羊草乙醛脱氢酶（ALDH）基因片段的克隆及表达分析

[研究目的]克隆羊草的乙醛脱氢酶ALDH基因片段，研究该基因在不同条件下的表达情况。[方法]采用RT-PCR技术克隆羊草的ALDH基因片段，并对其核苷酸和氨基酸序列进行分析，采用Real Time RT-PCR 方法研究该基因的表达。[结果]获得了羊草的ALDH基因片段，长度为675 bp，编码225aa。核苷酸序列比较表明，与水稻ALDH1a序列(AB037421)同源性为86%，与玉米RF2C（AF348413）同源性为85%。BLASTp分析，该序列与水稻、玉米、拟南芥的乙醛脱氢酶一致性分别高达87%、86%、60%，含有醛脱氢酶基因家族的保守结构域。Real Time RT-PCR数据表明，在诱导条件下该基因的表达量呈先升高后降低的趋势。总体上来说，该基因对盐的响应要高于干旱和冷冻。[结论]本研究成功获得了羊草ALDH基因片段，并研究了该基因的表达情况，为进一步克隆羊草ALDH全长基因奠定了基础。

Molecular Cloning and Expression Analysis of Aldehyde Dehydrogenase (ALDH) Gene Segment in Leymus Chinensis

[Objective]Aldehyde Dehydrogenase (ALDH) gene segment from Leymus Chinensis was cloned and the expression of it was researched under the different situations.[Method]ALDH gene segment was cloned by RT-PCR. The nucleotide and amino acid sequence of ALDH were analyzed. The expression of ALDH was researched by Real Time RT-PCR.[Result]ALDH gene segment was obtained which was 675bp and coding 225aa. The compare of nucleotide sequences indicated that it has 86% identity with rice ALDH1a (AB037421), and 85% identity with maize RF2C(AF348413). By BLASTp Analysis, it shares 87%, 86% and 60% amino acid sequence identity with rice, maize and Arabidopsis thaliana ALDH, respectively, which containing conservation region of aldehyde dehydrogenase families. The data of Real Time RT-PCR indicated that the expression of ALDH was increased first, and then decreased under the inducing situations. As a whole, the responses of ALDH to salt and drought were much higher than to cold.[Conclusion]In this research, ALDH gene segment was obtained, and we researched the expression of ALDH. It established basis on cloning the span of ALDH in Leymus Chinensis.