c-Myc and Sp1 contribute to proviral latency by recruiting histone deacetylase 1 to the human immunodeficiency virus type 1 promoter.
Histone deacetylase (HDAC) inhibitors such as valproic acid (VPA) induce the expression of quiescent proviral human immunodeficiency virus type 1 (HIV-1) and may deplete proviral infection in vivo. To uncover novel molecular mechanisms that maintain HIV latency, we sought cellular mRNAs whose expression was diminished in resting CD4(+) T cells of HIV-1-infected patients exposed to VPA. c-Myc was prominent among genes markedly downregulated upon exposure to VPA. c-Myc expression repressed HIV-1 expression in chronically infected cell lines. Chromatin immunoprecipitation (ChIP) assays revealed that c-Myc and HDAC1 are coordinately resident at the HIV-1 long terminal repeat (LTR) promoter and absent from the promoter after VPA treatment in concert with histone acetylation, RNA polymerase II recruitment, and LTR expression. Sequential ChIP assays demonstrated that c-Myc, Sp1, and HDAC1 coexist in the same DNA-protein complex at the HIV promoter. Short hairpin RNA inhibition of c-Myc reduces both c-Myc and HDAC1 occupancy, blocks c-Myc repression of Tat activation, and increases LTR expression. These results expand the understanding of mechanisms that recruit HDAC and maintain the latency of HIV-1, suggesting novel therapeutic approaches against latent proviral HIV infection.
Jiang
Guochun
G
Department of Medicine, University of North Carolina at Chapel Hill, 3302 Michael Hooker Research Ctr., Chapel Hill, NC 27599-7435, USA.
Espeseth
Amy
A
Hazuda
Daria J
DJ
Margolis
David M
DM
D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D016325:HIV Long Terminal Repeat; D015497:HIV-1 / Q000235:genetics*; D056284:Histone Deacetylase 1; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases / Q000378:metabolism*; D006801:Humans; D011401:Promoter Regions, Genetic; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics*; D016329:Sp1 Transcription Factor / Q000235:genetics*; D014635:Valproic Acid / Q000494:pharmacology; D017735:Virus Latency / Q000187:drug effects
D056572:Histone Deacetylase Inhibitors; C489427:MYC protein, human; D016271:Proto-Oncogene Proteins c-myc; D016329:Sp1 Transcription Factor; D014635:Valproic Acid; C110550:HDAC1 protein, human; D056284:Histone Deacetylase 1; D006655:Histone Deacetylases