The long-term goal of this project is to understand the role of TIA-1 and TIAR in cellular metabolism. Our working hypothesis is that these proteins bind to specific subsets of mRNAs to regulate their translation, perhaps in response to environmental stress. The proposed project will promote this end by examining functional interactions between TIAR and its putative TIA-1 mRNA substrate in intact cells. Analysis of this prototypical interaction will enable us to assess additional potential substrates by nucleotide homology, to further our understanding of these RNA-binding proteins in their proposed role in the stress response.