Hematopoietic tissues, as a playground of receptor tyrosine kinases of the PDGF-receptor family.
Three receptor tyrosine kinases of the PDGF receptor family (RTKP) that clustered within 1000 Kb of the mouse chromosome 5 constitute an interesting unit that are expressed in three distinct cell lineages essential for constructing hematopoietic tissues. Namely, the c-kit gene that is expressed in hematopoietic stem cells is flanked by pdgfr alpha and flk genes expressed respectively in stromal cells and vascular endothelial cells. In this article, we review our results on their expression in the embryonic hematopoietic tissues. We found that co-expression of Flkl and c-Kit was frequently detected either in vascular endothelial cells or hematopoietic cells in the early hematopoietic tissues. On the other hand, the three RTKPs are expressed in different cell lineages in the fetal liver. On the basis of this finding, we propose two modes of embryonic hematopoiesis; hematogenic angiopoiesis and hematopoiesis.
Department of Molecular Genetics, Faculty of Medicine, Kyoto University, Japan.
H
H
Yoshida
N
N
Takakura
M
M
Hirashima
H
H
Kataoka
K
K
Tsuchida
S
S
Nishikawa
S
S
Nishikawa
D000818:Animals; D004730:Endothelium, Vascular / Q000201:enzymology; D015870:Gene Expression; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000201:enzymology; D006413:Hematopoietic System / Q000201:enzymology*; D006801:Humans; D051379:Mice; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis*; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis*; D017978:Receptors, Growth Factor / Q000096:biosynthesis*; D017479:Receptors, Platelet-Derived Growth Factor / Q000096:biosynthesis*; D040262:Receptors, Vascular Endothelial Growth Factor; D017154:Stromal Cells / Q000201:enzymology
D017978:Receptors, Growth Factor; D019009:Proto-Oncogene Proteins c-kit; D020794:Receptor Protein-Tyrosine Kinases; D017479:Receptors, Platelet-Derived Growth Factor; D040262:Receptors, Vascular Endothelial Growth Factor