Transcription elongation regulator 1 (TCERG1) regulates competent RNA polymerase II-mediated elongation of HIV-1 transcription and facilitates efficient viral replication

BACKGROUND: Control of RNA polymerase II (RNAPII) release from pausing has been proposed as a checkpoint mechanism to ensure optimal RNAPII activity, especially in large, highly regulated genes. HIV-1 gene expression is highly regulated at the level of elongation, which includes transcriptional paus...

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Detalhes bibliográficos
Autores: Coiras, Mayte, Montes, Marta, Montanuy, Immaculada, Lopez-Huertas, Maria Rosa, Mateos, Elena, Le Sommer, Caroline, Garcia-Blanco, Mariano A, Hernández-Munain, Cristina, Alcamí, José, Suñé, Carlos
Tipo de documento: artigo
Data de publicação:2013
País:España
Recursos:Instituto de Salud Carlos III (ISCIII)
Repositório:Repisalud
Idioma:inglês
OAI Identifier:oai:repisalud.isciii.es:20.500.12105/7103
Acesso em linha:http://hdl.handle.net/20.500.12105/7103
Access Level:Acceso aberto
Palavra-chave:Cell Line
HIV-1
Humans
RNA Polymerase II
Transcriptional Elongation Factors
Transcription, Genetic
Virus Replication
Descrição
Resumo:BACKGROUND: Control of RNA polymerase II (RNAPII) release from pausing has been proposed as a checkpoint mechanism to ensure optimal RNAPII activity, especially in large, highly regulated genes. HIV-1 gene expression is highly regulated at the level of elongation, which includes transcriptional pausing that is mediated by both viral and cellular factors. Here, we present evidence for a specific role of the elongation-related factor TCERG1 in regulating the extent of HIV-1 elongation and viral replication in vivo. RESULTS: We show that TCERG1 depletion diminishes the basal and viral Tat-activated transcription from the HIV-1 LTR. In support of a role for an elongation mechanism in the transcriptional control of HIV-1, we found that TCERG1 modifies the levels of pre-mRNAs generated at distal regions of HIV-1. Most importantly, TCERG1 directly affects the elongation rate of RNAPII transcription in vivo. Furthermore, our data demonstrate that TCERG1 regulates HIV-1 transcription by increasing the rate of RNAPII elongation through the phosphorylation of serine 2 within the carboxyl-terminal domain (CTD) of RNAPII and suggest a mechanism for the involvement of TCERG1 in relieving pausing. Finally, we show that TCERG1 is required for HIV-1 replication. CONCLUSIONS: Our study reveals that TCERG1 regulates HIV-1 transcriptional elongation by increasing the elongation rate of RNAPII and phosphorylation of Ser 2 within the CTD. Based on our data, we propose a general mechanism for TCERG1 acting on genes that are regulated at the level of elongation by increasing the rate of RNAPII transcription through the phosphorylation of Ser2. In the case of HIV-1, our evidence provides the basis for further investigation of TCERG1 as a potential therapeutic target for the inhibition of HIV-1 replication.