title: Novel types and sites of histone modifications emerge as players in the transcriptional regulation contest.
abstract: N-terminal tails of histones are easily accessible outside of the nucleosomal core particle and post-translational modifications (PTMs) of these tails have been the focus of attention in the past 15-20 years. By recruiting (or excluding) specific readers, histone modifications can regulate chromatin dynamics and, by extension, DNA-dependent processes. However, until very recently, the direct impact of histone PTMs on nucleosome structure and thus on chromatin function has remained somewhat elusive. Recent findings of novel sites and types of histone PTMs located within the globular domain of histones and, in particular, on the lateral surface of the histone octamer have changed this. As a result of their structurally important location in close proximity to the DNA molecule, this new class of histone PTMs can have a direct impact on chromatin function. Depending on their precise position at the nucleosome lateral surface (e.g. near the DNA entry/exit sites or in the dyad region), histone PTMs can regulate nucleosome structure and/or stability differently. We review recent progress on how histone PTMs can influence DNA unwrapping and/or nucleosome disassembly and shed light on how these types of novel modifications contribute mechanistically to the regulation of transcriptional activity.
authors.affiliation: Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS UMR 7104 - Inserm U964, Université de Strasbourg, Illkirch, France.
authors.forename: Adam F
authors.initials: AF
authors.lastname: Kebede
authors.forename: Robert
authors.initials: R
authors.lastname: Schneider
authors.forename: Sylvain
authors.initials: S
authors.lastname: Daujat
mesh_terms: D004247:DNA / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D006657:Histones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D014158:Transcription, Genetic
chemical_list: D006657:Histones; D004247:DNA
keywords: DNA entry/exit sites; acetylation; chromatin; dyad axis; globular domain; lateral surface; methylation; nucleosome; transcription