title: Runx Family Genes in Tissue Stem Cell Dynamics.
abstract: The Runx family genes play important roles in development and cancer, largely via their regulation of tissue stem cell behavior. Their involvement in two organs, blood and skin, is well documented. This review summarizes currently known Runx functions in the stem cells of these tissues. The fundamental core mechanism(s) mediated by Runx proteins has been sought; however, it appears that there does not exist one single common machinery that governs both tissue stem cells. Instead, Runx family genes employ multiple spatiotemporal mechanisms in regulating individual tissue stem cell populations. Such specific Runx requirements have been unveiled by a series of cell type-, developmental stage- or age-specific gene targeting studies in mice. Observations from these experiments revealed that the regulation of stem cells by Runx family genes turned out to be far more complex than previously thought. For instance, although it has been reported that Runx1 is required for the endothelial-to-hematopoietic cell transition (EHT) but not thereafter, recent studies clearly demonstrated that Runx1 is also needed during the period subsequent to EHT, namely at perinatal stage. In addition, Runx1 ablation in the embryonic skin mesenchyme eventually leads to complete loss of hair follicle stem cells (HFSCs) in the adult epithelium, suggesting that Runx1 facilitates the specification of skin epithelial stem cells in a cell extrinsic manner. Further in-depth investigation into how Runx family genes are involved in stem cell regulation is warranted.
authors.affiliation: Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore.|Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore.
authors.forename: Chelsia Qiuxia
authors.initials: CQ
authors.lastname: Wang
authors.affiliation: Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore.
authors.forename: Michelle Meng Huang
authors.initials: MM
authors.lastname: Mok
authors.affiliation: International Research Center for Medical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan.
authors.forename: Tomomasa
authors.initials: T
authors.lastname: Yokomizo
authors.affiliation: Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore.
authors.forename: Vinay
authors.initials: V
authors.lastname: Tergaonkar
authors.affiliation: Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore. csimo@nus.edu.sg.|International Research Center for Medical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan. csimo@nus.edu.sg.|Institute of Bioengineering and Nanotechnology, A*STAR, Singapore, Singapore. csimo@nus.edu.sg.|Department of Paediatrics, National University of Singapore, Singapore, Singapore. csimo@nus.edu.sg.
authors.forename: Motomi
authors.initials: M
authors.lastname: Osato
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D050657:Core Binding Factor alpha Subunits / Q000235:genetics* / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D018859:Hair Follicle / Q000378:metabolism / Q000502:physiology; D006801:Humans; D012867:Skin / Q000378:metabolism / Q000503:physiopathology; D013234:Stem Cells / Q000378:metabolism* / Q000502:physiology*
chemical_list: D050657:Core Binding Factor alpha Subunits
keywords: Aging; Conditional knockout mice; DNA damage repair; Fetal liver; Hair follicle stem cell; Hematopoietic stem cell; Hmga2; Leukemia; Niche; Perinatal; Runx; Skin cancer