A family of γ-like calcium channel subunits

• Published in: FEBS letters 2000-03, Vol.470 (2), p.189-197
• Main Authors: Klugbauer, Norbert, Dai, Shuiping, Specht, Verena, Lacinová, Lubica, Marais, Elsé, Bohn, Georg, Hofmann, Franz
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Barium - metabolism; Blotting, Western; Brain - metabolism; Calcium - metabolism; Calcium channel; Calcium Channels, T-Type - chemistry; Calcium Channels, T-Type - genetics; Calcium Channels, T-Type - metabolism; Cell Line; Cloning, Molecular; Electric Conductivity; Electrophysiology; Expressed Sequence Tags; Gamma subunit; Gene Expression Profiling; Humans; In Situ Hybridization; Kinetics; Mice; Molecular diversity; Molecular Sequence Data; Multigene Family - genetics; Organ Specificity; Protein Isoforms - chemistry; Protein Isoforms - genetics; Protein Isoforms - metabolism; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; RNA, Messenger - analysis; RNA, Messenger - genetics; Sequence Alignment; Transfection; Voltage gated
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/S0014-5793(00)01306-5

The γ subunit was initially identified as an auxiliary subunit of the skeletal muscle calcium channel complex. Evidence for the existence of further γ subunits arose following the characterization of a genetic defect that induces epileptic seizures in stargazer mice. We present here the first account of a family of at least five putative γ subunits that are predominantly expressed in brain. The γ-2 and γ-4 subunits shift the steady-state inactivation curve to more hyperpolarized potentials upon coexpression with the P/Q type α 1A subunit. The coexpression of the γ-5 subunit accelerates the time course of current activation and inactivation of the α 1G T-type calcium channel.