The Gja5 gene encodes an intercellular channel forming protein, also known as Connexin 40, which functions as a component of gap junctions. These mice carry a knock out mutation of the Gja5 gene in which a PGK-NEO cassette replaces the single coding exon.
No gene product (mRNA or protein) is detected by RT-PCR of heart tissue from homozygous E11.5 embryos, immunohistochemical analysis of heart tissue, immunocytochemical analysis of arterial endothelium, or Western blot analysis of aortic endothelial lysates and whole aorta membranes from homozygotes.
Homozygotes exhibit defects of the cardiovascular system including: cardiac conduction abnormalities, impaired interendothelial communication, impaired propagation of arteriole vasomotor responses, hypertension with elevated renin levels, developmental cardiac malformations, compromised post-ischemic recovery (hindlimb), and reduced platelet function. In addition, malformation of axial and appendicular bones is observed. Homozygotes are fertile, but it should be noted that the Donating Investigator reports that homozygotes have a slightly reduced viability compared to heterozygotes.
During backcrossing, the Y chromosome may not have been fixed to the C57BL/6 genetic background.
