Open AccessRole of Polycomb Group Proteins in the DNA Damage Response – A Reassessment
Author(s) -
Hollie Chandler,
Harshil Patel,
Richard D. Palermo,
Sharon Brookes,
Nik Matthews,
Gordon Peters
Publication year - 2014
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0102968
Subject(s) - polycomb group proteins , biology , chromatin immunoprecipitation , chromatin , dna , immunoprecipitation , dna damage , dna repair , microbiology and biotechnology , regulation of gene expression , gene , genetics , gene expression , repressor , promoter
A growing body of evidence suggests that Polycomb group (PcG) proteins, key regulators of lineage specific gene expression, also participate in the repair of DNA double-strand breaks (DSBs) but evidence for direct recruitment of PcG proteins at specific breaks remains limited. Here we explore the association of Polycomb repressive complex 1 (PRC1) components with DSBs generated by inducible expression of the Asi SI restriction enzyme in normal human fibroblasts. Based on immunofluorescent staining, the co-localization of PRC1 proteins with components of the DNA damage response (DDR) in these primary cells is unconvincing. Moreover, using chromatin immunoprecipitation and deep sequencing (ChIP-seq), which detects PRC1 proteins at common sites throughout the genome, we did not find evidence for recruitment of PRC1 components to Asi SI-induced DSBs. In contrast, the S2056 phosphorylated form of DNA-PKcs and other DDR proteins were detected at a subset of Asi SI sites that are predominantly at the 5′ ends of transcriptionally active genes. Our data question the idea that PcG protein recruitment provides a link between DSB repairs and transcriptional repression.