PML protein organizes heterochromatin domains where it regulates histone H3.3 deposition by ATRX/DAXX.
Maintenance of chromatin homeostasis involves proper delivery of histone variants to the genome. The interplay between different chaperones regulating the supply of histone variants to distinct chromatin domains remains largely undeciphered. We report a role of promyelocytic leukemia (PML) protein in the routing of histone variant H3.3 to chromatin and in the organization of megabase-size heterochromatic PML-associated domains that we call PADs. Loss of PML alters the heterochromatic state of PADs by shifting the histone H3 methylation balance from K9me3 to K27me3. Loss of PML impairs deposition of H3.3 by ATRX and DAXX in PADs but preserves the H3.3 loading function of HIRA in these regions. Our results unveil an unappreciated role of PML in the large-scale organization of chromatin and demonstrate a PML-dependent role of ATRX/DAXX in the deposition of H3.3 in PADs. Our data suggest that H3.3 loading by HIRA and ATRX-dependent H3K27 trimethylation constitute mechanisms ensuring maintenance of heterochromatin when the integrity of these domains is compromised.
Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway.
Erwan
E
Delbarre
Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway.
Kristina
K
Ivanauskiene
Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway.
Jane
J
Spirkoski
Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway.
Akshay
A
Shah
Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway.
Kristin
K
Vekterud
Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway.
Jan Øivind
JØ
Moskaug
Department of Medical Biochemistry, Oslo University Hospital, 0027 Oslo, Norway.
Stig Ove
SO
Bøe
Department of Biochemistry and Molecular Biology, School of Biomedical Science, Monash University, Clayton, Victoria 3800, Australia.
Lee H
LH
Wong
Department of Oral Biology, University of Oslo, 0316 Oslo, Norway.
Thomas
T
Küntziger
Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway.|Norwegian Center for Stem Cell Research, Oslo University Hospital, 0027 Oslo, Norway.
Philippe
P
Collas
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D042002:Chromatin Assembly and Disassembly; D056970:Co-Repressor Proteins; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D036681:Fluorescence Recovery After Photobleaching; D005786:Gene Expression Regulation; D006570:Heterochromatin / Q000378:metabolism* / Q000648:ultrastructure; D006657:Histones / Q000235:genetics* / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics* / Q000378:metabolism; D008745:Methylation; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018832:Molecular Chaperones; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D009707:Nucleosomes / Q000378:metabolism* / Q000648:ultrastructure; D000071156:Promyelocytic Leukemia Protein / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D000075924:X-linked Nuclear Protein / Q000235:genetics* / Q000378:metabolism
D002352:Carrier Proteins; D056970:Co-Repressor Proteins; C491473:Daxx protein, mouse; D006570:Heterochromatin; D006657:Histones; D047908:Intracellular Signaling Peptides and Proteins; D018832:Molecular Chaperones; D009687:Nuclear Proteins; D009707:Nucleosomes; C513293:Pml protein, mouse; D000071156:Promyelocytic Leukemia Protein; C490462:Atrx protein, mouse; D000075924:X-linked Nuclear Protein