解脂耶氏酵母新型转录因子Fts1和Fts2负调控二型性转换的机制研究

解脂耶氏酵母是一种具有工业发酵用途的非常规酵母种类，同时，它也是一种二型性酵母，在某些环境因子的作用下，能够从酵母形态转变为菌丝或假菌丝。二型性转换对于解脂耶氏酵母适应环境较为重要，探索其调控机制具有重要科学价值。不同于研究较多的酿酒酵母和白色念珠菌，解脂耶氏酵母与它们在进化上相距较远，其二型性转换的调控因子也与它们存在较大差异。近期，本课题组通过遗传筛选在解脂耶氏酵母中鉴定得到两个新的二型性转换负调控因子Fts1和Fts2，它们在二型性转换中发挥着极为重要的负调控功能，但是却与之前在酿酒酵母和白色念珠菌中已发现的负调控因子属于不同类型。本项目将针对Fts1与Fts2这两个新型二型性转换负调控因子进行研究，揭示其细胞学功能、调控的靶基因、DNA识别位点以及受调控的机制，阐明Fts1和Fts2负调控二型性转换的机制。本项目对于揭示解脂耶氏酵母二型性转换的调控机制具有重要意义。

Yarrowia lipolytica is a non-conventional yeast species with applications in industrial fermentation. It is also a dimorphic yeast that is capable of converting from the yeast form to hyphae or pseudohyphae under certain environmental conditions. Dimorphic transition is important for the adaptation of Y. lipolytica to the environmental change. It is of scientific value to study the regulatory mechanisms that govern this morphological transition. Different from the two well-studied yeast species Saccharomyces cerevisiae and Candida albicans, Y. lipolytica is evolutionarily distant from them and so are the regulators of dimorphic transition in Y. lipolytica. Recently, our lab has identified two novel negative regulators of dimorphic transition in Y. lipolytica, Fts1 and Fts2. They play critical roles in the repression of dimorphic transition, yet differ from those known functional counterparts in either S. cerevisiae or C. albicans with repect to the transcription factor type. In this proposal, we plan to focus on these two novel transcription factors Fts1 and Fts2 and explore their cellular functions, downstream target genes, DNA recognition sites and the regulation on them. Our aim is to elucidate the mechanisms by which Fts1 and Fts2 repress dimorphic transition. Our proposed investigation will provide new insight in the understanding of the regulations on yeast dimorphic transition.