Cloning and expression of an Aplysia K+ channel and comparison with native Aplysia K+ currents

Abstract

We describe here the cloning of the Aplysia K+ channel AK01 a. AK01 a codes for a protein of 515 amino acids, shows considerable homology to other cloned potassium channels, and can be classified as a member of the Shaker K+ channel family. Expression of the AK01 a channel in Xenopus oocytes produces a rapidly inactivating outward potassium current (l AK01a) resembling the A-type currents of Drosophila Shaker. Gating for this current is shifted to potentials considerably more positive than the traditional A-currents of Aplysia; we have, however, identified a novel transient potassium current (lAdepol) in a subset of Aplysia neurons that has similar gating and pharmacological properties to lAK01.