中国水稻科学2026，Vol.40Issue(5)：584-597,14.DOI:10.16819/j.1001-7216.2026.251212
水稻粒形和穗粒数基因GSN4的克隆与单倍型分析
Cloning and Haplotype Analysis of GSN4,a Gene for Grain Size and Grain Number in Rice
摘要
Abstract
[Objective]Grain size is a critical determinant of rice yield.This study aims to explore novel genes regulating grain size and expand the current genetic regulatory network,and provide valuable genetic resources for molecular design breeding of high-yield rice varieties.[Method]The large-grain mutant gsn4,generated by EMS mutagenesis of the japonica rice variety W7,was used as experimental material.A combination of systematic phenotypic identification,cytological observation,gene mapping,functional verification,subcellular localization,and haplotype analysis was performed to clone and functionally characterize the candidate gene.[Result]Phenotypic identification revealed that the gsn4 mutant exhibited pleiotropic effects.Compared with the wild type,its grain length,grain width,and 1000-grain weight were significantly increased,whereas plant height,panicle length,and grain number per panicle were significantly decreased.Cytological analysis indicated that GSN4 regulates rice grain size by modulating both cell proliferation and expansion in glumes.Map-based cloning,together with CRISPR/Cas9 gene-editing validation,confirmed LOC_Os04g46450 as the candidate gene underlying GSN4.This gene encodes a nuclear-localized E3 ubiquitin ligase protein,which acts as a negative regulator of rice grain size and modulates plant growth and development through the brassinosteroid(BR)biosynthesis pathway.Haplotype analysis further identified Hap1 as the elite haplotype conferring the most favorable effects on grain width and 1000-grain weight.[Conclusion]Collectively,this study elucidates the function and regulatory mechanism of GSN4,enriches the genetic regulatory network governing rice grain size,and provides important genetic resources and a theoretical basis for molecular design breeding of high-yield rice varieties.关键词
粒形/GSN4/细胞周期/细胞扩张/水稻/单倍型/油菜素内酯Key words
grain size/GSN4/cell cycle/cell expansion/rice/haplotype/BR引用本文复制引用
柴炳泽,朱丽,张强,张光恒,钱前,胡江,王俊格,吴凯雄,刘嘉龙,吴越,王荟森,谭霖,任德勇,高振宇..水稻粒形和穗粒数基因GSN4的克隆与单倍型分析[J].中国水稻科学,2026,40(5):584-597,14.基金项目
三亚中国农业科学院国家南繁研究院南繁专项(YBXM2526) （YBXM2526）
国家自然科学基金资助项目(32272109,32188102) （32272109,32188102）
海南省院士创新平台科研项目(YSPTZX202502) （YSPTZX202502）
中国农业科学院农业科技创新计划资助项目(ASTIP,CAAS-ZDRW202401). （ASTIP,CAAS-ZDRW202401）
