Epigenetics & Chromatin

Publisher: BioMed Central

Journal description

Current impact factor: 4.46

Impact Factor Rankings

2015 Impact Factor Available summer 2015
2013 / 2014 Impact Factor 4.462
2012 Impact Factor 4.19
2011 Impact Factor 4.462
2010 Impact Factor 4.731

Impact factor over time

Impact factor
Year

Additional details

5-year impact 4.18
Cited half-life 2.60
Immediacy index 1.11
Eigenfactor 0.00
Article influence 2.24
Website
Other titles Epigenetics and chromatin
ISSN 1756-8935
OCLC 263688252
Material type Document, Periodical, Internet resource
Document type Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

BioMed Central

  • Pre-print
    • Author can archive a pre-print version
  • Post-print
    • Author can archive a post-print version
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    • Publisher's version/PDF may be used
    • Eligible UK authors may deposit in OpenDepot
    • Creative Commons Attribution License
    • Copy of License must accompany any deposit.
    • All titles are open access journals
    • 'BioMed Central' is an imprint of 'Springer Verlag (Germany)'
  • Classification
    ‚Äč green

Publications in this journal

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The small non-histone protein Heterochromatin protein 1a (HP1a) plays a vital role in packaging chromatin, most notably in forming constitutive heterochromatin at the centromeres and telomeres. A second major chromatin regulating system is that of the Polycomb/trithorax groups of genes which, respectively, maintain the repressed/activated state of euchromatin. Recent analyses suggest they affect the expression of a multitude of genes, beyond the homeotics whose alteration in expression lead to their initial discovery. Our data suggest that early in Drosophila development, HP1a collaborates with the Polycomb/trithorax groups of proteins to regulate gene expression and that the two chromatin systems do not act separately as convention describes. HP1a affects the levels of both the Polycomb complexes and RNA polymerase II at promoters, as assayed by chromatin immunoprecipitation analysis. Deposition of both the repressive (H3K27me3) and activating (H3K4me3) marks promoted by the Polycomb/trithorax group genes at gene promoters is affected. Additionally, depending on which parent contributes the null mutation of the HP1a gene, the levels of the H3K27me3 and H3K9me3 silencing marks at both promoters and heterochromatin are different. Changes in levels of the H3K27me3 and H3K9me3 repressive marks show a mostly reciprocal nature. The time around the mid-blastula transition, when the zygotic genome begins to be actively transcribed, appears to be a transition/decision point for setting the levels. We find that HP1a, which is normally critical for the formation of constitutive heterochromatin, also affects the generation of the epigenetic marks of the Polycomb/trithorax groups of proteins, chromatin modifiers which are key to maintaining gene expression in euchromatin. At gene promoters, deposition of both the repressive H3K27me3 and activating H3K4me3 marks of histone modifications shows a dependence on HP1a. Around the mid-blastula transition, when the zygotic genome begins to be actively transcribed, a pivotal decision for the level of silencing appears to take place. This is also when the embryo organizes its genome into heterochromatin and euchromatin. A balance between the HP1a and Polycomb group silencing systems appears to be set for the chromatin types that each system will primarily regulate.
    Epigenetics & Chromatin 12/2015; 8(1):17. DOI:10.1186/s13072-015-0010-z
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    [Show abstract] [Hide abstract]
    ABSTRACT: The number of different assays that has been published to study DNA methylation is extensive, complemented by recently described assays that test modifications of cytosine other than the most abundant 5-methylcytosine (5mC) variant. In this review, we describe the considerations involved in choosing how to study 5mC throughout the genome, with an emphasis on the common application of testing for epigenetic dysregulation in human disease. While microarray studies of 5mC continue to be commonly used, these lack the additional qualitative information from sequencing-based approaches that is increasingly recognized to be valuable. When we test the representation of functional elements in the human genome by several current assay types, we find that no survey approach interrogates anything more than a small minority of the nonpromoter cis-regulatory sites where DNA methylation variability is now appreciated to influence gene expression and to be associated with human disease. However, whole-genome bisulphite sequencing (WGBS) adds a substantial representation of loci at which DNA methylation changes are unlikely to be occurring with transcriptional consequences. Our assessment is that the most effective approach to DNA methylation studies in human diseases is to use targeted bisulphite sequencing of the cis-regulatory loci in a cell type of interest, using a capture-based or comparable system, and that no single design of a survey approach will be suitable for all cell types.
    Epigenetics & Chromatin 01/2015; 8:5. DOI:10.1186/1756-8935-8-5
  • Epigenetics & Chromatin 01/2015; DOI:10.1186/1756-8935-8-4