菊花转录因子CmTCP9 参与花瓣生长调控的分子机制研究

菊花是我国十大传统名花和世界四大切花之一，有很高的观赏和经济价值。TCP 转录因子家族参与植物的生长发育，与花器官形态建成有着密切关系，我们先前获得了18个菊花TCP 转录因子，发现CmTCP9 在切花菊‘神马’花瓣中表达量最高。超表达CmTCP9 能使拟南芥花瓣明显变长、变宽，但其参与菊花花瓣生长调控的分子机制尚不清楚。本项目拟分析CmTCP9 表达特性、亚细胞定位、转录激活活性，阐述其在花瓣生长发育过程中的基本功能；构建超表达和功能沉默载体获得转基因材料，分析转基因植株与对照株系转录本表达差异，找出CmTCP9 的候选下游基因；通过酵母双杂交筛选CmTCP9 的互作蛋白，并使用双分子荧光互补、Pull-down和免疫共沉淀等手段进行体内、外验证，最终阐释CmTCP9 参与菊花花瓣生长的作用，解析其在花瓣生长调控中的具体机制，为菊花花器官的分子育种奠定基础，具有重要科学意义和应用前景。

Chrysanthemum (Chrysanthemum morifolium), one of the ten traditional famous flower and one of four important cut flowers over the world, is of high ornamental and economic values. The TCP transcription factor family is unique to plants, and is closely related with plant growth and flower petal development. We have previously cloned 18 candidate TCP genes, among these, CmTCP9 shown high transcript abundance in petals. Overexpression of CmTCP9 shown larger and longer petals in A. thaliana, however, the mechanism involved in regulating petal growth in chrysanthemum remained unclear. The present proposal aimed to identify its function by analyzing the expression pattern of the CmTCP9, its subcellular localization and transcriptional activation activity; to obtain the CmTCP9 overexpressed and silenced gene function transgenic plant lines; to screen and verify genes regulated downstream by CmTCP9 using bioinformatics analysis; to screen its interaction proteins using yeast two-hybrid, to confirm the interaction in vitro and in vivo using bimolecular fluorescence complementation, and GST Pull-down and Co-Immunoprecipitation. Taken together, the present proposal will disclose the mechanism of CmTCP9 in regulating petal of chrysanthemum, which will provide theoretical basis for molecular breeding. Therefore, the present proposal is of both theoretical and practical significance.