GSE28162
L3MBTL2 protein acts in concert with PcG protein mediated monoubiquitination of H2A to establish a repressive chromatin structure [ChIP-Seq data].
Human MBT domain-containing protein L3MBTL2 was found to be an integral component of a protein complex that we termed Polycomb Repressive Complex 1-like 3 (PRC1L3) given the presence of the PcG proteins RING1, RING2 and PCGF6. L3MBTL2 binds chromatin in a histone modification-independent manner and is required for the repressive function of PRC1L3. PRC1L3 also contains E2F6 and CBX3, two factors with well-established functions in transcriptional repression. Genome-wide profiling identified several hundred genes that are simultaneously bound by L3MBTL2 and E2F6, preferentially around transcriptional start sites. Importantly, these genes are largely distinct from those targeted by other E2Fs or L3MBTL, another MBT-domain containing protein that interacts with RB1. H3K27 or H3K9 methylation, two chromatin modifications implicated in gene silencing, are not present on all L3MBTL2 target genes. L3MBTL2-specific RNAi results in altered target gene expression patterns and affects the differentiation program of hematopoietic cells. Our data suggest that repression of transcription via chromatin modulation, reflective of PRC1 function, can be achieved by multiple players and does not necessarily require the presence of histone lysine methylation marks. Overall design: 7 total ChIP-seq datasets; one L3MBTL2 dataset done in duplicate in K562 cells; one E2F6 dataset done in duplicate in K562 cells; one H3K27me3 replicate dataset in K562 cells.