Splicing of α1A subunit gene generates phenotypic variants of P- and Q-type calcium channels

P-type and Q-type calcium channels mediate neurotransmitter release at many synapses in the mammalian nervous system. The or,, calcium channel has been implicated in the etiologies of conditions such as episodic ataxia, epilepsy and familial migraine, and shares several properties with native P- and Q-type channels. However, the exact relationship between alpha(1A) and P- and Q-type channels is unknown. Here we report that alternative splicing of the alpha(1A) subunit gene results in channels with distinct kinetic, pharmacological and modulatory properties. Overall, the results indicate that alternative splicing of the alpha(1A) gene generates P-type and Q-type channels as well as multiple phenotypic variants.