生物节律是一种生物内在的、复杂而精细的生理调节系统，它使植物得以根据外界环境的周期性变化来协调自身新陈代谢及各种生理过程，从而与环境保持同步。以往对于生物钟节律的研究对象多以拟南芥或草本等一年生植物为主，而直接反应多年生植物特别是多年生木本杨属植物生物钟节律的分子机理研究甚少。杨树生物钟节律的分子机制是什么？PRRs基因家族的功能是什么？PRRs家族相关成员是如何调控的？这些关键科学问题的解决对杨树生长发育的研究具有重要意义。本项目利用高通量测序技术获得杨树全基因组昼夜节律不同时段转录组数据，在杨树基因组序列信息的基础上，克隆鉴定杨树生物钟节律PRRs基因家族，并结合荧光定量PCR技术和过表达及RNAi技术，分析杨树生物钟节律PRRs基因家族功能及分子调控机制。本项目研究成果将为杨树遗传改良提供理论依据。

Biological rhythm is a biological internal, complex and sophisticated physiological regulation system, and it makes the plants able to coordinate their own metabolism and physiological processes according to the periodic changes in the external environment, so as to keep pace with the environment. In the past, the research of circadian rhythms focused on Arabidopsis or herbaceous annual plant, and there were little reports on molecular mechanism of circadian rhythms of the perennial plants especially the woody perennial plants such as Populus. What is the molecular mechanism of poplar circadian rhythms? What is the function of PRRs gene family? How do the related members of the PRRs family control each other? It is important to solve these key scientific problems for study of poplar growth. This project is to use high-throughput sequencing transcriptome data during different key time of circadian rhythm, and based on the poplar genome sequence information, we will clone and identify PRRs gene family related to the circadian rhythms. Combined fluorescent quantitative PCR technique and over expression and RNAi technology, this project will analyze the function and the control mechanism of the poplar PRRs gene family related to circadian rhythms. This research will provide theoretical basis for genetic improvement of poplar.