Genetic analysis and gene cloning of a triangular hull 1 (tri1) mutant in rice (Oryza sativa L.)  

作　　者：FENG GongNeng ZHANG ChangQuan TANG MingYong ZHANG GuiYun XU ChenWu GU MingHong LIU QiaoQuan 

机构地区：[1]Key Laboratory of Plant Functional Genomics of Ministry of Education/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, Yangzhou University [2]Yancheng Institute of Technology

出　　处：《Chinese Science Bulletin》2013年第24期2984-2991,共8页

基　　金：supported by the National Key Basic Research and Development Project (2012CB944803);the National Natural Science Foundation of China (31071383);the Funds for Distinguished Young Scientists of Jiangsu Province (BK2012010);Priority Academic Program Development from Jiangsu Government, China

摘　　要：Grain shape and size are two key factors that determine rice yield and quality. In the present study, a rice triangular hull mutant (tri1) was obtained from the progeny of japonica rice variety Taipei 309 treated with 60Co γ-rays. Compared to the wild type, the tri1 mutant presents a triangular hull, and exhibits an increase in grain thickness and protein content, but with a slight decrease in plant height and grain weight. Genetic analysis indicated that the mutant phenotype was controlled by a recessive nuclear gene which is stably inherited. Using a map-based cloning strategy, we fine-mapped tri1 to a 47-kb region between the molecular markers CHR0122 and CHR0127 on the long arm of chromosome 1, and showed that it co-segregates with the molecular marker CHR0119. According to the rice genome sequence annotation there are six predicated genes within the mapped region. Sequencing analysis of the mutant and the wild type indicated that there was a deletion of an A nucleotide in exon 3 of the OsMADS32 gene, which could result in a downstream frameshift mutation and premature termination of the predicted polypeptide. Both semi-quantitative and real-time RT-PCR analyses showed that this gene expressed highly in young inflorescences, while expressed at very low levels in other tissues. These results implied that the OsMADS32 gene could be a candidate of TRI1. Taken together, the results of this study lay the foundation for further investigation into the molecular mechanisms regulating rice caryopsis development.Grain shape and size are two key factors that determine rice yield and quality. In the present study, a rice triangular hull mutant （tril） was obtained from the progeny of japonica rice variety Taipei 309 treated with 60Co y-rays. Compared to the wild type, the tril mutant presents a triangular hull, and exhibits an increase in grain thickness and protein content, but with a slight decrease in plant height and grain weight. Genetic analysis indicated that the mutant phenotype was controlled by a recessive nuclear gene which is stably inherited. Using a map-based cloning strategy, we fine-mapped tril to a 47-kb region between the molecular markers CHR0122 and CHR0127 on the long arm of chromosome 1, and showed that it co-segregates with the molecular marker CHR0119. According to the rice genome sequence annotation there are six predicated genes within the mapped region. Sequenc- ing analysis of the mutant and the wild type indicated that there was a deletion of an A nucleotide in exon 3 of the OsMADS32 gene, which could result in a downstream frameshift mutation and premature termination of the predicted polypeptide. Both semi-quantitative and real-time RT-PCR analyses showed that this gene expressed highly in young inflorescences, while ex- pressed at very low levels in other tissues. These results implied that the OsMADS32 gene could be a candidate of TRll. Taken together, the results of this study lay the foundation for further investigation into the molecular mechanisms regulating rice cary- opsis development.

关 键 词：隐性核基因 水稻产量 遗传分析 克隆策略 突变体 三角形 船体 RT-PCR分析 

分 类 号：S511[农业科学—作物学]