PMID- 21763495 OWN - NLM STAT- MEDLINE DCOM- 20110913 LR - 20211020 IS - 1089-8638 (Electronic) IS - 0022-2836 (Print) IS - 0022-2836 (Linking) VI - 410 IP - 5 DP - 2011 Jul 29 TI - T-cell receptor signaling enhances transcriptional elongation from latent HIV proviruses by activating P-TEFb through an ERK-dependent pathway. PG - 896-916 LID - 10.1016/j.jmb.2011.03.054 [doi] AB - Latent human immunodeficiency virus (HIV) proviruses are thought to be primarily reactivated in vivo through stimulation of the T-cell receptor (TCR). Activation of the TCR induces multiple signal transduction pathways, leading to the ordered nuclear migration of the HIV transcription initiation factors NF-kappaB (nuclear factor kappaB) and NFAT (nuclear factor of activated T-cells), as well as potential effects on HIV transcriptional elongation. We have monitored the kinetics of proviral reactivation using chromatin immunoprecipitation assays to measure changes in the distribution of RNA polymerase II in the HIV provirus. Surprisingly, in contrast to TNF-alpha (tumor necrosis factor alpha) activation, where early transcription elongation is highly restricted due to rate-limiting concentrations of Tat, efficient and sustained HIV elongation and positive transcription elongation factor b (P-TEFb) recruitment are detected immediately after the activation of latent proviruses through the TCR. Inhibition of NFAT activation by cyclosporine had no effect on either HIV transcription initiation or elongation. However, examination of P-TEFb complexes by gel-filtration chromatography showed that TCR signaling led to the rapid dissociation of the large inactive P-TEFb:7SK RNP (small nuclear RNA 7SK ribonucleoprotein) complex and the release of active low-molecular-weight P-TEFb complexes. Both P-TEFb recruitment to the HIV long terminal repeat and enhanced HIV processivity were blocked by the ERK (extracellular-signal-regulated kinase) inhibitor U0126, but not by AKT (serine/threonine protein kinase Akt) and PI3K (phosphatidylinositol 3-kinase) inhibitors. In contrast to treatment with HMBA (hexamethylene bisacetamide) and DRB (5,6-dichlorobenzimidazole 1-beta-ribofuranoside), which disrupt the large 7SK RNP complex but do not stimulate early HIV elongation, TCR signaling provides the first example of a physiological pathway that can shift the balance between the inactive P-TEFb pool and the active P-TEFb pool and thereby stimulate proviral reactivation. CI - Copyright (c) 2011 Elsevier Ltd. All rights reserved. FAU - Kim, Young Kyeung AU - Kim YK AD - Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Room W200, Cleveland, OH 44106-4960, USA. FAU - Mbonye, Uri AU - Mbonye U FAU - Hokello, Joseph AU - Hokello J FAU - Karn, Jonathan AU - Karn J LA - eng GR - R01 AI067093-04/AI/NIAID NIH HHS/United States GR - DP1 DA028869-01/DA/NIDA NIH HHS/United States GR - R01 AI067093-03/AI/NIAID NIH HHS/United States GR - P30 AI036219-15/AI/NIAID NIH HHS/United States GR - DP1 DA028869/DA/NIDA NIH HHS/United States GR - P30 AI036219-16A1/AI/NIAID NIH HHS/United States GR - P30-AI036219/AI/NIAID NIH HHS/United States GR - D43 TW000011/TW/FIC NIH HHS/United States GR - R01 AI067093-05/AI/NIAID NIH HHS/United States GR - DP1-DA028869/DA/NIDA NIH HHS/United States GR - 5D43-TW00011/TW/FIC NIH HHS/United States GR - R01 AI067093/AI/NIAID NIH HHS/United States GR - DP1 DA028869-02/DA/NIDA NIH HHS/United States GR - R01-AI067093/AI/NIAID NIH HHS/United States GR - P30 AI036219/AI/NIAID NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Research Support, Non-U.S. Gov't PL - Netherlands TA - J Mol Biol JT - Journal of molecular biology JID - 2985088R RN - 0 (Butadienes) RN - 0 (CCNT1 protein, human) RN - 0 (Chromatin) RN - 0 (Chromones) RN - 0 (Cyclin T) RN - 0 (Morpholines) RN - 0 (NFATC Transcription Factors) RN - 0 (Nitriles) RN - 0 (Receptors, Antigen, T-Cell) RN - 0 (Ribonucleoproteins) RN - 0 (U 0126) RN - 0 (tat Gene Products, Human Immunodeficiency Virus) RN - 31M2U1DVID (2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one) RN - EC 2.7.11.- (Positive Transcriptional Elongation Factor B) RN - EC 2.7.11.22 (CDK9 protein, human) RN - EC 2.7.11.22 (Cyclin-Dependent Kinase 9) RN - EC 2.7.11.24 (Extracellular Signal-Regulated MAP Kinases) RN - NI40JAQ945 (Tetradecanoylphorbol Acetate) SB - IM MH - Butadienes/pharmacology MH - Chromatin/metabolism MH - Chromones/pharmacology MH - Cyclin T/metabolism MH - Cyclin-Dependent Kinase 9/metabolism MH - Extracellular Signal-Regulated MAP Kinases/*metabolism MH - HIV/drug effects/*genetics/physiology MH - Humans MH - Jurkat Cells MH - Kinetics MH - Morpholines/pharmacology MH - NFATC Transcription Factors/metabolism MH - Nitriles/pharmacology MH - Positive Transcriptional Elongation Factor B/*metabolism MH - Protein Binding/drug effects MH - Proviruses/drug effects/*genetics/physiology MH - Receptors, Antigen, T-Cell/*metabolism MH - Ribonucleoproteins/metabolism MH - *Signal Transduction/drug effects MH - Tetradecanoylphorbol Acetate/pharmacology MH - *Transcription, Genetic/drug effects MH - Virus Activation/drug effects MH - Virus Latency/drug effects MH - tat Gene Products, Human Immunodeficiency Virus/metabolism PMC - PMC3139146 MID - NIHMS291662 EDAT- 2011/07/19 06:00 MHDA- 2011/09/14 06:00 PMCR- 2012/07/29 CRDT- 2011/07/19 06:00 PHST- 2011/02/04 00:00 [received] PHST- 2011/03/20 00:00 [revised] PHST- 2011/03/24 00:00 [accepted] PHST- 2011/07/19 06:00 [entrez] PHST- 2011/07/19 06:00 [pubmed] PHST- 2011/09/14 06:00 [medline] PHST- 2012/07/29 00:00 [pmc-release] AID - S0022-2836(11)00343-3 [pii] AID - 10.1016/j.jmb.2011.03.054 [doi] PST - ppublish SO - J Mol Biol. 2011 Jul 29;410(5):896-916. doi: 10.1016/j.jmb.2011.03.054.