title: Characterization of GATA-1(+) hemangioblastic cells in the mouse embryo.
abstract: Hemangioblasts are thought to be one of the sources of hematopoietic progenitors, yet little is known about their localization and fate in the mouse embryo. We show here that a subset of cells co-expressing the hematopoietic marker GATA-1 and the endothelial marker VE-cadherin localize on the yolk sac blood islands at embryonic day 7.5. Clonal analysis demonstrated that GATA-1(+) cells isolated from E7.0-7.5 embryos include a common precursor for hematopoietic and endothelial cells. Moreover, this precursor possesses primitive and definitive hematopoietic bipotential. By using a transgenic complementation rescue approach, GATA-1(+) cell-derived progenitors were selectively restored in Runx1-deficient mice. In the rescued mice, definitive erythropoiesis was recovered but the rescued progenitors did not display multilineage hematopoiesis or intra-aortic hematopoietic clusters. These results provide evidence of the presence of GATA-1(+) hemangioblastic cells in the extra-embryonic region and also their functional contribution to hematopoiesis in the embryo.
authors.affiliation: Institute of Basic Medical Sciences and Center for TARA, University of Tsukuba, Tsukuba, Japan.
authors.forename: Tomomasa
authors.initials: T
authors.lastname: Yokomizo
authors.forename: Satoru
authors.initials: S
authors.lastname: Takahashi
authors.forename: Naomi
authors.initials: N
authors.lastname: Mochizuki
authors.forename: Takashi
authors.initials: T
authors.lastname: Kuroha
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Ema
authors.forename: Asami
authors.initials: A
authors.lastname: Wakamatsu
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Shimizu
authors.forename: Osamu
authors.initials: O
authors.lastname: Ohneda
authors.forename: Motomi
authors.initials: M
authors.lastname: Osato
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Okada
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Komori
authors.forename: Minetaro
authors.initials: M
authors.lastname: Ogawa
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Nishikawa
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Ito
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D001011:Aorta / Q000378:metabolism; D015820:Cadherins / Q000378:metabolism*; D019070:Cell Lineage; D050676:Core Binding Factor Alpha 2 Subunit / Q000235:genetics; D050982:GATA1 Transcription Factor / Q000235:genetics* / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D049452:Green Fluorescent Proteins / Q000737:chemistry; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D017493:Leukocyte Common Antigens / Q000096:biosynthesis; D051379:Mice; D008822:Mice, Transgenic; D008954:Models, Biological; D013234:Stem Cells / Q000166:cytology; D019076:Transgenes; D000099152:Cadherin 5
chemical_list: D015703:Antigens, CD; D015820:Cadherins; D050676:Core Binding Factor Alpha 2 Subunit; D050982:GATA1 Transcription Factor; D049452:Green Fluorescent Proteins; D017493:Leukocyte Common Antigens; D000099152:Cadherin 5; C494689:Gata1 protein, mouse; C493726:Runx1 protein, mouse