title: H1-nucleosome interactions and their functional implications.
abstract: Linker histones are three domain proteins and consist of a structured (globular) domain, flanked by two likely non-structured NH2- and COOH-termini. The binding of the linker histones to the nucleosome was characterized by different methods in solution. Apparently, the globular domain interacts with the linker DNA and the nucleosome dyad, while the binding of the large and rich in lysines COOH-terminus results in "closing" the linker DNA of the nucleosome and the formation of the "stem" structure. What is the mode of binding of the linker histones within the chromatin fiber remains still elusive. Nonetheless, it is clear that linker histones are essential for both the assembly and maintenance of the condensed chromatin fiber. Interestingly, linker histones are post-translationally modified and how this affects both their binding to chromatin and functions is now beginning to emerge. In addition, linker histones are highly mobile in vivo, but not in vitro. No explanation of this finding is reported for the moment. The higher mobility of the linker histones should, however, have strong impact on their function. Linker histones plays an important role in gene expression regulation and other chromatin related process and their function is predominantly regulated by their posttranslational modifications. However, the detailed mechanism how the linker histones do function remains still not well understood despite numerous efforts. Here we will summarize and analyze the data on the linker histone binding to the nucleosome and the chromatin fiber and will discuss its functional consequences.
authors.affiliation: Université de Grenoble Alpes/CNRS, Laboratoire Interdisciplinaire de Physique, UMR 5588, 140 rue de la Physique, B.P. 87, St. Martin d'Heres, F-38402, France. Electronic address: Jan.Bednar@ujf-grenoble.fr.
authors.forename: Jan
authors.initials: J
authors.lastname: Bednar
authors.affiliation: Equipe labellisée Ligue contre le Cancer, Département de Génomique Fonctionnelle et Cancer, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), UDS, CNRS, INSERM, 1 rue Laurent Fries, B.P. 10142, 67404 Illkirch Cedex, France.
authors.forename: Ali
authors.initials: A
authors.lastname: Hamiche
authors.affiliation: INSERM/UJF, Institut Albert Bonniot, U823, Site Santé-BP 170, 38042 Grenoble Cedex 9, France.
authors.forename: Stefan
authors.initials: S
authors.lastname: Dimitrov
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D042002:Chromatin Assembly and Disassembly; D005786:Gene Expression Regulation; D006657:Histones / Q000737:chemistry / Q000502:physiology*; D006801:Humans; D008969:Molecular Sequence Data; D009707:Nucleosomes / Q000502:physiology*
chemical_list: D006657:Histones; D009707:Nucleosomes
keywords: Gene expression regulation; Linker histone; Linker histone binding; Linker histone subtypes