UCLA

Human immunodeficiency virus type 1 (HIV-1) replication requires the reverse transcription of its RNA genome into double-stranded DNA copies within the cytoplasm before integration into the host chromosome. Reverse transcriptase (RT) and integrase (IN) are the viral enzymes responsible for catalyzing the essential steps of reverse transcription and integration, respectively. While numerous studies have led to a greater understanding of the functional roles that RT and IN individually play in HIV-1 replication, little is known about the functional role of RT-IN complex formation in vivo. We hypothesize that RT-IN interaction has functional significance in HIV-1 reverse transcription and replication kinetics. We have mapped the putative binding domain of RT on IN to nine residues on the IN C-terminal domain (CTD). We tested the significance of RT-IN interaction on reverse transcription and viral replication, and identified the step at which viral replication of these IN mutants become defective. We observed impairment of viral cDNA synthesis in viruses harboring IN mutations at the putative RT-binding surface, supporting our hypothesis that the RT-IN interaction during the reverse transcription step is biologically relevant. We have developed a pharmacological approach to study and screen for inhibitors against the RT-IN interaction. Lastly, we have also initiated biochemical studies to determine the IN binding domain domain on RT to contribute to the full understanding of the binding mechanism.