Bcl-2 protein expression during murine development

Am J Pathol. 1994 Jul;145(1):61-73.


Bcl-2 functions as a death repressor molecule in an evolutionarily conserved cell death pathway. To further explore the role of Bcl-2 in development, we assessed its pattern of expression during murine embryogenesis. Immunohistochemical analysis demonstrates that Bcl-2 is widely expressed early in mouse fetal development in tissues derived from all three germ layers and that this expression becomes restricted with maturation. Within epithelium, the E12.5 lung bud demonstrates a proximal to distal gradient of Bcl-2 expression which is enhanced by E18.5. Bcl-2 is expressed throughout the intestinal epithelium through E14.5, but by E18.5 only cells in the crypts and lower villi express Bcl-2. In the mesoderm-derived kidney, Bcl-2 is expressed in both the ureteric bud and metanephric cap tissue at E12.5. Tubular structures also express Bcl-2, although overall levels drop as the kidney matures. Retinal neuroepithelial cells uniformly express Bcl-2 until cells begin to differentiate and then display the topographic distribution maintained into adulthood. The developing limb provides a clear example where Bcl-2 is restricted to zones of cell survival; Bcl-2 is expressed in the digital zones but not in the interdigital zones of cell death. The wide distribution of Bcl-2 in the developing mouse suggests that many immature cells require a death repressor molecule or that Bcl-2 may have roles beyond regulating developmental cell death.

Publication types

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

MeSH terms

  • Animals
  • Brain Chemistry
  • Embryo, Mammalian / chemistry*
  • Embryonic and Fetal Development*
  • Epithelium / chemistry
  • Extremities / embryology
  • Intestine, Small / chemistry
  • Intestine, Small / embryology
  • Kidney / chemistry
  • Kidney / embryology
  • Liver / chemistry
  • Liver / embryology
  • Lung / chemistry
  • Lung / embryology
  • Mice
  • Mice, Inbred C3H
  • Mice, Inbred C57BL
  • Proto-Oncogene Proteins / analysis*
  • Proto-Oncogene Proteins c-bcl-2
  • Sense Organs / chemistry


  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-bcl-2