CpMYB2不同等位基因在蜡梅中的功能分化及其呈色机理研究

蜡梅是原产于中国的重要冬季观花灌木，有很高的观赏价值。前期工作发现，转录因子CpMYB2存在6个不同等位基因，其中一个是无义突变；无义突变与蜡梅花内被片有无花青素直接相关。不同等位基因的组合使蜡梅呈现出素心、晕心、红心等表型。目前，CpMYB2是如何调控蜡梅花青素合成有关基因的机制尚不明确。本研究拟转化蜡梅原生质体和拟南芥以明确CpMYB2不同等位基因的功能；筛选它们的下游调控基因，并用酵母单杂交、荧光素酶瞬时表达实验以及EMSA技术加以体内体外验证；筛选CpMYB2的蛋白互作复合体，并用BiFC和GST-pulldown技术验证；分析F2代群体的基因型-表型分离规律。本项目有望从分子生物学和遗传学上阐明等位基因功能分化在着色中的作用、CpMYB2的作用机制、不同花色蜡梅品种群的形成机理，完善观赏植物的花色理论，为蜡梅的花色分子育种提供科学依据。

Chimonanthus praecox, native to China, is an important winter flowering shrub with high ornamental value. Based on our previous work, 6 alleles occurred in the R2R3 transcription factor CpMYB2, one of which is a nonsense mutation. It was found that the nonsense mutation is directly related to the absence of anthocyanin, and the combination of the different alleles determines the pigmentation strength on the inner tepals in wintersweet. However, the genetic and molecular bases of how CpMYB2 ultimately determine the flower colour traits remain poorly understood. The study was designed to verity the function of CpMYB2 by transforming Arabidopsis and the protoplasts of wintersweet; to screen and verify the downstream structural genes in vivo and in vitro by applying yeast one hybrid, luciferase transient expression and EMSA assays; to screen and test the protein interaction complexes by using yeast two hybrid, BiFC and GST-pulldown technique; to screen genotypes and phenotypes in F2 hybrid populations. This project is expected to elucidate the functional divergence of different alleles, the mechanism of CpMYB2, and to make clear the origin of different varieties in wintersweet in the perspective of genetics and molecular biology. The results would improve the flower color theory of ornamental plants and provide solid basis for the molecular breeding in wintersweet.