从转录组和表观遗传角度探讨嫁接提高黄瓜耐冷性的分子机制

项目名称： 从转录组和表观遗传角度探讨嫁接提高黄瓜耐冷性的分子机制

项目编号： No.31201616

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 植物保护学、园艺学与植物营养学

项目作者： 叶雪凌

作者单位： 沈阳农业大学

项目金额： 25万元

中文摘要： 黄瓜为典型的冷敏蔬菜作物，嫁接可有效提高其耐冷性。目前，嫁接提高黄瓜耐冷性的分子机制尚不明了。本项目以耐冷性强的黑籽南瓜和冷敏黄瓜高代自交系为试材，利用Illumina测序技术，对常温和冷胁迫下嫁接苗和自根苗叶片的转录组、microRNA表达谱进行平行检测，分别鉴别出存在明显表达差异的RNA和microRNA，通过对以上基因的功能注释、gene ontology分析，找到统计学上最有意义的代谢途径，为从单一代谢途径研究嫁接黄瓜的耐冷性奠定基础；同时，利用甲基化DNA 免疫共沉淀测序技术（MeDIP-seq）绘制常温和冷胁迫下嫁接苗和自根苗叶片的全基因组甲基化图谱，捕获存在差异的DNA甲基化位点，结合以上的mRNA和microRNA测序结果，从转录组和表观遗传角度协同探讨嫁接提高黄瓜耐冷性的分子机制。本项目可为植物抗逆性研究提供一个新的思路，研究成果对于深入探讨植物耐冷分子机制具有重要意义。

中文关键词： 黄瓜；嫁接；耐冷性；分子机制；

英文摘要： Cucumber(Cucumis sativus L.) is a typical chilling-sensitive vegetable crop. Grafting can improve the chilling tollerance of cucumber obviously, but the molecular mechanisms still remains to be clarified. In this study, chilling-tolerant cucurbita ficifolia and a chilling-sensitive inbred line of cucumber will be used as test materials. Illumina platform-based RNA-seq and small RNA-seq will be performed to analyze the transcriptome and microRNA expression profile of leaves from grafted seedlings and self-grafted cucumber seedlings under ordinary temperature and low temperature(chilling stress), respectively.Differentially expressed mRNA and microRNA will be screened out respectively, and the function annotation and gene ontology analysis will be carried out to find the most meaningful metabolic pathway. This will lay the foundation of the study of chilling tolerance of grafted cucumber from a single metabolic pathway. At the same time, we aim to determined the genome-wide methylation profile of leaves from grafted seedlings and self-grafted seedlings under ordinary temperature and low temperature using methylated DNA co-immunoprecipitation sequencing technology（MeDIP-seq）, to target the DNA methylation sites that have differences. Combined with the sequence consequence of mRNA and microRNA above, this study i

英文关键词： Cucumber；grafting；chilling tolerance；molecular mechanism；