水茄泛素结合酶E2基因StUBCc的克隆及黄萎病菌诱导表达分析

以茄子近缘野生种水茄（Solanum torvum Swartz）幼苗根部为试材，并以黄萎病菌（大丽轮枝菌，Verticillium dahliae Kleb）处理的水茄的抑制差减文库中差异表达的EST片段F290为基础，利用RACE技术，获得一个756 bp的cDNA全长序列。经生物信息学分析发现该序列为泛素结合酶E2-2（UBC2）载体蛋白同源基因，命名为StUBCc，GenBank登录号为KP330492。StUBCc基因编码区共459 bp，编码152个氨基酸，该蛋白分子量为63.0925 kD，等电点为5.13。采用MEGA 5软件对StUBCc和其他同源蛋白的氨基酸序列比对，结果表明其与葡萄的同源蛋白一致性最高，达99%，有很高的功能区段保守性。采用荧光定量PCR对黄萎病菌侵染不同时间的水茄幼苗根部StUBCc基因的表达量进行测定，发现在侵染6 h后，表达量最高，为对照（无菌水处理）的6.79倍。

Cloning and Expression Analysis Induced by Verticillium Wilt Fungus of Ubiquitin-conjugating Enzyme Gene StUBCc from Solanum torvum

An EST F290 was from suppression subtractive hybridization library made from pathogen treated roots of the seedling roots of verticillium wilt（Verticillium dahliae Kleb）resistant Solanum torvum Swartz. A full length cDNA（756 bp）was obtained using rapid amplification of cDNA ends（RACE）technology，which encoded the ubiquitin-conjugating enzyme E2-2（UBC2）family gene and was designated as StUBCc. GenBank number is KP330492. The putative protein contains of 152 amino acids with a molecular weight of 63.0925 kD and a theoretical pI of 5.13. Multiple sequence alignment of the amino acid sequence between StUBCc and other homologs from several plants were analyzed by MEGA 5 and shows that the StUBCc has higher identity with UBC genes from Vitis vinifera. The identities is 99% with a deduced amino acid sequence of highly conserved functional domain. The expressions of the isolated StUBCc in the roots of S. torvum seedlings treated by verticillium wilt fungus as well as sterilewater at different time points was studied by using quantitative RT-PCR. The results indicated that the expression of the newly isolated StUBCc gene was induced by verticillium wilt infection and was 6.79 times more than the comparison at 6 hours post infection.