CELLULAR PROTEINS Hsp60 AND SAHH AS NEGATIVE REGULATORS OF EARLY STAGES OF HIV-1 REPLICATION

The increasing over-time HIV-1 resistance to drugs targeting viral proteins necessitates the search for new targets, including blockers of interactions between viral and cellular proteins. Inhibitors of binding have already been identified for two cellular proteins (LEDGF/p75 and Ku70) that interact with viral integrase, reducing replication efficiency. Previously, using cross-linking and co-immuno-precipitation followed by mass spectrometry, several new cellular potential partners of HIV-1 integrase were discovered, including the chaperonin Hsp60 and adenosylhomocystein hydrolase SAHH. In this study, we demonstrated that these purified recombinant proteins co-precipitate in vitro with integrase, indicating their ability to directly interact with it. It was found that knockdown of Hsp60 and SAHH in human cells enhances the efficiency of HIV-1-based pseudovirus transduction. Moreover, this effect occurs specifically at the early stages of HIV-1 replication rather than at the proviral transcription stage. Additionally, we were able to determine the stage of the HIV-1 replication cycle affected by these proteins. It was shown that Hsp60 knockdown stimulates integration, while SAHH knockdown increases the efficiency of viral reverse transcription, in which integrase is also involved.