The studies proposed will examine the mechanism of translation repression of bacteriophage T4 genes by the T4 regA protein. To better understand how regA protein recognizes and represses translation of specific T4 mRNAs the PI will attempt to identify the targets recognized by regA protein on three T4 mRNAs. From these studies she will propose a model recognition element, incorporating the necessary characteristics of each of the three sites. The PI will then test the validity of the model by a) inserting the proposed recognition element into a non-regA target gene, and testing for regA sensitivity and b) measuring the effects of mutations in the gene 44 recognition element on synthesis of 44P in vivo and in vitro. To identify residues or domains of regA protein that are critical for RNA binding partial proteolysis in vitro mutagenesis of regA protein will be employed. These studies are designed to provide new insights into protein: RNA interactions that play critical roles in the control of gene expression. A full understanding of the mechanism of translational regulation of gene expression will help to answer larger questions concerning infection and replication of viruses and control of cell growth and differentiation.
