Cloning and expression analysis of a glucosyltransferase gene gh3gt from natural brown cotton fiber | 天然棕色棉葡萄糖苷转移酶基因Gh3GT的克隆与表达分析

صينى. 本研究以发育18d的天然棕色棉及相同发育时期的白色棉近等基因系纤维细胞为材料,采用抑制性差减杂交结合RACE技术分离得到了一个葡萄糖苷转移酶基因的全长cDNA,命名为Gh3GT（GenBank登录号eu921265）。序列分析发现：该基因编码一条有450个氨基酸残基组成的多肽,含有葡萄糖苷转移酶C-端所特有的保守的信号序列PSPG基序,属于植物中特有PSPG基序的UGT家族成员。推断的Gh3GT编码产物与其它糖苷转移酶同源性比对和系统发生分析表明：该糖苷转移酶与玫瑰Rh3GT（Rosa hybrida）、矮牵牛（Petunia hybrida）PhF3GT以及葡萄VvUFGT（Vitis vinifera）的相似性分别为51.30%、46.94%和45.85%,而与已知的陆地棉糖苷转移酶基因GhUGT1和GhUGT2一致性较低,仅为25.37%和12.14%。半定量RT-PCR分析表明：该基因在棕色棉纤维中的表达量明显高于其它组织及其近等基因系白色棉品种,且其在纤维中的表达规律与棕色棉的色素形成过程一致。[著者文摘]

إنجليزي. In this study,we used the fibrocyte of natural brown cotton fiber and white cotton fiber near-isogenic lines which both were 18 d post anthesis as test materials,the full length cDNA sequence of one glucosyltransferase gene was cloned by SSH（suppression subtractive hybridization） combined together RACE（rapid amplification of cDNA ends）,and was named as Gh3GT（GenBank accession No.eu921265）.Sequence analysis revealed that it encodes a protein with 450 amino acids,containing typical plant glucosyltransferase characteristic signal motif including PSPG（putative secondary plant glucosyltransferase）,is a member of UGT family.Sequence alignment of Gh3GT with other known glucosyltransferases revealed that Gh3GT shared 51.30%、46.94% 、45.85% identity with Rh3GT from Rosa hybrida,PhF3GT from Petunia hybrida,and VvUFGT from Vitis vinifera,while it shared very low identity with GhUGT1 and GhUGT2 from cotton fiber（Gossypium hirsutum）,25.37% and 12.14%,respectively.Semi-quantitative RT-PCR analysis revealed that the expression of Gh3GT is much higher in brown cotton fiber than in other tissues and in white cotton fiber,and the gene expression coincided with pigment formation in brown cotton fiber.[著者文摘]