水稻圆粒基因RS的鉴定和定位

Identification and mapping of round seed related gene in rice (Oryza sativa L.)

阐明水稻籽粒大小相关基因的遗传和分子机制对水稻产量形成具有重要意义。利用甲基磺酸乙酯(ethyl methanesulfonate, EMS)诱变粳稻品种"宁粳3号"筛选获得圆粒突变体round seed (rs)。遗传分析表明,突变体rs圆粒表型由单隐性核基因控制。颖壳扫描电镜观察发现,rs籽粒变圆主要是细胞数目改变导致的。在突变体rs中,细胞周期相关基因的表达较野生型显著升高。将RS定位在第3染色体短臂标记RM3413与N3-5之间,物理距离约589 kb。RS突变影响BR信号途径,改变了粒型相关基因的表达。本研究有助于阐明水稻籽粒发育的分子机制。

It is significant to clarify the genetic and molecular mechanism of genes related to rice grain size for rice yield.A mutant round seed(rs)was screened from japonica variety“Ningjing3”mutagenized by ethyl methane sulfonate(EMS).Genetic analysis revealed that the phenotype of rs was controlled by a single recessive nuclear gene.Scanning electron microscope observation indicated that the change of cell number was responsible for the mutant phenotype of rs.Compared with the wild type,the expression of cell cycle related-genes increased significantly in rs.RS was located in the589kb region of chromosome3,between markers RM3413and N3-5.The RS mutation affected BR signal pathway,and changed the expression of grain size-related genes.This research contributes to elucidating the molecular mechanism of rice grain development.