Function and Mechanism of Coat Protein Complex I in RNA Silencing

Texas A&M Agrilife Research, College Station TX

Investigators

Abstract

This project focuses on the role of Coat protein complex I (COPI) in transporting a group of enzymes to the right places inside plant cells to perform regulatory functions, including degradation of mRNA and inhibition of protein synthesis. By enhancing understanding of the mechanisms of gene silencing, this project can enhance biotechnological approaches to improve agricultural crops. This project will also incorporate research experiences into a Genetics course to strengthen the teaching of genomics to undergraduates. The project also provides hands-on training for high school students in genetics and biology. The goal of this project is to elucidate how COPI contributes to miRNA-mediated RNA silencing. miRNAs are a group of small noncoding regulatory RNAs that suppress expression of endogenous genes and invasive RNAs. miRNAs are loaded into Argonaute proteins to form RNA-induced silencing complexes (mi-RISC) that in return destroy target RNAs. Although key components and auxiliary partners of mi-RISC have been identified and studied, many new regulatory layers or factors are still being recovered; and the precise mechanisms remain to be exploited. Using a novel genetic screening approach, the PI has identified a new gene, α2-COP that encodes a subunit of COPI, as a new player in the miRNA pathway. The central hypothesis is that COPI is responsible for delivering components of mi-RISC and/or P-bodies to their functional sites to impact RNA silencing. The PI will apply a series of genetic, cell biological and biochemical approaches to test this hypothesis. Functional and mechanistic analyses of COPI will not only reveal new regulatory layers and mechanisms of RNA silencing, but also enable us to improve the efficacy of RNAi technology. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.