Calcium channels from Cyprinus carpio skeletal muscle.
The complete amino acid sequence of the L-type calcium channel alpha 1 subunit from the carp (Cyprinus carpio) white skeletal muscle was deduced by cDNA cloning and sequence analysis. The open reading frame encodes 1852 amino acids (Mr 210,060). A 155-amino acid COOH-terminal sequence (after the fourth internal repeat) is evolutionarily preserved (90% homology) and may represent an important functional domain of L-type calcium channels. The photolabeled, membrane-bound, and purified carp alpha 1 subunits have masses of 211 and 190 kDa. The purified channel could not be phosphorylated by cAMP-dependent protein kinase. Two glycoproteins (alpha 2 subunits) are associated with the alpha 1 subunit and change their apparent masses from 235 and 220 kDa to 159 kDa upon reduction of disulfide bonds. Nucleic acid hybridization with alpha 2 cDNA revealed an 8.0-kilobase transcript in carp skeletal muscle. Evidence for a copurification of subunits similar in size to mammalian beta or gamma subunits was not obtained.
Grabner
M
M
Institut für Biochemische Pharmakologie, Universität Innsbruck, Austria.
Friedrich
K
K
Knaus
H G
HG
Striessnig
J
J
Scheffauer
F
F
Staudinger
R
R
Koch
W J
WJ
Schwartz
A
A
Glossmann
H
H
D000345:Affinity Labels / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001386:Azides / Q000378:metabolism; D005075:Biological Evolution; D015220:Calcium Channels / Q000235:genetics* / Q000378:metabolism; D002347:Carps / Q000235:genetics*; D004095:Dihydropyridines / Q000378:metabolism; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D009132:Muscles / Q000378:metabolism*; D011817:Rabbits; D012689:Sequence Homology, Nucleic Acid
D000345:Affinity Labels; D001386:Azides; D015220:Calcium Channels; D004095:Dihydropyridines; D046911:Macromolecular Substances; C041130:azidopine