Suz12 silences large regions of the genome in a cell type-specific manner

Department of Pharmacology and the Genome Center, University of California-Davis, Davis, California 95616, USA.
Genome Research (Impact Factor: 14.63). 08/2006; 16(7):890-900. DOI: 10.1101/gr.5306606
Source: PubMed


Suz12 is a component of the Polycomb group complexes 2, 3, and 4 (PRC 2/3/4). These complexes are critical for proper embryonic development, but very few target genes have been identified in either mouse or human cells. Using a variety of ChIP-chip approaches, we have identified a large set of Suz12 target genes in five different human and mouse cell lines. Interestingly, we found that Suz12 target promoters are cell type specific, with transcription factors and homeobox proteins predominating in embryonal cells and glycoproteins and immunoglobulin-related proteins predominating in adult tumors. We have also characterized the localization of other components of the PRC complex with Suz12 and investigated the overall relationship between Suz12 binding and markers of active versus inactive chromatin, using both promoter arrays and custom tiling arrays. Surprisingly, we find that the PRC complexes can be localized to discrete binding sites or spread through large regions of the mouse and human genomes. Finally, we have shown that some Suz12 target genes are bound by OCT4 in embryonal cells and suggest that OCT4 maintains stem cell self-renewal, in part, by recruiting PRC complexes to certain genes that promote differentiation.

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Available from: Peggy J Farnham, Dec 18, 2013
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    • "The binding of Suz12 to wingless (Wnt1), a beta-catenin dependent developmental regulator and to the RNA polymerase II promoter (RNAPII), a housekeeping gene, served as positive and negative controls, respectively, in these experiments (Figure S2 in File S1) [21]. "
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    • "Purified DNA was taken for qPCR with primers for MYTD1, EIF3S10, hoxA2 or hoxD11.12 listed in Supplementary Table S1 (37,48). ChIP assays were repeated three to five times with qPCR performed in triplicate for each assay. "
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