摘要： 为了比较分析OsRSR1表达特点及序列和功能变异与性状遗传变异关系，选用籽粒直链淀粉含量很高的籼稻品种和极低的糯稻品种及遗传背景相似，但籽粒直链淀粉含量存在显著差异的粳稻亲本和杂交子代超亲变异系等为供试材料，进行转录因子基因OsRSR1的克隆、表达量测定及生物信息学分析。结果表明，灌浆初始阶段和后期阶段OsRSR1表达量大，灌浆中期表达量小，呈V字形变化，籽粒OsRSR1表达量高的品种其籽粒直链淀粉含量低，反之表达量低的品种籽粒直链淀粉含量高，二者间呈负相关关系，而且品种间有性杂交子代OsRSR1表达量会出现超亲变异；籽粒直链淀粉含量不同的水稻品种间OsRSR1全长DNA碱基序列及mRNA碱基序列和氨基酸序列并不完全一致，存在着多态性，与亲本相比有性杂交后代DNA碱基序列无论是在外显子区还是内含子区都可发生变化，而且DNA转录mRNA过程中也发生个别碱基的变化，形成与DNA碱基序列不配的mRNA碱基序列，最终形成同义或非同义的三联体密码，是性状产生遗传变异和基因多态性的重要途径；OsRSR1由8个外显子和7个内含子组成，基因序列的碱基变化均未改变基因的完整结构，籽粒直链淀粉含量差异显著的6个供试材料间的个别氨基酸差异并未导致OsRSR1蛋白的基本元件和功能变化，该蛋白结构域保守性很强。为深入研究基因转录水平的分子调控和遗传变异机制提供理论依据。

关键词: 水稻, 超亲变异系, OsRSR1基因序列, 表达特性, 遗传变异

Abstract: In order to compare and analyze the relationship between OsRSR1 expression,sequence and functional variation and trait genetic variation. Indica rice varieties with high amylose content(AC),glutinous rice varieties with very low AC,Japonica parents and hybrid progenies with similar genetic background and significantly different amylose content were used in this study. Cloning,expression assay and bioinformatics analysis of transcription factor gene OsRSR1 were carried out. The results showed that OsRSR1 expression level was high at the initial and late stage of grain filling,but low in the middle stage,like a V-shape. OsRSR1 expression level was high in varieties with low AC,vice versa in varieties with high AC. It indicated the negative relationship between OsRSR1 expression and grain AC,and transgressive variation in hybrid progenies. DNA sequence,transcript and protein sequence of OsRSR1 were not identical. DNA base changes were detected in exons and introns of sexual hybrid progenies,and single base substitution(SBS)occurred in transcript to produce code variation,this was an important approach to genetic variation and gene polymorphism. OsRSR1 is composed of eight exons and seven introns. The changes of SBS and amino acid did not alter OsRSR1 gene structure and relative motif as well as function,which implied AP2 domains was highly conserved. The results would be helpful for further study on the molecular regulation of gene transcriptional level and genetic variation mechanism.

Key words: Rice, Transgressive variant, OsRSR1 gene sequence, Expression characteristics, Genetic variation

中图分类号: 

• Q78

• S511.03