title: Zinc-finger transcription factor Gfi-1: versatile regulator of lymphocytes, neutrophils and hematopoietic stem cells.
abstract: OBJECTIVE
  Gfi-1, originally identified as a transcriptional repressor in lymphoid cells, is now recognized to have essential, independent functions in neutrophil maturation and hematopoietic stem cell biology. Here we review recent studies pertaining to Gfi-1 and its cell context specific functions in hematopoietic development.
  
  
  RESULTS
  Progress in mapping the precise timing of requirements for myeloid transcription factors during hematopoietic development reveals a more refined picture of their sequence of action. We contrast Gfi-1's role in neutrophil development with PU.1, C/EBPalpha, and C/EBPepsilon. Gfi-1 has been found to be a major regulator of adult hematopoietic stem cells. It is required for restricting the proliferation of hematopoietic stem cells and maintaining their functional integrity. We discuss its role and compare its function with that of other regulators recently implicated in the biology of hematopoietic stem cells.
  
  
  CONCLUSIONS
  Considerable progress has been made in understanding Gfi-1's context-sensitive roles at defined stages of hematopoietic differentiation.
authors.affiliation: Division of Hematology/Oncology, Children's Hospital, Dana Farber Cancer Institute, Boston, Massachusetts, USA. hock.hanno@mgh.harvard.edu
authors.forename: Hanno
authors.initials: H
authors.lastname: Hock
authors.forename: Stuart H
authors.initials: SH
authors.lastname: Orkin
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006412:Hematopoietic Stem Cells / Q000502:physiology*; D006801:Humans; D008214:Lymphocytes / Q000502:physiology*; D038042:Myelopoiesis / Q000502:physiology*; D009504:Neutrophils / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; C498275:GFI1 protein, human; D014157:Transcription Factors