The large subunit of HIV-1 reverse transcriptase interacts with β-actin

ABSTRACT HIV-1 reverse transcriptase is a dimeric enzyme mainly Involved in the replication of the viral genome. A filamentous phage cDNA expression library from human lymphocytes was used to select cellular proteins interacting with HIV-1 reverse transcriptase. Affinity selections using the bacterially expressed monomeric large subunit of reverse transcriptase (p66) yielded host β-actin. This clone was expressed as glutathione-S-transferase fusion protein which was identified by using a specific antibody against β-actin. Furthermore we show that also the eukaryotic β-actin binds to either the large subunit of reverse transcriptase or to the Pol precursor polyprotein in vitro. The reverse transcriptase/β-actin interaction might be important for the secretion of HIV-1 virions.