Endomucin is expressed in embryonic dorsal aorta and is able to inhibit cell adhesion.
Recent studies have suggested the existence of progenitors common to hematopoietic and endothelial cells, called hemangioblasts, in, for instance, embryonic dorsal aorta. To identify a membrane-bound or secretory molecule regulating early hematopoiesis, we screened a cDNA library from dorsal aortas of embryonic day (E) 10.5 mice by a signal sequence trap method and obtained a clone encoding a sialoprotein, endomucin-1. Immunohistochemistry revealed that the endomucin-1 transcript was specifically expressed in the endothelial cells of dorsal aorta of E10.5 mouse embryo. Overexpression of endomucin-1 strongly inhibited adhesion and aggregation of cells, including cultured endothelial cells from E10.5 dorsal aorta. These data suggest that endomucin-1 may play a role in detachment of hematopoietic cells from endothelium during early hematopoiesis.
Ueno
M
M
Department of Cell Fate Modulation, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1, Honjo, Kumamoto 860-0811, Japan.
Igarashi
K
K
Kimura
N
N
Okita
K
K
Takizawa
M
M
Nobuhisa
I
I
Kojima
T
T
Kitamura
T
T
Samulowitz
U
U
Vestweber
D
D
Shimomura
T
T
Suda
T
T
Nakashima
K
K
Taga
T
T
D000595:Amino Acid Sequence; D000818:Animals; D001011:Aorta / Q000166:cytology / Q000378:metabolism; D001483:Base Sequence; D002448:Cell Adhesion / Q000502:physiology*; D002449:Cell Aggregation / Q000502:physiology; D018076:DNA, Complementary / Q000032:analysis; D004622:Embryo, Mammalian / Q000378:metabolism; D004730:Endothelium, Vascular / Q000378:metabolism / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000502:physiology; D051379:Mice; D008969:Molecular Sequence Data; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000032:analysis; D012333:RNA, Messenger / Q000235:genetics; D016415:Sequence Alignment; D012795:Sialoglycoproteins / Q000096:biosynthesis* / Q000502:physiology
D018076:DNA, Complementary; C498985:Emcn protein, mouse; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012333:RNA, Messenger; D012795:Sialoglycoproteins