Differences in Gating among Amino-terminal Variants of Shaker Potassium Channels

Voltage-dependent potassium channels are key molecular elements in the control of membrane excitability and signaling in the nervous system. They play critical roles in the pacemaker activity of endogenously active neurons and are important in the modulation of synaptic function. Potassium channels have been shown to play a central role in the control and modulation of neurotransmitter release. Alterations in potassium channels in presynaptic terminals of Shaker Drosophila mutants lead to delayed action potential repolarization and hyperexcitability at the neuromuscular junction. These effects underlie the behavioral defects in the mutant flies.