title: HIV-1 transcriptional silencing caused by TRIM22 inhibition of Sp1 binding to the viral promoter
creator: Turrini, Filippo
creator: Marelli, Sara
creator: Kajaste-Rudnitski, Anna
creator: Lusic, Marina
creator: Van Lint, Carine
creator: Das, Atze T.
creator: Harwig, Alex
creator: Berkhout, Ben
creator: Vicenzi, Elisa
subject: 570
subject: 570 Life sciences
subject: 610
subject: 610 Medical sciences Medicine
description: Background: Intracellular defense proteins, also referred to as restriction factors, are capable of interfering with different steps of the viral life cycle. Among these, we have shown that Tripartite motif 22 (TRIM22) suppresses basal as well as phorbol ester-induced HIV-1 long terminal repeat (LTR)-mediated transcription, independently of its E3 ubiquitin ligase activity, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) binding to the U3 region and Tat interaction with the TAR region of the HIV-1 LTR. As basal HIV-1 transcription is driven by the transcription factor specificity protein 1 (Sp1), we have investigated whether TRIM22 could interfere with Sp1-driven transcriptional activation of the HIV-1 LTR.   Findings: 293T cells, devoid of endogenous TRIM22 expression, were transfected with a TRIM22-expressing plasmid together with reporter plasmids driven by the HIV-1 LTR promoter either containing or lacking Sp1 binding sites or with reporter plasmids driven by non-viral promoter sequences either containing or lacking the three Sp1 binding sites from the HIV-1 LTR. These reporter assays showed that TRIM22 efficiently inhibited Sp1-driven transcription. Knocking down TRIM22 expression in the CD4+ SupT1 T cell line increased the replication of Sp1-dependent HIV-1 variants. TRIM22 did not interact with Sp1, but prevented binding of Sp1 to the HIV-1 promoter, as demonstrated in protein-DNA pull down and chromatin immunoprecipitation assays.   Conclusion: TRIM22 acts as a suppressor of basal HIV-1 LTR-driven transcription by preventing Sp1 binding to the HIV-1 promoter.
publisher: BioMed Central
date: 2015
type: Article
type: info:eu-repo/semantics/article
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/20004/1/12977_2015_Article_230.pdf
identifier: DOI:http://dx.doi.org/10.1186/s12977-015-0230-0
identifier: urn:nbn:de:bsz:16-heidok-200042
identifier:   Turrini, Filippo ; Marelli, Sara ; Kajaste-Rudnitski, Anna ; Lusic, Marina ; Van Lint, Carine ; Das, Atze T. ; Harwig, Alex ; Berkhout, Ben ; Vicenzi, Elisa  (2015) HIV-1 transcriptional silencing caused by TRIM22 inhibition of Sp1 binding to the viral promoter.  Retrovirology, 12 (104).  pp. 1-8.  ISSN 1742-4690     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/20004/
rights: info:eu-repo/semantics/openAccess
rights: Please see front page of the work (Sorry, Dublin Core plugin does not recognise license id)
language: eng