RNPs regulating C. elegans germline development.  We are using a biochemical and structural biology approach to determine the structure of RNA-protein complexes that regulate stem cell differentiation in the model organism C. elegans.  RNA binding proteins regulate many essential genes in this process by binding to 3'untranslated regions of the mRNA.  We are using X-ray crystallography to determine the structures of these multicomponent ribonucleoprotein complexes to learn how they regulate gene expression.

Regulation of T-cell activation by RNA binding proteins.  We are collaborating with Dan Salomon's laboratory to study how RNA binding proteins regulation the activation of T-cells.  We are using a structural genomics approach to determine the structure of RNA binding proteins, protein-protein complexes, and RNA-protein complexes that are implicated in regulating T-cell activation. 

Helicases involved in HIV Replication.  We are studying a set of helicases that are implicated in the function of the HIV Rev protein, which is important for transport of unspliced viral mRNAs from the nucleus to the cytoplasm.  Helicases are ATP-dependent RNA binding motors that are implicated in strand displacement and protein displacement reactions in many cellular processes, however, their specific role in HIV replication is not known.  We are taking a biochemical and X-ray crystallographic approach to understand how these helicases participate in key steps of the life cycle of HIV.