Expression of N-CAM in fertilized pre- and periimplantation and parthenogenetically activated mouse embryos.
The expression of the cell adhesion molecule of the immunoglobulin family, neural cell adhesion molecule (N-CAM), in the pre- and periimplantation embryo was examined by immunocytochemistry. N-CAM is expressed on unfertilized ovulated oocytes, fertilized preimplantation embryos at all stages of development and parthenogenetically activated eggs and embryos. In fertilized embryos, expression from the 4-cell stage can be partially inhibited by blocking embryonic transcription before 38 h post human chorionic gonadotropin (hCG). Expression of N-CAM was reduced on the trophoblast of day 6 blastocysts in culture, weak on the trophoblast of embryonic outgrowths and disappears from invading trophoblast in utero. An antibody against alpha(2-8) linked polysialic acid, mAb2-2B, reacted with embryos from the 8-cell stage, and staining was similarly reduced on the trophoblast of blastocysts at the time of implantation. These results suggest a role for N-CAM in the interactions of cells of the preimplantation mammalian embryo which requires further investigation.
Kimber
S J
SJ
School of Biological Sciences, University of Manchester, United Kingdom.
Bentley
J
J
Ciemerych
M
M
Moller
C J
CJ
Bock
E
E
D000546:Amanitins / Q000494:pharmacology; D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000032:analysis* / Q000235:genetics / Q000502:physiology*; D002478:Cells, Cultured; D004622:Embryo, Mammalian / Q000737:chemistry* / Q000166:cytology / Q000502:physiology*; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D007150:Immunohistochemistry; D051379:Mice; D009865:Oocytes / Q000737:chemistry / Q000166:cytology / Q000502:physiology; D010312:Parthenogenesis; D011247:Pregnancy; D014158:Transcription, Genetic
D000546:Amanitins; D015816:Cell Adhesion Molecules, Neuronal