Preliminary NMR investigation of Tat alternative splicing regulation in HIV-1

Splicing of the HIV-1 primary transcript is highly regulated. Maintenance of proper equilibrium among spliced, unspliced and partially spliced transcripts is essential for replication of the virus. Interaction between an RNA sequence within tat exon 2, called the proximal exonic splicing silencer two (pESS2), and its binding protein, the heterogeneous nuclear ribonucleoprotein H (hnRNP H), is crucial for the splicing regulation of the upstream intron. A preliminary structural study of the two biomolecules forming the complex is presented. The biomolecules design strategy chosen to make the analysis feasible by NMR and their production is presented. The first NMR data establishing the RNA secondary structure is shown, along with the preliminary NMR results obtained with the protein constructs. They found the feasibility of the structural project.