The skeletal muscle dihydropyridine receptor/Ca2+ channel is composed of five protein components (alpha 1, alpha 2 delta, beta, and gamma). Only two such components, alpha 1 and alpha 2, have been identified in heart. The present study reports the cloning and expression of a novel beta gene that is expressed in heart, lung, and brain. Coexpression of this beta with a cardiac alpha 1 in Xenopus oocytes causes the following changes in Ca2+ channel activity: it increases peak currents, accelerates activation kinetics, and shifts the current-voltage relationship toward more hyperpolarized potentials. It also increases dihydropyridine binding to alpha 1 in COS cells. These results indicate that the cardiac L-type Ca2+ channel has a similar subunit structure as in skeletal muscle, and provides evidence for the modulatory role of the beta subunit.
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| rdf:type | |
| rdfs:comment |
The skeletal muscle dihydropyridine receptor/Ca2+ channel is composed of five protein components (alpha 1, alpha 2 delta, beta, and gamma). Only two such components, alpha 1 and alpha 2, have been identified in heart. The present study reports the cloning and expression of a novel beta gene that is expressed in heart, lung, and brain. Coexpression of this beta with a cardiac alpha 1 in Xenopus oocytes causes the following changes in Ca2+ channel activity: it increases peak currents, accelerates activation kinetics, and shifts the current-voltage relationship toward more hyperpolarized potentials. It also increases dihydropyridine binding to alpha 1 in COS cells. These results indicate that the cardiac L-type Ca2+ channel has a similar subunit structure as in skeletal muscle, and provides evidence for the modulatory role of the beta subunit.
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| skos:exactMatch | |
| uniprot:name |
J. Biol. Chem.
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| uniprot:author |
Baggstrom E.,
Bertrand P.,
Birnbaumer L.,
Castellano A.,
Kim H.S.,
Lacerda A.E.,
Perez-Reyes E.,
Wei X.Y.
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| uniprot:date |
1992
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| uniprot:pages |
1792-1797
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| uniprot:title |
Cloning and expression of a cardiac/brain beta subunit of the L-type calcium channel.
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| uniprot:volume |
267
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