Mechanisms and Applications of RNA-mediated Enzymes in Translation and Immunity

Description: RNA-guided, or ribonucleoprotein particle (RNP), enzymes comprise an emerging class of molecules that function in a wide range of biological pathways. Unlike most of the protein-based enzymes, RNP enzymes rely on the guide RNA to secure the substrates and on the partner proteins to catalyze the chemical reactions. The RNA-guided targeting mechanism has created unprecedented opportunities in genome manipulation, gene regulation and nucleic acid detection. Research in the Li laboratory employs structural biology and complementary methods to uncover the theoretical basis for their biological function and effective use as research, diagnostic and therapeutic tools. In the proposed funding period, the Li laboratory will tackle the mechanisms of the RNP enzymes to enable their applications. These include the methylation-sensitive Clustered, Regularly Interspaced, Short Palindromic Repeats (CRISPR)-Cas9, the multi-functional Type III CRISPR effectors and their associated signaling processes, and the small nucleolar RNPs (snoRNPs) responsible for chemical modifications of ribosomal RNA. Though unrelated in enzyme composition or biological pathway, these RNP enzymes are governed by a similar set of physicochemical principles and share the great potential in therapeutic and diagnostic innovations by reprogramming the chemistry of cellular nucleic acids. The proposed research will assess the feasibility of engineering and applying the epigenetic DNA-specific Cas9, the utility of rapid virus detection with the CRISPR Type III effectors, and the possibility of tunning cellular functions through chemical modifications of RNA. The Li laboratory has assembled a team of scientists with complementary expertise in microbiology, mammalian genome biology, yeast genetics, single molecule biophysics, virology, virus detection, X-ray crystallography, and high-throughput cryogenic electron microscopy to maximize the impact while mitigating the risks of the research. The goal of this transformative proposal is to demonstrate and enable the applicability of the RNA-mediated enzymes in a wide range of biomedical fields.