title: The Drosophila polycomb protein interacts with nucleosomal core particles In vitro via its repression domain.
abstract: The proteins of the Polycomb group (PcG) are required for maintaining regulator genes, such as the homeotic selectors, stably and heritably repressed in appropriate developmental domains. It has been suggested that PcG proteins silence genes by creating higher-order chromatin structures at their chromosomal targets, thus preventing the interaction of components of the transcriptional machinery with their cis-regulatory elements. An unresolved issue is how higher order-structures are anchored at the chromatin base, the nucleosomal fiber. Here we show a direct biochemical interaction of a PcG protein-the Polycomb (PC) protein-with nucleosomal core particles in vitro. The main nucleosome-binding domain coincides with a region in the C-terminal part of PC previously identified as the repression domain. Our results suggest that PC, by binding to the core particle, recruits other PcG proteins to chromatin. This interaction could provide a key step in the establishment or regulation of higher-order chromatin structures.
authors.affiliation: ZMBH, University of Heidelberg, 69120 Heidelberg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Breiling
authors.forename: E
authors.initials: E
authors.lastname: Bonte
authors.forename: S
authors.initials: S
authors.lastname: Ferrari
authors.forename: P B
authors.initials: PB
authors.lastname: Becker
authors.forename: R
authors.initials: R
authors.lastname: Paro
mesh_terms: D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000378:metabolism; D004330:Drosophila; D029721:Drosophila Proteins; D006657:Histones / Q000378:metabolism*; D019476:Insect Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D009707:Nucleosomes / Q000378:metabolism*; D063150:Polycomb Repressive Complex 1; D017434:Protein Structure, Tertiary; D012097:Repressor Proteins / Q000378:metabolism*; D014357:Trypsin
chemical_list: D029721:Drosophila Proteins; D006657:Histones; D019476:Insect Proteins; D009707:Nucleosomes; C066770:Pc protein, Drosophila; D012097:Repressor Proteins; D004247:DNA; D063150:Polycomb Repressive Complex 1; D014357:Trypsin