陆地棉光合系统ⅡPsbR基因的克隆和表达分析

Cloning and Expression Analysis of Photosystem Ⅱ PsbR Gene in Gossypium hirsupum

以拟南芥光合系统Ⅱ PsbR蛋白序列为探针,通过电子克隆的方法得到陆地棉光合系统Ⅱ PsbR基因的cDNA序列,进行序列分析,并对其在棉花不同组织中的表达水平进行研究。结果表明:克隆得到1条699bp的棉花PsbR基因cDNA序列,预测其ORF长为420bp,编码139个氨基酸,蛋白分子质量为14.26ku;多序列比对结果显示,棉花PsbR蛋白与牧豆树、马铃薯等具有较高的相似性,与芜菁、菠菜等的相似率较低;在进化关系上,棉花PsbR蛋白与葡萄、蓖麻、杨树等亲缘关系较近,与黄瓜、芜菁、烟草等进化关系较远;定量结果说明,PsbR基因在棉花不同组织中均有表达,但表达水平不同,在叶片中表达量最高。

A 699 bp cotton（Gossypium hirsupum）PsbRcDNA was cloned by means of in silico cloning,using Arabidopsis thaliana PsbR protein sequence as a probe.Then the sequence was analyzed,and the expression level in different tissues of cotton was studied.It was predicted that the GhPsbR gene has an ORF of 420 bp,encoding a 14.26 ku protein of 139 amino acids.Multiple alignment showed that the GhPsbRprotein has higher similarity with that of Prosopis julifloraand Solanum tuberosum,lower similarity with that of Brassica rapaand Spinacia oleracea.Phylogenetic tree of different species reflected that it has a higher homology with that of Vitis vinifera,Ricinus comunis,Populus trichocarpa et al.,and lower homology with that of Cucumis sativus,Brassica rapa,Nicotiana thaliana et al.Real-time quantitative analysis suggested that the PsbRgene can be detected in each tissue but the expression level varied from tissues,and it was higher in leaves and stems than that of other tissues.