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Primer binding site-dependent restriction of murine leukemia virus requires HP1 binding by TRIM28.

ABSTRACT: TRIM28 is a transcriptional corepressor which is required for primer binding site (PBS)-dependent restriction of murine leukemia virus (MLV) replication in embryonic stem and embryonic carcinoma (EC) cells. PBS-dependent restriction of MLV leads to transcriptional silencing of the integrated provirus and has been shown to correlate with TRIM28-mediated recruitment of HP1 to the silenced loci. Here we show, using a cell line with a point mutation in the HP1 binding domain of TRIM28, that interaction with HP1 is absolutely required for the PBS-dependent restriction of MLV in the F9 EC cell line.

SUBMITTER: Wolf D

PROVIDER: S-EPMC2293057 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Primer binding site-dependent restriction of murine leukemia virus requires HP1 binding by TRIM28.

Wolf Daniel D Cammas Florence F Losson Régine R Goff Stephen P SP

Journal of virology 20080220 9

TRIM28 is a transcriptional corepressor which is required for primer binding site (PBS)-dependent restriction of murine leukemia virus (MLV) replication in embryonic stem and embryonic carcinoma (EC) cells. PBS-dependent restriction of MLV leads to transcriptional silencing of the integrated provirus and has been shown to correlate with TRIM28-mediated recruitment of HP1 to the silenced loci. Here we show, using a cell line with a point mutation in the HP1 binding domain of TRIM28, that interact ...[more]

PMID: 18287239

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