黑龙江省4个主栽水稻品种GS3基因克隆及表达模式分析

Cloning and Expression Analysis of GS3 in Four Main Rice Varieties from Hei⁃longjiang Province

GS3是克隆的第一个负调控水稻粒长和粒重的基因。本研究在黑龙江省4个主栽水稻品种龙粳31、绥粳18、龙稻18和龙稻21中克隆GS3基因编码区并进行序列分析,发现4个品种的GS3基因都存在可变剪切,共检测到5种剪切类型。根据编码蛋白序列预测,有3种剪切类型是有功能类型。实时定量PCR检测结果表明,4个品种GS3基因均以有功能的剪切类型为主,在穗发育过程中表达呈现逐渐降低的趋势,长粒品种幼穗中表达量低于圆粒品种。本试验结果表明,这4个品种中GS3基因在穗发育过程中对粒长起负调控作用,可作为遗传操作靶位点进行粒形改良。

GS3 is the first cloned gene that negatively regulates grain length and grain weight in rice.In this study,the coding region of GS3 in four main rice varieties(Longjing 31,Suijing 18,Longdao 18 and Longdao 21)from Hei⁃longjiang Province was cloned and sequenced.Alternative splicing of GS3 was detected in each of the four varieties and a total of five splicing patterns were identified,three of which were recognized as functional according to the amino acid sequence analysis on their coding protein.As was shown in real-time quantitative PCR results,func⁃tional splicing types were the most abundant splicing patterns dominant in the four varieties and their expression de⁃creased gradually during the panicle development.The expression varied significantly among the four varieties.GS3 expression level in long-seed varieties was lower than that in short-seed varieties.It was concluded that GS3 gene played vital roles in negative regulating seed length during panicle development in the four varieties,which could be used as the target gene for genetic operation to improve grain shape.