Runx1 expression marks long-term repopulating hematopoietic stem cells in the midgestation mouse embryo.
Hematopoietic stem cells (HSCs) are first found in the aorta-gonad-mesonephros region and vitelline and umbilical arteries of the midgestation mouse embryo. Runx1 (AML1), the DNA binding subunit of a core binding factor, is required for the emergence and/or subsequent function of HSCs. We show that all HSCs in the embryo express Runx1. Furthermore, HSCs in Runx1(+/-) embryos are heterogeneous and include CD45(+) cells, endothelial cells, and mesenchymal cells. Comparison with wild-type embryos showed that the distribution of HSCs among these various cell populations is sensitive to Runx1 dosage. These data provide the first morphological description of embryonic HSCs and contribute new insight into their cellular origin.
North
Trista E
TE
Department of Biochemistry, Dartmouth Medical School, Hanover, NH 03755, USA.
de Bruijn
Marella F T R
MF
Stacy
Terryl
T
Talebian
Laleh
L
Lind
Evan
E
Robin
Catherine
C
Binder
Michael
M
Dzierzak
Elaine
E
Speck
Nancy A
NA
D000818:Animals; D015415:Biomarkers / Q000032:analysis; D019070:Cell Lineage; D050676:Core Binding Factor Alpha 2 Subunit; D004268:DNA-Binding Proteins / Q000032:analysis* / Q000235:genetics / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000166:cytology*; D004730:Endothelium, Vascular / Q000737:chemistry / Q000196:embryology; D018628:Gene Dosage; D005865:Gestational Age; D006412:Hematopoietic Stem Cells / Q000737:chemistry* / Q000145:classification; D016130:Immunophenotyping; D017493:Leukocyte Common Antigens / Q000737:chemistry; D008648:Mesoderm / Q000737:chemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D011518:Proto-Oncogene Proteins; D014157:Transcription Factors / Q000032:analysis* / Q000235:genetics / Q000378:metabolism*
D015415:Biomarkers; D050676:Core Binding Factor Alpha 2 Subunit; D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; C493726:Runx1 protein, mouse; D014157:Transcription Factors; D017493:Leukocyte Common Antigens