Disproportionate alpha- and beta-mRNA sodium pump subunit content in canine vascular smooth muscle.
Total RNA isolated from canine saphenous vein smooth muscle cells was examined for Na+ pump alpha- and beta-mRNA content by three increasingly sensitive methods: Northern analysis, RNase protection assay, and polymerase chain reaction. Northern analysis clearly showed the presence of beta-mRNA. An alpha 1 signal was not demonstrable using either Northern analysis with a 1.5-kb cDNA probe or RNase protection. However, an "alpha 1-like" transcript was detected using polymerase chain reaction with two sets of primers constructed to selected areas of the rat alpha 1-cDNA. These data suggest that beta-mRNA in canine blood vessels is in large excess of the alpha 1-mRNA. This discrepancy may be reflected in the relatively low number of Na+ pump sites in this tissue.
Allen
J C
JC
Department of Medicine, Baylor College of Medicine, Houston, TX 77030-3498.
Medford
R M
RM
Zhao
X
X
Pressley
T A
TA
D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D004285:Dogs; D008969:Molecular Sequence Data; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism*; D015222:Sodium Channels / Q000235:genetics*
D012333:RNA, Messenger; D015222:Sodium Channels