恶疫霉侵染的草莓SSH文库的构建及分析

Construction and analysis of SSH library of strawberry crown upon infection with Phytophthora cactorum

为了解草莓与恶疫霉[Phytophthora cactorum(Lebert&Cohn)J.Schrt]互作的分子机制,以感病草莓品种FDP821为材料,以接种恶疫霉的草莓冠部为处理、未接种健康生长的草莓冠部为对照,利用抑制性差减杂交技术构建恶疫霉侵染诱导的草莓差异表达的cDNA差减文库。PCR鉴定随机挑取的阳性克隆,显示插入片段大小为300～1 000bp。随机挑取109个克隆进行测序,获得92个草莓EST,分析表明来自50个草莓基因。BLASTX比对结果表明:这些草莓基因的功能涉及抗病防卫机制、抗氧化作用、物质代谢和蛋白质合成等。这为理解草莓冠腐病抗性分子机制奠定了重要的数据基础。

Strawberry crown rot caused by Phytophthora cactorum is one of destructive diseases endangering strawberry production worldwide.To explore the molecular mechanisms underlying the interaction of strawberry with P.cactorum,a susceptible strawberry variety FDP821 to P.cactorum was used as main material in the study.With mRNA from strawberry crowns infected by P.cactorum as the tester and mRNA from the control crowns as the driver,a subtracted cDNA library of FDP821 was constructed using suppression subtractive hybridization.Colony PCR on randomly picked clones showed that the inserts were between 300-1 000 bp.One hundred and nine clones were sequenced and ninety-two were identified as strawberry expressed sequence tags,representing 50 strawberry genes.BLASTX analysis demonstrated that these genes were involved in disease resistance,antioxidative stress,metabolism and protein synthesis.This study provides a data basis for understanding the molecular mechanisms of strawberry resistance to crown rot caused by P.cactorum.