title: Polycomb group-mediated gene silencing mechanisms: stability versus flexibility.
abstract: Polycomb group (PcG) proteins are highly conserved chromatin factors that repress transcription of particular target genes in animals and plants. PcG proteins form multimeric complexes that act on their target genes through the regulation of post-translational histone modifications, the modulation of chromatin structure and chromosome organization. PcG proteins have long been considered as a cellular memory system that stably locks regulatory chromatin states for the whole lifespan of the organism. However, recent work on the genome-wide distribution of PcG components and their associated chromatin marks in vertebrate cells and Drosophila have challenged this view, revealing that PcG proteins confer dynamic transcriptional control of key developmental genes during cell differentiation and development.
authors: Institut de Génétique Humaine, CNRS UPR 1142, 141 rue de la Cardonille, Montpellier Cedex 5, France.
authors: Virginie
authors: V
authors: Roure
authors: Frédéric
authors: F
authors: Bantignies
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000235:genetics*; D002843:Chromatin / Q000235:genetics* / Q000502:physiology; D019175:DNA Methylation / Q000235:genetics / Q000502:physiology*; D004330:Drosophila; D020868:Gene Silencing / Q000502:physiology*; D006657:Histones / Q000378:metabolism; D008958:Models, Molecular; D046912:Multiprotein Complexes / Q000502:physiology*; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins / Q000737:chemistry / Q000502:physiology*
chemical_list: D002843:Chromatin; D006657:Histones; D046912:Multiprotein Complexes; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins