原生动物四膜虫生殖小核(germline nucleus)体功能(somatic function)的分子基础研究

One of the most important problems in biology is the relationship between germline and soma. The ciliated protozoa, which have the differentiation of germline nucleus (micronucleus) and somatic nucleus (macronucleus), naturally become the good material to study the germline-soma relationship. Although mainly function as germline reserve, the germline nucleus of ciliates showed some somatic functions, and this provide new insight to the germline-soma relationship. However, the molecular basis of somatic functions controlled by germline nucleus is not clear. Focus on this question, this application propose to use ciliated protozoan - Tetrahymena thermophila as material, and perform comparative genomics and whole transcriptomics analysis to identify the DNA sequences which control the somatic functions in germline nucleus. Then, experiments will be done to investigate the molecular functions for the identified DNA sequences, and try to elucidate the molecular mechanism. Finally, the above findings will help to discuss the relationship between germline nucleus and somatic nucleus in single-celled ciliates, and also improve the understanding about the relationship and division of labor between germline and soma in multicellular organism.

生殖系（germline）与体细胞系（soma）的关系是生物学中最重要的问题之一。而具有生殖核（小核）和体核（大核）分化的原生动物纤毛虫正是在单细胞水平研究生殖系与体细胞系之间关系的优良材料。虽然保存遗传信息是纤毛虫生殖小核的主要功能，但其还具有一定的体功能，使得研究者对生殖系与体细胞系之间的关系有了新认识。针对纤毛虫生殖小核体功能的分子基础尚不清楚这一问题，本项目提出以纤毛虫-嗜热四膜虫为突破口，以比较基因组和比较全转录组分析为主要研究手段，鉴定嗜热四膜虫中控制生殖小核体功能的DNA序列，并在基础上开展功能分析，阐明生殖小核体功能的分子基础，探讨单细胞纤毛虫生殖核与体核的关系，增进对多细胞生物生殖系与体细胞系之间的关系及其进化分工的认识。

生殖系（germline）与体细胞系（soma）的关系是生物学中最重要的问题之一。而具有生殖核（小核）和体核（大核）分化的原生动物纤毛虫正是在单细胞水平研究生殖系与体细胞系之间关系的优良材料。本项目以纤毛虫-嗜热四膜虫为突破口，以比较基因组和转录组分析为主要研究手段，筛选了嗜热四膜虫中控制生殖小核体功能的DNA序列。取得主要结果包括：1）建立了纤毛虫高质量大核基因组以及完成图组装的重要技术方法; 2) 获得了嗜热四膜虫大、小核的基因组完成图，为以模式嗜热四膜虫的研究体功了重要的基础资源; 3) 筛选到了嗜热四膜虫小核体功相关的DNA元件库; 4) 厘清了转录因子ZFP1在四膜虫有性生殖和小核发育过程中的重要作用。研究结果对理解生物生殖系与体细胞系之间的关系及其进化分工具有重要意义