An amendment to this paper has been published and can be accessed via a link at the top of the paper.
View Article and Find Full Text PDFChromatin modifications regulate genome function by recruiting proteins to the genome. However, the protein composition at distinct chromatin modifications has yet to be fully characterized. In this study, we used natural protein domains as modular building blocks to develop engineered chromatin readers (eCRs) selective for DNA methylation and histone tri-methylation at H3K4, H3K9 and H3K27 residues.
View Article and Find Full Text PDFDNA methylation is a prevalent epigenetic modification involved in transcriptional regulation and essential for mammalian development. While the genome-wide distribution of this mark has been studied to great detail, the mechanisms responsible for its correct deposition, as well as the cause for its aberrant localization in cancers, have not been fully elucidated. Here, we have compared the activity of individual DNMT3A isoforms in mouse embryonic stem and neuronal progenitor cells and report that these isoforms differ in their genomic binding and DNA methylation activity at regulatory sites.
View Article and Find Full Text PDFDespite progress in mechanistic understanding of the RNA interference (RNAi) pathways, the subcellular sites of RNA silencing remain under debate. Here we show that loading of lipid-transfected siRNAs and endogenous microRNAs (miRNA) into RISC (RNA-induced silencing complexes), encounter of the target mRNA, and Ago2-mediated mRNA slicing in mammalian cells are nucleated at the rough endoplasmic reticulum (rER). Although the major RNAi pathway proteins are found in most subcellular compartments, the miRNA- and siRNA-loaded Ago2 populations co-sediment almost exclusively with the rER membranes, together with the RISC loading complex (RLC) factors Dicer, TAR RNA binding protein (TRBP) and protein activator of the interferon-induced protein kinase (PACT).
View Article and Find Full Text PDF