Coexpression of skeletal muscle voltage-dependent calcium channel alpha 1 and beta cDNAs in mouse Ltk- cells increases the amount of alpha 1 protein in the cell membrane.
Coexpression of alpha 1 and beta subunits for all tissue-specific isotypes of calcium channels results in an increase in Ca2+ channel current density and drug receptor function. The quantification of the photoaffinity labeled skeletal muscle alpha 1 subunit polypeptide by two alternative immunoadsorption techniques showed that 3 times higher amount of calcium channel alpha 1 protein appears in the cell membrane when alpha 1 and beta subunits were coexpressed compared to alpha 1 alone. Using Western blotting and immunodetection techniques, we identified two polypeptide bands of alpha 1 with 210 kDa and 170 kD molecular mass, respectively. The combined intensity of these bands was 7-9 times higher when alpha 1 and beta were coexpressed compared to alpha 1 alone. The data provide evidence that coexpression of alpha 1 and beta results in an increased amount of alpha 1 protein in the cell membrane.
Krizanova
O
O
Institute of Molecular Pharmacology and Biophysics, University of Cincinnati, OH 45267-0828, USA.
Varadi
M
M
Schwartz
A
A
Varadi
G
G
D000494:Allosteric Regulation; D000818:Animals; D015220:Calcium Channels / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D020746:Calcium Channels, L-Type; D002462:Cell Membrane / Q000502:physiology*; D002478:Cells, Cultured; D004553:Electric Conductivity; D015151:Immunoblotting; D015640:Ion Channel Gating; D007739:L Cells; D046911:Macromolecular Substances; D008564:Membrane Potentials; D051379:Mice; D009124:Muscle Proteins / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D011487:Protein Conformation; D011994:Recombinant Proteins
D015220:Calcium Channels; D020746:Calcium Channels, L-Type; D046911:Macromolecular Substances; D009124:Muscle Proteins; D011994:Recombinant Proteins