CLE多肽激素调控维管形成层发育及分化的分子机制研究

Vascular cambium is the starting point of the secondary vascular system development in plants. The proliferation and differentiation of meristem cells in the cambium has always been one of the main research areas in tree growth. The objective of this project is to clarify the molecular mechanisms of one important peptide hormone, CLE, in controlling and influencing cell division and differentiation in vascular tissues. Based on the previous study of the CLE hormone receptor LRR-RLK, this project will combine the research tools including bioinformatics, molecular biology and functionalgenomics, and will take poplar and Arabidopsis as the models. Through prediction and comparison of the structures of CLE peptide hormones and their receptors; analysis of their spatial and temporal expression patterns; use of mutant resource and genetically modification for functional verification; identification of the conserved functional domains by gene mutation, we will study the universality and conservation of the expression and function of CLEpeptide hormones in vascular plants, and investigate its potential in genetic breeding. This project is of great significance to reveal the molecular mechanisms of vascular cambium development. It will help to systemically integrate the theory of wood formation and regulation, add new insights to the field of plant development biology,also provide a data and theoretical support for innovation of the forest breeding system in China to obtain novel forest tree varieties with high-quality and high-yield.

维管形成层是植物次生维管系统发育的起始点，形成层分生细胞的分裂与分化一直是树木生长发育领域的研究重点之一。本课题力图阐明一类重要的多肽类激素CLE在维管分生组织中控制和影响形成层细胞分裂和分化的分子机制。在前期对CLE激素受体LRR-RLK进行研究的基础上，结合生物信息学、分子生物学和功能基因组学等研究手段，以拟南芥和杨树为模型，通过预测比较CLE多肽激素的结构、掌握其时空变化规律、利用突变体资源及转基因手段进行功能验证、通过基因突变鉴定功能保守区等方法，对CLE多肽激素在表达及功能上的普遍性和保守性进行深入研究,同时对CLE转基因在林木育种中的应用前景等问题进行探讨。本课题对揭示维管形成层发育的分子调控机制具有重要意义，同时将有助于系统地整合林木木材形成与调控的理论，是对树木生长发育领域相关研究的重要补充，也为创新我国林木育种的技术体系，实现优质、高产林木育种提供理论支持与保障。

多肽激素参与植物生长发育及环境刺激应答反应中的多种信号传导途径，在植物生命活动中发挥着重要功能。本课题研究对象为多肽类激素CLE介导的信号转导途径中的各个组分，研究重点是其如何在分子水平上控制和影响植物分生组织内细胞的分裂和分化。我们对多种模式植物中的CLE基因家族成员和受体激酶家族成员进行了系统的生物信息学分析，比较了CLE多肽激素的蛋白结构进化、掌握了多肽激素及其受体激酶的时空表达变化规律。同时利用生化化学方法和基因组学手段进行了对信号途径中的多个关键基因进行了功能验证，对木本植物中CLE多肽激素表达及功能上的保守性和特异性进行了深入研究,同时也探讨了CLE信号转导途径在林木育种中的应用前景。本课题的研究成果对于建立CLE多肽激素调控林木维管系统分化的信号网络具有一定借鉴价值，是对多肽激素信号转导在树木发育生物学领域的重要补充，同时可为实现人工调控林木次生维管系统发育过程和进行材性改良奠定基础。