title: Role of the polycomb group proteins in hematopoietic stem cells.
abstract: Polycomb group (PcG) proteins play a role in the transcriptional repression of genes through histone modifications. Recent studies have clearly demonstrated that PcG proteins are required for the maintenance of embryonic as well as a broad range of adult stem cells, including hematopoietic stem cells (HSCs). PcG proteins maintain the self-renewal capacity of HSCs by repressing tumor suppressor genes and keep differentiation programs poised for activation in HSCs by repressing a cohort of hematopoietic developmental regulator genes via bivalent chromatin domains. Enforced expression of one of the PcG genes, Bmi1, augments the self-renewal capacity of HSCs. PcG proteins also maintain redox homeostasis to prevent premature loss of HSCs. These findings established PcG proteins as essential regulators of HSCs and underscored epigenetics as a new field of HSC research. In this review, we focus on the role of PcG proteins in the epigenetic regulation of the self-renewal capacity and multipotency of HSCs.
authors.affiliation: Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Konuma
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Oguro
authors.forename: Atsushi
authors.initials: A
authors.lastname: Iwama
mesh_terms: D000818:Animals; D002843:Chromatin / Q000378:metabolism; D047108:Embryonic Development / Q000502:physiology*; D044127:Epigenesis, Genetic / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D006706:Homeostasis / Q000502:physiology; D051379:Mice; D010084:Oxidation-Reduction; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins / Q000172:deficiency / Q000378:metabolism* / Q000502:physiology
chemical_list: D002843:Chromatin; D006657:Histones; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins