低温是影响茶树正常生长和地理分布最重要的限制性环境因素之一。在课题组前期研究工作的基础上，基于高通量测序技术，从低温胁迫条件下mRNA和microRNA(miRNA)两个方面的差异表达着手，构建茶树应答低温胁迫相关基因和miRNA的数字化差异表达谱。通过整合分析miRNA和mRNA表达谱，研究它们在不同胁迫时间、温度、环境下的动态表达规律；并从系统生物学的角度，构建基因、miRNA共表达网络以及miRNA-mRNA调控关系网络，挖掘茶树抗寒、抗冻相关的miRNA及其靶基因和miRNA-mRNA协同作用功能模块，探明茶树响应低温胁迫相关基因间的相互作用及其上游调控网络，进而从转录及转录后水平上初步揭示茶树抗寒、抗冻分子机制；并筛选得到重要的茶树抗寒、抗冻相关分子标记，获得具有自主知识产权的重要功能基因和miRNA，为今后利用分子标记进行茶树育种抗寒性早期鉴定提供理论指导。

Low temperatures are one of the most critical environmental factors that limit its growth, survival and geographical distribution. Based on the previous research of our team, digital differential expression profiles of cold stress responsive genes and miRNAs of tea plant were established using high-throughput sequencing technology. And dynamic expression pattern of miRNA and mRNA expression profiles under different stress time, temperature and environment was studied through the integrated analysis of miRNA and mRNA expression profiling. Then gene and miRNA co-expression network and miRNA-mRNA regulatory networks were established to mine the cold-resistant miRNA and its target genes and miRNA-mRNA synergistic function modules of tea plant from the perspective of systems biology. We want to clarify the interaction between genes, and its upstream regulatory networks of tea plant responding to cold stress, and then try to probe into cold and freezing resistant mechanisms of tea plant from the transcriptional and post-transcriptional level. In this oncoming application, we will make great efforts to get some cold-resistant relative molecular markers and access to important functional genes and miRNAs with independent intellectual property rights. And our research will provide theoretical guidance for the next use of molecular markers for early identification of cold resistance of tea plant breeding.