Structural Dynamics of Protein-RNA Complexes

描述（由申请人提供）：I族内含子是RNA基因中的非编码区域，能够通过自剪接机制切除。尽管存在热力学和动力学方面的挑战，内含子必须折叠成正确的天然结构来催化反应。来自粗神经孢子虫线粒体RNA的两个I组内含子依赖于蛋白质辅助因子CYT-18折叠成正确的自剪接结构。第二种蛋白质，CYT-19，加速这些蛋白质结合内含子的剪接速率。为了研究粗糙新孢子虫的多蛋白- rna相互作用，将使用单分子荧光检测源自内含子的核酶。通过RNA的位点特异性染料标记，将监测特定区域和单个分子的单三级相互作用的结构动力学。与催化活性构象相关的结构转变将遵循蛋白质- rna复合物。这项工作将有助于剖析蛋白质在补偿RNA折叠缺陷方面的进化作用。在该模型系统中探索rna -蛋白相互作用的技术可能有助于为未来探索更复杂的健康相关系统的方法提供基础。

DESCRIPTION (provided by applicant): Group I introns are non-coding regions in RNA genes that are capable of excision through a self-splicing mechanism. The introns must fold to the correct native structure to catalyze the reaction despite thermodynamic and kinetic challenges. Two of the group I introns from the Neurospora crassa mitochondrial RNA are dependent on a protein cofactor, CYT-18, to fold to the correct structure for self-splicing. A second protein, CYT-19, accelerates the splicing rate for these protein-bound introns. To investigate the multiprotein-RNA interactions in Neuospora crassa, ribozymes derived from the introns will be examined using single molecule fluorescence. Through site-specific dye-labeling of the RNA, the structural dynamics of specific domains and single tertiary interactions for individual molecules will be monitored. Structural transitions associated with the catalytically active conformation will be followed for the protein-RNA complexes. The work will help to dissect the evolutionary role of proteins in compensating for deficiencies in RNA folding. The techniques developed in exploring the RNA-protein interactions in this model system may aid in providing the basis for future methodologies to probe more complicated health-related systems.