Deletion of the Na/K-ATPase alpha1-subunit gene (Atp1a1) does not prevent cavitation of the preimplantation mouse embryo

Mech Dev. 2004 May;121(5):417-26. doi: 10.1016/j.mod.2004.04.005.

Abstract

Increases in Na/K-ATPase activity occur concurrently with the onset of cavitation and are associated with increases in Na(+)-pump subunit mRNA and protein expression. We have hypothesized that the alpha1-isozyme of the Na/K-ATPase is required to mediate blastocyst formation. We have tested this hypothesis by characterizing preimplantation development in mice with a targeted disruption of the Na/K-ATPase alpha1-subunit (Atp1a1) using embryos acquired from matings between Atp1a1 heterozygous mice. Mouse embryos homozygous for a null mutation in the Na/K-ATPase alpha1-subunit gene are able to undergo compaction and cavitation. These findings demonstrate that trophectoderm transport mechanisms are maintained in the absence of the predominant isozyme of the Na(+)-pump that has previously been localized to the basolateral membranes of mammalian trophectoderm cells. The presence of multiple isoforms of Na/K-ATPase alpha- and beta-subunits at the time of cavitation suggests that there may be a degree of genetic redundancy amongst isoforms of the catalytic alpha-subunit that allows blastocyst formation to progress in the absence of the alpha1-subunit.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blastocyst / cytology*
  • Blastocyst / immunology
  • Blastocyst / metabolism*
  • Cell Shape
  • Cell Size
  • Cells, Cultured
  • Female
  • Gene Deletion*
  • Genotype
  • Homozygote
  • Immunohistochemistry
  • Male
  • Mice
  • Mice, Knockout
  • Protein Subunits / deficiency*
  • Protein Subunits / genetics
  • Protein Subunits / immunology
  • Protein Subunits / metabolism
  • Sodium-Potassium-Exchanging ATPase / deficiency*
  • Sodium-Potassium-Exchanging ATPase / genetics
  • Sodium-Potassium-Exchanging ATPase / immunology
  • Sodium-Potassium-Exchanging ATPase / metabolism
  • Time Factors

Substances

  • Protein Subunits
  • Sodium-Potassium-Exchanging ATPase