莲瓣王捧瓣与舌瓣SSH文库构建及EST序列分析

Construction of SSH cDNA Library and the Corresponding EST Analysis in Petals and Labellum of Cymbidium lianpan

为了探索兰花舌瓣形成的分子机制,本研究利用消减抑制杂交技术构建了莲瓣王(Cymbidium lianpanTang et Wang)捧瓣与舌瓣间的cDNA文库。对正向文库中随机挑选的147个阳性克隆测序,组装、拼接,找到37个唯一序列,其中包含25个单一序列和12个拼接序列。经同源性比对,这些EST分别归类于蛋白质折叠,结合、未知功能、应激反应、光合作用、转录调控、信号传导、生物合成、新陈代谢、MADS等10类。通过对MADS-box基因的系统进化树分析,可初步推测MADS-Contig1和MADS-Contig2属于A类基因中的SQUA-like亚家族基因。

In order to explore the molecular mechanism of orchid labellum formation, the suppression subtractive hybridization （SSH） cDNA library was constructed with petals and labellum of Cymbidium lianpart in this study. One hundred and forty-seven randomly selected clones of positive library were sequenced, assembled and spliced, 37 unique sequences were found, containing 25 single sequences and 12 spliced sequences. After ho- mology comparison, these ESTs were classified as protein folding, binding, unknown function, stress response, photosynthesis, transcription regulation, signal transduction, biosynthesis, metabolism, MADS and other 10 cat- egories. Through the analysis of phylogenetic tree about MADS-box genes, we can initially speculate that MADS- Contigl and MADS-Contig2 belong to A class SQUA-like subfamily genes.