马铃薯StRac5、StRac7和StRac13基因的克隆及其表达模式分析

Cloning and Expression Patterns of StRac5 , StRac7 and StRac13 Genes in Potato

探究马铃薯基因的表达模式,为后续研究基因对马铃薯病害的抗性影响提供理论依据。以马铃薯为试验材料,克隆获得3个马铃薯内源小G蛋白基因StRac5、StRac7、StRac13,并对其进行生物信息学分析和表达模式分析。结果表明,StRac5、StRac7、StRac13与拟南芥和水稻中的小G蛋白含有相似的保守序列,均属于ROP蛋白。StRac5和StRac13的蛋白结构域与拟南芥AtRop1、AtRop3、AtRop5、AtRop6及水稻OsRac5、OsRac6、OsRac7相同,StRac7与拟南芥AtRop9的蛋白结构域相同。系统进化树分析表明,StRac7属于第Ⅱ类,与拟南芥AtRop9遗传距离最近;StRac13属于第Ⅲ类,与拟南芥AtRop7遗传距离最近;StRac5属于第Ⅳ类,与水稻OsRac5和OsRac6遗传距离最近。在马铃薯不同组织中,StRac5、StRac7、StRac13基因的相对表达量均为叶>根>茎;与其在茎中表达量比较,StRac5、StRac7和StRac13在叶中的表达量分别增加了1222.4%,2531.3%,468.2%;接种晚疫菌后,StRac5、StRac7和StRac13基因的相对表达量均出现先升高后降低的趋势,StRac5和StRac13基因的相对表达量在接菌24 h后较0 h分别上调了62.2%,40.4%,StRac7基因的相对表达量在接菌72 h后较0 h上调了827.8%;经过ABA、SA、GA和6-BA处理后,StRac5、StRac7、StRac13基因的相对表达量呈现下调的趋势;JA和IAA处理后,StRac5、StRac7、StRac13基因的相对表达量呈现上调的趋势。因此,StRac5、StRac7和StRac13基因能够响应马铃薯晚疫病的侵染,在不同组织和不同激素处理下表达模式也存在一定差异。

To explore the expression patterns of potato genes and provide theoretical basis for the subsequent study of gene resistance to potato diseases.Three endogenous small G protein genes StRac5,StRac7 and StRac13 were cloned from potato,and their bioinformatics and expression patterns were analyzed.The results showed that StRac5,StRac7 and StRac13 contained similar conserved sequences to the small G proteins in Arabidopsis and rice,all belonging to ROP proteins.The protein domains of StRac5 and StRac13 were identical with AtRop1,AtRop3,AtRop5,AtRop6 of Arabidopsis and rice OsRac5,OsRac6,OsRac7,and StRac7 was identical with AtRop9.Phylogenetic tree analysis showed that StRac7 belonged to classⅡand was closest to Arabidopsis AtRop9.StRac13 belonged to classⅢand was the closest genetic relative to Arabidopsis AtRop7.StRac5 belonged to class IV and was the closest genetic relative to rice OsRac5 and OsRac6.The relative expression levels of StRac5,StRac7 and StRac13 genes in different tissues of potato were leaf>root>stem.Compared with the expression in stems,the expression of StRac5,StRac7 and StRac13 in leaves were increased by 1222.4%,2531.3%and 468.2%,respectively.After inoculation,the relative expression of StRac5,StRac7 and StRac13 genes increased first and then decreased,and the relative expression of StRac5 and StRac13 genes increased by 62.2%,40.4%,respectively,compared with 0 h after inoculation 24 h.The relative expression of StRac7 gene was increased by 827.8%at 72 h after inoculation compared with 0 h.After ABA,SA,GA and 6-BA treatment,the relative expression of StRac5,StRac 7 and StRac13 genes showed a downward trend.After JA and IAA treatment,the relative expression of StRac5,StRac7 and StRac13 genes showed an up-regulated trend.Therefore,StRac5,StRac7 and StRac13 genes can respond to potato late blight infection,and their expression patterns are different in different tissues and under different hormone treatments.