The cohesin-associated protein Wapal is required for proper Polycomb-mediated gene silencing

abstract: ...Background The cohesin complex consists of multiple core subunits that play critical roles in mitosis and transcriptional regulation. The cohesin-associated protein Wapal plays a central role in off-loading cohesin to facilitate sister chromatid separation, but its role in regulating mammalian gene expression is not understood. We used embryonic stem cells as a model, given that the well-defined transcriptional regulatory circuits were established through master transcription factors and epigenetic pathways that regulate their ability to maintain a pluripotent state. Results RNAi-mediated depletion of Wapal causes a loss of pluripotency, phenocopying loss of core cohesin subunits. Using chromatin immunoprecipitation coupled with next-generation sequencing (ChIP-seq), we determine that Wapal occupies genomic sites distal to genes in combination with CTCF and core cohesin subunits such as Rad21. Interestingly, genomic sites occupied by Wapal appear enriched for cohesin, implying that Wapal does not off-load cohesin at regions it occupies. Wapal depletion induces derepression of Polycomb group (PcG) target genes without altering total levels of Polycomb-mediated histone modifications, implying that PcG enzymatic activity is preserved. By integrating ChIP-seq and gene expression changes data, we identify that Wapal binding is enriched at the promoters of PcG-silenced genes and is required for proper Polycomb repressive complex 2 (PRC2) recruitment. Lastly, we demonstrate that Wapal is required for the interaction of a distal cis -regulatory element (CRE) with the c - Fos promoter. Conclusions Collectively, this work indicates that Wapal plays a critical role in silencing of PcG target genes through the interaction of distal CREs with promoters. Electronic supplementary material The online version of this article (doi:10.1186/s13072-016-0063-7) contains supplementary material, which is available to authorized users.

...Epigenetics Chromatin Epigenetics Chromatin Epigenetics & Chromatin 1756-8935 BioMed Central London 27087855 4832553 63 10.1186/s13072-016-0063-7 Research The cohesin-associated protein Wapal is required for proper Polycomb-mediated gene silencing Stelloh Cary Cary.Stelloh@BCW.edu Reimer Michael H. mhreimer@mcw.edu Pulakanti Kirthi Kirthi.Pulakanti@BCW.edu Blinka Steven sblinka@mcw.edu Peterson Jonathan Jonathan.Peterson@uphs.upenn.edu Pinello Luca lucapinello@gmail.com Jia Shuang sjia@mcw.edu

... and transcriptional regulation. The cohesin-associated protein Wapal plays a central role in off-loading cohesin to facilitate sister chromatid separation, but its role in regulating mammalian gene expression is not understood. We used embryonic stem cells as a model, given that the well-defined transcriptional regulatory circuits were established through master transcription factors and epigenetic pathways that regulate their ability to maintain a pluripotent state. Results RNAi-mediated depletion of Wapal causes a loss of pluripotency, phenocopying loss of core cohesin subunits. Using chromatin immunoprecipitation coupled with next-generation sequencing (ChIP-seq), we determine that Wapal occupies genomic sites distal to genes in combination with CTCF and core cohesin subunits such as Rad21. Interestingly, genomic sites occupied by Wapal appear enriched for cohesin, implying that Wapal does not off-load cohesin at regions it occupies. Wapal depletion induces derepression of Polycomb group (PcG) target genes without altering total levels of Polycomb-mediated histone modifications, implying that PcG enzymatic activity is preserved. By integrating ChIP-seq and gene expression changes data, we identify that Wapal binding is enriched at the promoters of PcG-silenced genes and is required for proper Polycomb repressive complex 2 (PRC2) recruitment. Lastly, we demonstrate that Wapal is required for the interaction of a distal cis -regulatory element (CRE) with the c - Fos promoter. Conclusions Collectively, this work indicates that Wapal plays a critical role in silencing of PcG target genes through the interaction of distal CREs with promoters. Electronic supplementary material The online version of this article (doi:10.1186/s13072-016-0063-7) contains supplementary material, which is available to authorized users. Keywords Cohesin complex Epigenetics Embryonic stem cells Wapal Polycomb complex http://dx.doi.org/10.13039/100000048 American Cancer Society IRG86-004 Rao Sridhar

... chromatid cohesion during mitosis, ensuring proper genomic segregation [ 4 ]. In mitosis, the core cohesin subunits Smc1a, Smc3, and Rad21 are loaded onto sister chromatids by Nipbl in early G1/late telophase and off-loaded starting in prophase by Wapal [ 5 , 6 ]. While the function of core cohesin subunits and accessory proteins (Nipbl, Wapal) are well established during mitosis, Wapals role during transcriptional regulation remains less well defined. The core cohesin subunits facilitate interactions between genes and distal cis -regulatory elements by looping-out the intervening chromatin segment [ 2 4 , 7 ]. In embryonic stem cells (ESCs), the majority of cohesin-binding sites are co-occupied by CTCF, but a minority of cohesin-binding sites represent transcriptional enhancers [ 2 , 8 10 ]. Depletion of cohesin core subunits by RNA interferences (RNAi) in ESCs causes differentiation secondary to either transcriptional or cell-cycle changes [ 2 , 8 , 11 ]. Whether Wapal participates in gene

infinome is a free SNP search engine. Link your 23andMe account for personalized reports.

Gene: WAPAL - wings apart-like homolog (Drosophila) - (NCBI)

Protein : 4k6j

Images from Open Access Papers

Association Studies

Search Results from Open Access Papers