation,tillering,and spikelet growth,all of which collectively i...Brassinosteroids(BRs) are essential phytohormones that shape rice architecture,grain development,and stress resilience by modulating leaf angle,stem elongation,tillering,and spikelet growth,all of which collectively influence light interception and yield formation(Manghwar et al.2022;Yuan et al.2022;Hou et al.2025;Li et al.2025).Although partial manipulation of BR signaling has recently gained attention as a strategy for ideotype breeding,the translation of BR biology into crop improvement remains hindered by an incomplete understanding of how BR responsiveness varies among elite japonica backgrounds.In this study,we uncovered pronounced differences in BR morphological responsiveness and transcriptional feedback between two widely used japonica cultivars,Taichung 65(TC65) and Zhonghua 11(ZH11),indicating that genetic background has substantial impacts on BR perception and signaling efficiency.Motivated by this finding,we developed a non-transgenic near-isogenic BR-insensitive line,d61-zh11,by introgressing the classical weak OsBRI1 allele(d61-1) from TC65 into the modern,genome-enabled ZH11 background.展开更多
Brassinosteroids(BRs) are a class of plant-specific steroidal hormones that play important roles in multiple biological processes. In this paper, a classic rice mutant gsor300084,showing erect leaves and semi-dwarf st...Brassinosteroids(BRs) are a class of plant-specific steroidal hormones that play important roles in multiple biological processes. In this paper, a classic rice mutant gsor300084,showing erect leaves and semi-dwarf stature, was characterized. Morphological analysis in darkness showed that the mesocotyl of the gsor300084 mutant did not elongate when grown in darkness. Coleoptile elongation and root growth were less affected by the exogenous application of brassinolide(BL), the most active form of BR, in gsor300084 than in the wild-type rice variety Matsumae. Lamina joint bending analysis also showed that gsor300084 was less sensitive to exogenous BL than Matsumae. These results suggested that the gsor300084 mutant is defective in BR sensitivity. Map-based cloning indicated that gsor300084 is a novel allelic mutant of the DWARF61(D61) gene, which encodes the putative BR receptor OsBRI1. A single-base mutation appears in the LRR domain of OsBRI1, changing the 444 th amino acid from tryptophan(W) to arginine(R). Subcellular localization analysis suggested that both the wild-type and mutant OsBRI1 protein are localized at the cytoplasmic membrane. Structure modeling revealed that the W444 R substitution may affect the perception of BRs by the LRR domain.展开更多
Leaf angle is a major agronomic trait that determines plant architecture,which directly affects rice planting density,photosynthetic efficiency,and yield.The plant phytohormones brassinosteroids(BRs)and the MAPK signa...Leaf angle is a major agronomic trait that determines plant architecture,which directly affects rice planting density,photosynthetic efficiency,and yield.The plant phytohormones brassinosteroids(BRs)and the MAPK signaling cascade are known to play crucial roles in regulating leaf angle,but the underlying molecular mechanisms are not fully understood.Here,we report a rice WRKY family transcription factor gene,OsWRKY72,which positively regulates leaf angle by affecting lamina joint development and BR signaling.Phenotypic analysis showed that oswrky72 mutants have smaller leaf angles and exhibit insensitivity to exogenous BRs,whereas OsWRKY72 overexpression lines show enlarged leaf angles and are hypersensitive to exogenous BRs.Histological sections revealed that the change in leaf inclination is due to asymmetric cell proliferation and growth at the lamina joint.Further investigation showed that OsWRKY72 binds directly to the promoter region of BR receptor kinase(OsBRI1),a key gene in theBR signaling pathway,and activates its expression to positively regulate rice BR signaling.In addition,we discovered that OsWRKY72 interacts with and is phosphorylated by OsMAPK6,and this phosphorylation event can enhanceOsWRKY72 activity in promoting OsBRI1 expression.Genetic evidence confirmed that OsMAPK6,OsWRKY72,and OsBRI1 function in a common pathway to regulate leaf angle.Collectively,our findings clarify the critical role of the OsWRKY72 transcription factor in regulating rice leaf angle.These results provide valuable insights into the molecular regulatory networks that govern plant architecture in rice.展开更多
基金supported by the Special Funding for the Construction of the High-Level Academy of Agricultural Sciences, Guangdong Province, China (NYQS202606)the National Natural Science Foundation of China (32372066 and 32300454)+2 种基金the Guangdong Basic and Applied Basic Research Foundation, China (2023A1515012075 and 2024A1515013064)the Guangzhou Science and Technology Programme, China (2024B03J1363)the Guangdong Academy of Agricultural Sciences, China (R2021YJ-QG005, R2021YJ-YB3011 and R2022PY-QY011)。
文摘Brassinosteroids(BRs) are essential phytohormones that shape rice architecture,grain development,and stress resilience by modulating leaf angle,stem elongation,tillering,and spikelet growth,all of which collectively influence light interception and yield formation(Manghwar et al.2022;Yuan et al.2022;Hou et al.2025;Li et al.2025).Although partial manipulation of BR signaling has recently gained attention as a strategy for ideotype breeding,the translation of BR biology into crop improvement remains hindered by an incomplete understanding of how BR responsiveness varies among elite japonica backgrounds.In this study,we uncovered pronounced differences in BR morphological responsiveness and transcriptional feedback between two widely used japonica cultivars,Taichung 65(TC65) and Zhonghua 11(ZH11),indicating that genetic background has substantial impacts on BR perception and signaling efficiency.Motivated by this finding,we developed a non-transgenic near-isogenic BR-insensitive line,d61-zh11,by introgressing the classical weak OsBRI1 allele(d61-1) from TC65 into the modern,genome-enabled ZH11 background.
基金supported by grants from the Ministry of Science and Technology of China(Grant No.2013CBA01401)the Ministry of Agriculture of China(Grant No.2011ZX08009-003)the Agricultural Science and Technology Innovation Program of China
文摘Brassinosteroids(BRs) are a class of plant-specific steroidal hormones that play important roles in multiple biological processes. In this paper, a classic rice mutant gsor300084,showing erect leaves and semi-dwarf stature, was characterized. Morphological analysis in darkness showed that the mesocotyl of the gsor300084 mutant did not elongate when grown in darkness. Coleoptile elongation and root growth were less affected by the exogenous application of brassinolide(BL), the most active form of BR, in gsor300084 than in the wild-type rice variety Matsumae. Lamina joint bending analysis also showed that gsor300084 was less sensitive to exogenous BL than Matsumae. These results suggested that the gsor300084 mutant is defective in BR sensitivity. Map-based cloning indicated that gsor300084 is a novel allelic mutant of the DWARF61(D61) gene, which encodes the putative BR receptor OsBRI1. A single-base mutation appears in the LRR domain of OsBRI1, changing the 444 th amino acid from tryptophan(W) to arginine(R). Subcellular localization analysis suggested that both the wild-type and mutant OsBRI1 protein are localized at the cytoplasmic membrane. Structure modeling revealed that the W444 R substitution may affect the perception of BRs by the LRR domain.
基金supported by the National Rice Industry Technology Sys-tem of Modern Agriculture for China(grant no.CARS-01-08)the"5511"Collaborative Innovation Project for High-quality Development and Sur-passes of Agriculture between Government of Fujian and Chinese Acad-emy of Agricultural Sciences(grant no.XTCXGC2021001)+4 种基金the Key Pro-gram of Science and Technology in Fujian province,China(grant no.2020NZ08016)the Special Foundation of Non-Profit Research Institutes of Fujian Province(grant no.2020R1023008)the National Natural Science Foundation of China-Youth Science Fund Project(grant no.32201733)the Scientific Research Project of Fujian Academy of Agricultural Sciences(grant no.GJYS202301)the Central Government Guides Local Science and Technology Development Special Project(grant no.2022L3018).
文摘Leaf angle is a major agronomic trait that determines plant architecture,which directly affects rice planting density,photosynthetic efficiency,and yield.The plant phytohormones brassinosteroids(BRs)and the MAPK signaling cascade are known to play crucial roles in regulating leaf angle,but the underlying molecular mechanisms are not fully understood.Here,we report a rice WRKY family transcription factor gene,OsWRKY72,which positively regulates leaf angle by affecting lamina joint development and BR signaling.Phenotypic analysis showed that oswrky72 mutants have smaller leaf angles and exhibit insensitivity to exogenous BRs,whereas OsWRKY72 overexpression lines show enlarged leaf angles and are hypersensitive to exogenous BRs.Histological sections revealed that the change in leaf inclination is due to asymmetric cell proliferation and growth at the lamina joint.Further investigation showed that OsWRKY72 binds directly to the promoter region of BR receptor kinase(OsBRI1),a key gene in theBR signaling pathway,and activates its expression to positively regulate rice BR signaling.In addition,we discovered that OsWRKY72 interacts with and is phosphorylated by OsMAPK6,and this phosphorylation event can enhanceOsWRKY72 activity in promoting OsBRI1 expression.Genetic evidence confirmed that OsMAPK6,OsWRKY72,and OsBRI1 function in a common pathway to regulate leaf angle.Collectively,our findings clarify the critical role of the OsWRKY72 transcription factor in regulating rice leaf angle.These results provide valuable insights into the molecular regulatory networks that govern plant architecture in rice.
