NF-κB-Driven HIV-1 Gene Expression in Human Cells Is Independent of Poly(ADP-ribose) polymerase-1 Function.

Abstract

The cellular enzyme poly (ADP-ribose) polymerase-1 (PARP-1) is required for NF-{kappa}B to activate inflammatory and immune response gene expression. NF-{kappa}B is also an important transcription factor in HIV-1 gene expression during active replication and latency reactivation. Therefore, enhancing NF-{kappa}B signaling is an alternative for HIV-1 latency reactivation, but significant systemic side effects related to the NF-{kappa}B role in inflammatory and immune responses are predictable. To verify this prediction, we determined whether PARP-1 is required in NF-{kappa}B-dependent HIV-1 gene expression in a human CD4+ T lymphoblastoid cell line (SUP-T1) and HEK 293T cells. Our findings indicated that PARP-1 knockout does not impair HIV-1 infection or gene expression. Specifically, NF-{kappa}B-dependent HIV-1 gene expression was not impaired by PARP-1 deficiency, highlighting an important transcriptional regulatory difference between HIV-1 and inflammatory and immune activation genes. Our findings define a negligible role of PARP-1 in HIV-1 gene expression, suggesting that PARP-1 antagonism could ameliorate the expected inflammatory response with latency-reactivating agents that act through the NF-{kappa}B signaling pathway. ImportancePARP-1 is required for NF-{kappa}B to activate the expression of inflammatory and immune response genes. NF-{kappa}B is also an important transcription factor in HIV-1 gene expression during active replication and latency reactivation. Enhancing NF-{kappa}B signaling is expected to cause HIV-1 latency reactivation, but significant systemic side effects related to the NF-{kappa}B role in inflammatory and immune responses are predictable. The role of PARP-1 in NF-{kappa}B-mediated activation of HIV-1 gene expression and in viral infection has not been determined in the context of HIV-1 infection of CD4+ T cells. Our data indicate that PARP-1 is dispensable for NF-{kappa}B-mediated activation of HIV-1 gene expression in a human CD4+ T lymphoblastoid cell line. These findings suggest that the pharmacological antagonism of PARP-1 could diminish the inflammatory effects of latency-reactivating agents that activate NF-{kappa}B signaling without impairing their effect on HIV-1 gene expression.