摘要： 为了研究马铃薯内源BAG基因在晚疫病抗性建立中的作用，利用拟南芥和水稻的BAG基因保守序列，在马铃薯基因库中比对获得马铃薯内源StBAG3的基因序列。以StBAG3基因序列为模板设计引物，通过RT-PCR克隆得到了StBAG3基因cDNA序列。序列分析的结果表明，该基因开放阅读框为1 026 bp，编码341个氨基酸。蛋白二级结构预测结果表明，StBAG3具有UBQ和BAG 2个保守功能域。StBAG3基因的表达谱分析结果显示，不同马铃薯品种中StBAG3基因表达水平存在差异，其中在冀张薯12号中表达量最高，而夏坡蒂中表达量最低。该基因在马铃薯不同组织中表达量测定结果表明，马铃薯茎中的表达水平最高，老叶中表达水平最低。接种晚疫菌后，StBAG3能够被显著上调并在接种48 h后达到最高值，预示着StBAG3基因在马铃薯晚疫病抗性建立过程中具有一定的调控作用。

关键词: 马铃薯, StBAG3, 基因克隆, 晚疫菌, 表达

Abstract: In order to study the functions of StBAG3 during the establishment of potato resistance to Phytophthora infestans (P.infesans),endogenous StBAG3 gene was cloned from potato through PCR with primers devised based on the conserved sequence of BAG cloned from Arabidopsis and rice.The sequence analysis results showed the open reading frame of StBAG3 gene was 1 026 bp and encodes 341 amino acids.The protein secondary structure prediction indicated that the StBAG3 contains two conserved domains,UBQ and BAG.The expression level of StBAG3 gene in different potato cultivars was variable and Jizhanghsu 12 showed the highest level,whereas,the expression level in Shepody was the lowest one.Also,the expression profile in different tissues of potato was also variable,and it showed highest in stem,but,the lowest in the old leaves.After inoculation with P.infestans, th e StBAG3 gene expression was significantly induced and reached to the highest level at 48 h,indicating StBAG3 is involved in the establishment of potato resistance against potato late blight.

Key words: Potato, StBAG3, Gene clone, P.infestans, Expression

中图分类号: 

• Q812

• Q87