西瓜果皮色泽相关基因的筛选、分离及克隆

In this study, we will screen related candidate genes of skin color(cDNA fragment), using suppression subtractive hybridization(SSH) and cDNA chip technology, with yellow skin mutant and green skin wild of watermelon materials as research object, screening related candidate genes of skin color(cDNA fragment), compare the mRNA differential expression between the materials of wild and mutant, and analysis of differential genes expression on the process of skin color changes. Using Northern Hybridization to research the express characterization on the process of skin color changes and different tissues and organs based on the skin color related cDNA which have been sequenced, and seek the direct evidence that differential genes expression have related with skin color. Isolation the related key genes of skin color, testing those key genes with RNAi technology, To explore the molecular mechanism of skin color. The research will lay the foundation for genetic control of watermelon and molecular breeding research.

本研究利用抑制消减杂交技术（SSH）和cDNA芯片技术，以西瓜黄皮突变型材料、绿皮野生型材料为研究对象，筛选果皮色泽相关的候选基因（cDNA片段）， 比较野生型和突变体材料的mRNA表达差异；并进行果皮色泽变化过程基因差异表达分析。利用Northern杂交技术研究已测序的果皮色泽相关cDNA片段在果皮色泽变化过程和不同组织器官中的表达特性，寻求基因差异表达与果皮色泽相关的直接证据。分离果皮色泽相关的关键基因并采用RNAi技术验证这些关键基因，探索果皮色泽的分子机制。为西瓜果皮色泽的遗传控制、分子育种研究奠定基础。

本研究利用抑制消减杂交技术（SSH）和cDNA芯片技术，以西瓜黄皮突变型材料、绿皮野生型材料为研究对象，获得2个与西瓜果皮色泽相关的cDNA片段，用RACE技术成功扩增Watermelon M457、Watermelon W443基因全长，再经Northern杂交结果表明，只有Watermelon M457呈阳性，Watermelon M457是一个西瓜果皮色泽相关的基因。且用RNAi技术验证了Watermelon M457是一个与西瓜果皮色泽相关的基因。Watermelon M457是一新基因（BLAST比对发现，由于该基因无同源序列可以比较），Watermelon M457转录表达只在突变体材料的果皮部。