The cloned human cardiac L-type calcium channel alpha 1 subunit, localized to chromosome 12p13, exhibited native-like pharmacology and channel properties when expressed in Xenopus oocytes.
The cloning and functional expression of the human cardiac L-type calcium channel alpha 1 subunit provides a foundational model for studying human cardiac electrophysiology and pharmacology.
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.
Schultz et al. (Thu,) reported a other. Cloning and expression of cardiac L-type voltage-dependent calcium channel alpha 1 subunit was evaluated on Structural characteristics, chromosomal localization, and functional expression. The cloned human cardiac L-type calcium channel alpha 1 subunit, localized to chromosome 12p13, exhibited native-like pharmacology and channel properties when expressed in Xenopus oocytes.