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Psip1/Ledgf p75 restrains Hox gene expression by recruiting both trithorax and polycomb group proteins.

ABSTRACT: Trithorax and polycomb group proteins are generally thought to antagonize one another. The trithorax family member MLL (myeloid/lymphoid or mixed-lineage leukemia) is presumed to activate Hox expression, counteracting polycomb-mediated repression. PC4 and SF2 interacting protein 1 (PSIP1)/p75, also known as LEDGF, whose PWWP domain binds to H3K36me3, interacts with MLL and tethers MLL fusion proteins to HOXA9 in leukaemias. Here we show, unexpectedly, that Psip1/p75 regulates homeotic genes by recruiting not only MLL complexes, but also the polycomb group protein Bmi1. In Psip1(-/-) cells binding of Mll1/2, Bmi1 and the co-repressor Ctbp1 at Hox loci are all abrogated and Hoxa and Hoxd mRNA expression increased. Our data not only reveal a potential mechanism of action for Psip1 in the regulation of Hox genes but also suggest an unexpected interplay between proteins usually considered as transcriptional activators and repressors.

SUBMITTER: Pradeepa MM

PROVIDER: S-EPMC4132756 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Psip1/p75 restrains Hox gene expression by recruiting both trithorax and polycomb group proteins

Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series

2014-06-27 | E-GEOD-49182 | biostudies-arrayexpress

Psip1/p75 restrains Hox gene expression by recruiting both trithorax and polycomb group proteins

Project description:This SuperSeries is composed of the SubSeries listed below.

2014-06-27 | GSE49182 | GEO

Psip1/p75 restrains Hox gene expression by recruiting both trithorax and polycomb group proteins

Project description:Psip1/p75 restrains Hox gene expression by recruiting both trithorax and polycomb group proteins

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Role of PSIP1/LEDGF/p75 in lentiviral infectivity and integration targeting.

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Targeted editing of the PSIP1 gene encoding LEDGF/p75 protects cells against HIV infection.

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Project description:Menin binding pattern in WT and Psip1 KO MEFs Menin occupancy is studied over Hox genes

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Project description:Psip1/p75 binds to Hox genes and colocalizes with Mll1 and in Psip1 KO MEFs Mll1 occupancy is reduced over Hox genes

2014-06-27 | GSE49179 | GEO