端粒长度调控是干细胞与肿瘤领域的热点问题。我们最新研究发现下调Pwp1能快速引起胚胎干细胞（ES细胞）端粒长度的缩短，初步数据显示Pwp1参与了端粒长度调控的多种方式相关分子调控与结合（非端粒酶依赖的端粒加长机制相关因子Zscan4、H4K20me3以及端粒末端保护蛋白复合物Shelterin等）。为此，本课题拟以可诱导干扰/敲除Pwp1的ES细胞以及Pwp1条件性敲除小鼠为研究对象，通过ChIP-seq分析组蛋白H4K20me3/H3K9me3在敲除前后的差异性富集位点，CoIP/质谱分析与Pwp1结合的关键蛋白以及条件性敲除小鼠体内功能试验等方法，从端粒酶活性、非端粒酶依赖的端粒加长、组蛋白修饰以及端粒末端保护蛋白复合物Shelterin等方面系统的阐明Pwp1调控端粒长度的分子机制，为多能干细胞的临床应用以及解析端粒相关疾病的发生发展提供理论依据。

The regulation of telomere length is a hotspot in the areas of stem cell maintenance and tumorigenesis. Our recent study revealed that downregulation of Pwp1 could accelerate to shorten of telomere length in ES cells. Preliminary data showed that Pwp1 might be involved in the regulation of telomere length by a variety of signal regulatory pathway (alternative lengthening of telomeres relative factor Zscan4, H4K20me3 and telomere end protection protein shelterin complexes). Therefore, this project through the inducible shRNA / knockout of Pwp1 ES cells and Pwp1 knockout mice to clarify the role of Pwp1 in regulating telomere length determine whether Pwp1 regulates telomere length through telomerase activity, alternative lengthening of telomeres, histone modifications and the formation of telomere end protection protein complex shelterin in ES cells, and using the ChIP-seq analysis enrichment sites of histone H4k20me3 and H3K9me3 in knockout or wild type ES cells, and immunoprecipitation combined with mass spectrometry analysis key proteins combined with pwp1, and conditional knockout mice to test the function of pwp1,further revealing the molecular mechanisms of Pwp1 involving in telomere length regulation. Base on the study of our project, we would provide a theoretical basis for the development of pluripotent stem cells in clinical application and analysis of telomere regulating related diseases.