Expression of c-kit encoded at the W locus of mice in developing embryonic germ cells and presumptive melanoblasts

Dev Biol. 1991 Aug;146(2):312-24. doi: 10.1016/0012-1606(91)90233-s.


The W locus of mice encodes the c-kit tyrosine kinase receptor. In embryos homozygous for severe W mutations, the number of germ cells does not increase after 8 days of development, melanocytes do not appear, and production of erythrocytes and mast cells is deficient. To gain some insight into the role of the c-kit receptor, we have used in situ hybridization to explore the time period of expression of c-kit transcripts in early germ cells and melanoblasts. At 6 1/2 days of development, expression was not seen in the embryonic cylinder, but did appear in parietal endoderm. Germ cells displayed a low level of c-kit transcripts from their first appearance in the 7 1/2 -day embryo, continuing through early proliferation and migration to the gonad. During migration, surrounding tissues also expressed c-kit. Expression increased in gonia and then ceased as they became nonproliferative. Expression in presumptive melanoblasts was first seen in the cervical region of 10-day embryos and continued as they spread over the surface of the body, entered the epidermis, and differentiated in hair follicles after birth. The effects of mutations of c-kit on germ cells and melanoblasts can be interpreted as an absence of a proliferative signal shortly after their segregation from other cell types. This signal may be required throughout the proliferative phase of early germ cells [and also in postnatal stages of germ cell development (Manova et al. (1990). Development 110, 1057-1069]. In melanoblasts, c-kit may play a role during both proliferation and differentiation.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Embryonic and Fetal Development*
  • Female
  • Gene Expression
  • Germ Cells / metabolism*
  • Germ Cells / physiology
  • Male
  • Melanocytes / physiology
  • Mice
  • Mice, Inbred ICR
  • Neural Crest / cytology*
  • Neural Crest / physiology
  • Nucleic Acid Hybridization
  • Protein-Tyrosine Kinases / biosynthesis
  • Protein-Tyrosine Kinases / genetics*
  • Proto-Oncogene Proteins / biosynthesis
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins c-kit
  • RNA, Messenger / metabolism


  • Proto-Oncogene Proteins
  • RNA, Messenger
  • Protein-Tyrosine Kinases
  • Proto-Oncogene Proteins c-kit