Recruitment and activation of RSK2 by HIV-1 Tat.

Recruitment and activation of RSK2 by HIV-1 Tat.

Blog Article

The transcriptional activity of the integrated HIV provirus is dependent on the chromatin organization of the viral promoter 7 Piece Queen Bedroom and the transactivator Tat.Tat recruits the cellular pTEFb complex and interacts with several chromatin-modifying enzymes, including the histone acetyltransferases p300 and PCAF.Here, we examined the interaction of Tat with activation-dependent histone kinases, including the p90 ribosomal S6 kinase 2 (RSK2).Dominant-negative RSK2 and treatment with a small-molecule inhibitor of RSK2 kinase activity inhibited the transcriptional activity of Tat, indicating that RSK2 is important for Tat function.

Reconstitution of RSK2 in cells from subjects with a genetic defect in RSK2 expression (Coffin-Lowry syndrome) enhanced Tat transactivation.Tat interacted with RSK2 and activated RSK2 kinase activity in cells.Both properties were lost in a mutant Tat protein (F38A) that is deficient in HIV transactivation.Our data identify a novel reciprocal regulation of Tat and RSK2 function, which might serve to induce early changes in the chromatin organization Conditioner Bar of the HIV LTR.