title: SUMOylation promotes de novo targeting of HP1α to pericentric heterochromatin.
abstract: HP1 enrichment at pericentric heterochromatin is considered important for centromere function. Although HP1 binding to H3K9me3 can explain its accumulation at pericentric heterochromatin, how it is initially targeted there remains unclear. Here, in mouse cells, we reveal the presence of long nuclear noncoding transcripts corresponding to major satellite repeats at the periphery of pericentric heterochromatin. Furthermore, we find that major transcripts in the forward orientation specifically associate with SUMO-modified HP1 proteins. We identified this modification as SUMO-1 and mapped it in the hinge domain of HP1α. Notably, the hinge domain and its SUMOylation proved critical to promote the initial targeting of HP1α to pericentric domains using de novo localization assays, whereas they are dispensable for maintenance of HP1 domains. We propose that SUMO-HP1, through a specific association with major forward transcript, is guided at the pericentric heterochromatin domain to seed further HP1 localization.
authors.affiliation: Institut Curie, Centre de recherche, Paris, France.
authors.forename: Christèle
authors.initials: C
authors.lastname: Maison
authors.forename: Delphine
authors.initials: D
authors.lastname: Bailly
authors.forename: Danièle
authors.initials: D
authors.lastname: Roche
authors.forename: Rocio
authors.initials: R
authors.lastname: Montes de Oca
authors.forename: Aline V
authors.initials: AV
authors.lastname: Probst
authors.forename: Isabelle
authors.initials: I
authors.lastname: Vassias
authors.forename: Florent
authors.initials: F
authors.lastname: Dingli
authors.forename: Bérengère
authors.initials: B
authors.lastname: Lombard
authors.forename: Damarys
authors.initials: D
authors.lastname: Loew
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Quivy
authors.forename: Geneviève
authors.initials: G
authors.lastname: Almouzni
mesh_terms: D000818:Animals; D002503:Centromere / Q000378:metabolism; D000090266:Chromobox Protein Homolog 5; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D006570:Heterochromatin / Q000378:metabolism*; D051379:Mice; D017434:Protein Structure, Tertiary; D012313:RNA; D012091:Repetitive Sequences, Nucleic Acid; D058207:Sumoylation
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D006570:Heterochromatin; D000090266:Chromobox Protein Homolog 5; D012313:RNA