疫霉侵染下辣椒幼苗消减文库的构建与初步分析

为了分离和鉴定辣椒中疫霉诱导基因，以高抗疫霉病辣椒品种L11为材料，以接种辣椒疫霉菌的幼嫩叶片为处理（tester），以未接种自然生长的幼嫩叶片为对照(driver)，利用抑制性消减杂交技术(suppression subtractive hybridization，SSH)构建了疫霉侵染下辣椒幼苗的消减文库。从消减文库中随机挑取30个阳性克隆，提取质粒进行PCR鉴定，显示插入片段大小大部分集中在200～1 000 bp之间，文库质量良好。随机挑取40个克隆进行测序，共获得35个有效EST序列。经Blastx分析表明：有30个EST与GenBank中其他序列有同源性，5个EST为未知功能序列。已知功能的EST序列分别编码NAC转录因子、丝氨酸/苏氨酸蛋白激酶、P450单加氧酶、叶绿素a/b结合蛋白、谷胱甘肽转移酶、几丁质酶等，这些蛋白涉及抗病信号传递、抗氧化作用、转录调控及光合作用等多种生理过程。本研究为抗病基因克隆和系统研究疫霉侵染下辣椒基因的表达奠定了重要的理论基础。

Construction and Primary Analysis of Subtractive cDNA Library of Capsicum annuum L. Under Phytophthora capsici Stress

To identify the Phytophthora capsici stress induced genes of pepper,a high P.capsici resistant pepper cultivar was used as main material in this study.With cDNA from pepper seedlings treated with P.capsici as the tester and cDNA from this plant in normal growth as the driver,we constructed subtracted library using suppression subtractive hybridization(SSH).Thirty positive clones were picked out randomly from SSH library,plasmid PCR suggested that the inserts were between 200-1 000 bp and library was suitabl...