玉米小G蛋白ZmRab7基因克隆及其盐胁迫响应分析  

Cloning and Salt Stress Response Analysis of ZmRab7 Gene in Zea mays L.

作　　者：牛艳丽 贾明珠 韩栓[1] 付佳苗 刘凌云[1] NIU Yanli;JIA Mingzhu;HAN Shuan;FU Jiamiao;LIU Lingyun(School of Life Sciences,Henan University,Henan Key Laboratory of Plant Stress Biology,Kaifeng 475004,China)

机构地区：[1]河南大学生命科学学院,植物逆境生物学重点实验室,河南开封475004

出　　处：《华北农学报》2020年第3期1-6,共6页Acta Agriculturae Boreali-Sinica

基　　金：河南省自然科学基金项目(162300410008);河南省研究生教育改革与质量提升工程项目(hnyjs2017kc24)。

摘　　要：为探讨小G蛋白在玉米盐胁迫响应中的作用,克隆玉米ZmRab7基因并对其生理功能进行初步分析。生物信息学分析表明,ZmRab7基因编码206个氨基酸,包含保守的G1-G5基序和C末端Cys位点;系统进化分析显示,玉米ZmRab7蛋白与同为单子叶植物的高粱SbRab7亲缘关系最近;ZmRab7蛋白在二级结构和三级结构上由4个α-螺旋和多个β-折叠、无规卷曲组成功能域,且与双子叶植物拟南芥AtRab7空间结构高度相似。进一步研究发现,ZmRab7主要在玉米的根及幼胚中表达;该基因启动子区含有4个GT1GMSCAM4和2个DRECRTCOREAT盐胁迫响应元件,高盐能够轻微抑制其表达;酵母生长试验证实,ZmRab7-pYES2转基因酵母表现出盐胁迫不耐受表型。这些结果说明,玉米ZmRab7基因编码1个响应盐胁迫的Rab类小G蛋白,为进一步详细阐明玉米中Rab类蛋白的生理功能奠定了基础。To study the function of maize small G protein in salt stress,the ZmRab7 was identified and its role was characterized in tolerance to salt stress.Multiple sequence alignment showed that ZmRab7 encoded 206 amino acids,including conserved G1-G5 motifs and C-terminal Cys site.Phylogenetic analysis indicated that the amino acid sequence of ZmRab7 was highly homologous to SbRab7 in Sorghum bicolor.There were fourα-helixes,severalβ-sheets and random coils in the predicted secondary and tertiary structure of ZmRab7,which was similar to the spatial structure of AtRab7.Furthermore,in the promoter region of ZmRab7,there were four GT1GMSCAM4 and two DRECRTCOREAT cis-acting elements to respond to salt stress.ZmRab7 was mainly expressed in the maize root and young embryo,and slightly repressed by high salt treatment.Additionally,heterologous expression of ZmRab7 in yeast remarkably reduced yeast cell tolerance to salt stress.Taken together,these results suggested that ZmRab7 might act as a negative regulator involved in the salt stress response.

关 键 词：玉米 Rab7 小G蛋白 盐胁迫 

分 类 号：Q78[生物学—分子生物学] S513.03[农业科学—作物学]