Embryonic expression of a haematopoietic growth factor encoded by the Sl locus and the ligand for c-kit.
Mice carrying mutations at the W (Dominant white spotting) and Sl (Steel) loci develop abnormalities in three independent systems: neural crest-derived melanocytes, primordial germ cells and haematopoietic stem cells. Consequently, homozygotes of viable mutant alleles have white coats and are sterile and severely anaemic. Tissue recombination studies predict that the W gene is expressed cell autonomously, whereas the product of the Sl locus affects the microenvironment in which the stem cells migrate, proliferate and differentiate. The W locus encodes the protoncogene c-kit, a member of the tyrosine kinase receptor family. The haematopoietic growth factor SCF (stem cell factor) has been identified as the product of the Sl locus and a ligand for c-kit. Here, we report that SCF is expressed during embryogenesis in cells associated with both the migratory pathways and homing sites of melanoblasts, germ cells and haematopoietic stem cells. Both SCF and c-kit are also expressed in a variety of other tissues, including the brain and spinal cord, suggesting that the receptor-ligand system has additional roles in embryogenesis.
Department of Cell Biology, Vanderbilt University Medical School, Nashville, Tennessee 37232-2172.
Y
Y
Matsui
K M
KM
Zsebo
B L
BL
Hogan
D000818:Animals; D001842:Bone and Bones / Q000196:embryology / Q000378:metabolism; D001921:Brain / Q000196:embryology / Q000378:metabolism; D004622:Embryo, Mammalian / Q000378:metabolism*; D015870:Gene Expression; D005854:Germ Cells / Q000378:metabolism; D016298:Hematopoietic Cell Growth Factors / Q000235:genetics* / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D008099:Liver / Q000196:embryology / Q000378:metabolism; D008544:Melanocytes / Q000378:metabolism; D051379:Mice; D008817:Mice, Mutant Strains; D009693:Nucleic Acid Hybridization; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit; D012313:RNA / Q000032:analysis; D013116:Spinal Cord / Q000196:embryology / Q000378:metabolism; D014018:Tissue Distribution; D015017:Yolk Sac / Q000378:metabolism
D016298:Hematopoietic Cell Growth Factors; D011518:Proto-Oncogene Proteins; D012313:RNA; D019009:Proto-Oncogene Proteins c-kit