冰岛硫化叶菌CRISPR-Cas10系统（Cmr-β）多重核酸干涉活性的分子机制

CRISPR-Cas系统是通过小的向导RNA介导的方式来消灭外源核酸物质从而保护古菌和细菌的获得性免疫系统。近年来，申请人等先后揭示了冰岛硫化叶菌CRISPR-Cas10系统（Cmr-α）的RNA干涉活性和靶标RNA激活的DNA干涉活性的分子机理，并开发了基于内源CRISPR系统的基因组编辑技术，该技术已在含有活性内源CRISPR-Cas系统的原核生物中广泛应用。特别的是，我们发现冰岛硫化叶菌另一套CRISPR-Cas10系统（Cmr-β）的组成及核酸干涉活性均与Cmr-α系统有着显著区别。在本项目中，申请人将以冰岛硫化叶菌CRISPR-Cas10系统（Cmr-β）为研究对象，分析Cmr-β核酸蛋白复合体的组分，并解析其多重核酸干涉活性的调控模式和分子机理。该研究将为CRISPR-Cas10系统的应用开发奠定基础。

CRISPR-Cas systems provide adaptive immunity against invasive nucleic acids in a small RNA (crRNA)-guided fashion in archaea and bacteria. In the past few years, we have revealed the molecular mechanism of RNA interference and RNA-activated DNA interference activity by a Sulfolobus islandicus CRISPR-Cas10 system (Cmr-α), and developed the endogenous CRISPR-based genome editing techniques, which have been extensively applied in prokaryotes with active endogenous CRISPR-Cas systems. Notably, we found that the composition and nucleic acid interference activities of a second CRISPR-Cas10 system, Cmr-β, were very different from Cmr-α. In this project, the applicant will analyze the composition of Cmr-β ribonucleoprotein complex, and aims to reveal the regulation and mechanism of multiple nucleic acid interference of Cmr-β system. The results to be obtained in this study will establish a solid foundation for developing CRISPR technology with CRISPR-Cas10 systems.