title: The histone subcode: poly(ADP-ribose) polymerase-1 (Parp-1) and Parp-2 control cell differentiation by regulating the transcriptional intermediary factor TIF1beta and the heterochromatin protein HP1alpha.
abstract: Recent advances reveal emerging unique functions of poly(ADP-ribose) polymerase-1 (Parp-1) and Parp-2 in heterochromatin integrity and cell differentiation. However, the chromatin-mediated molecular and cellular events involved remain elusive. Here we describe specific physical and functional interactions of Parp-1 and Parp-2 with the transcriptional intermediary factor (TIF1beta) and the heterochromatin proteins (HP1) that affect endodermal differentiation. We show that Parp-2 binds to TIF1beta with high affinity both directly and through HP1alpha. Both partners colocalize at pericentric heterochromatin in primitive endoderm-like cells. Parp-2 also binds to HP1beta but not to HP1gamma. In contrast Parp-1 binds weakly to TIF1beta and HP1beta only. Both Parps selectively poly(ADP-ribosyl)ate HP1alpha. Using shRNA approaches, we provide evidence for distinct participation of both Parps in endodermal differentiation. Whereas Parp-2 and its activity are required for the relocation of TIF1beta to heterochromatic foci during primitive endodermal differentiation, Parp-1 and its activity modulate TIF1beta-HP1alpha association with consequences on parietal endodermal differentiation. Both Parps control TIF1beta transcriptional activity. In addition, this work identifies both Parps as new modulators of the HP1-mediated subcode histone.-Quénet, D., Gasser, V., Fouillen, L., Cammas, F., Sanglier-Cianferani, S., Losson, R., Dantzer, F. The histone subcode: poly(ADP-ribose) polymerase-1 (Parp-1) and Parp-2 control cell differentiation by regulating the transcriptional intermediary factor TIF1beta and the heterochromatin protein HP1alpha.
authors.affiliation: Département IDG, UMR7175, ESBS, Bld. S. Brant, 67412 Illkirch, France. fdantzer@esbs.u-strasbg.fr
authors.forename: Delphine
authors.initials: D
authors.lastname: Quénet
authors.forename: Véronique
authors.initials: V
authors.lastname: Gasser
authors.forename: Laetitia
authors.initials: L
authors.lastname: Fouillen
authors.forename: Florence
authors.initials: F
authors.lastname: Cammas
authors.forename: Sarah
authors.initials: S
authors.lastname: Sanglier-Cianferani
authors.forename: Régine
authors.initials: R
authors.lastname: Losson
authors.forename: Françoise
authors.initials: F
authors.lastname: Dantzer
mesh_terms: D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line; D000090266:Chromobox Protein Homolog 5; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004707:Endoderm / Q000166:cytology / Q000201:enzymology*; D006570:Heterochromatin / Q000378:metabolism*; D006801:Humans; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D000076183:Tripartite Motif-Containing Protein 28
chemical_list: C000715593:CBX1 protein, human; C000715594:CBX5 protein, human; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D006570:Heterochromatin; D012097:Repressor Proteins; D000090266:Chromobox Protein Homolog 5; C101116:TRIM28 protein, human; D000076183:Tripartite Motif-Containing Protein 28; C499320:PARP1 protein, human; C483041:PARP2 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases