Cloning, chromosomal localization, and functional expression of the alpha 1 subunit of the L-type voltage-dependent calcium channel from normal human heart.
A unique structural variant of the cardiac L-type voltage-dependent calcium channel alpha 1 subunit cDNA was isolated from libraries derived from normal human heart mRNA. The deduced amino acid sequence shows significant homology to other calcium channel alpha 1 subunits. However, differences from the rabbit heart alpha 1 include a shortened N-terminus, a unique C-terminal insertion, and both forms of an alternatively spliced motif IV S3 region. The shortened N-terminus provides optimal access to consensus sequences thought to facilitate translation. Northern blot analysis revealed a single hybridizing mRNA species of 9.4 kb. The gene for the human heart alpha 1 subunit was localized specifically to the distal region of chromosome 12p13. The cloned alpha 1 subunit was expressed in Xenopus oocytes and single-channel analyses revealed native-like pharmacology and channel properties.
Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, OH 45267-0575.
D
D
Schultz
G
G
Mikala
A
A
Yatani
D B
DB
Engle
D E
DE
Iles
B
B
Segers
R J
RJ
Sinke
D O
DO
Weghuis
U
U
Klöckner
M
M
Wakamori
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015220:Calcium Channels; D002874:Chromosome Mapping; D002881:Chromosomes, Human, Pair 12; D003001:Cloning, Molecular; D006224:Cricetinae; D004247:DNA / Q000737:chemistry / Q000302:isolation & purification; D006801:Humans; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009206:Myocardium / Q000378:metabolism*; D011817:Rabbits; D051381:Rats
D015220:Calcium Channels; D004247:DNA