title: Modulation of heterochromatin protein 1 dynamics in primary Mammalian cells.
abstract: Heterochromatin protein 1 (HP1beta), a key component of condensed DNA, is strongly implicated in gene silencing and centromeric cohesion. Heterochromatin has been considered a static structure, stabilizing crucial aspects of nuclear organization and prohibiting access to transcription factors. We demonstrate here, by fluorescence recovery after photobleaching, that a green fluorescent protein-HP1beta fusion protein is highly mobile within both the euchromatin and heterochromatin of ex vivo resting murine T cells. Moreover, T cell activation greatly increased this mobility, indicating that such a process may facilitate (hetero)chromatin remodeling and permit access of epigenetic modifiers and transcription factors to the many genes that are consequently derepressed.
authors.affiliation: CSC Gene Control Mechanisms and Disease Group, Division of Medicine, Imperial College School of Medicine, Hammersmith Campus, Du Cane Road, London W12 ONN, UK. r.festenstein@ic.ac.uk
authors.forename: Richard
authors.initials: R
authors.lastname: Festenstein
authors.forename: Stamatis N
authors.initials: SN
authors.lastname: Pagakis
authors.forename: Kyoko
authors.initials: K
authors.lastname: Hiragami
authors.forename: Debbie
authors.initials: D
authors.lastname: Lyon
authors.forename: Alain
authors.initials: A
authors.lastname: Verreault
authors.forename: Belaid
authors.initials: B
authors.lastname: Sekkali
authors.forename: Dimitris
authors.initials: D
authors.lastname: Kioussis
mesh_terms: D000818:Animals; D001665:Binding Sites; D002478:Cells, Cultured; D000090266:Chromobox Protein Homolog 5; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D019281:Dimerization; D022041:Euchromatin / Q000378:metabolism*; D005453:Fluorescence; D036681:Fluorescence Recovery After Photobleaching; D006570:Heterochromatin / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D007700:Kinetics; D008213:Lymphocyte Activation; D008745:Methylation; D051379:Mice; D018613:Microscopy, Confocal; D013601:T-Lymphocytes / Q000378:metabolism*
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D022041:Euchromatin; D006570:Heterochromatin; D006657:Histones; D000090266:Chromobox Protein Homolog 5