Journal of Neuroscience, Vol 11, 918-927, Copyright © 1991 by Society for 
Neuroscience 


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

PJ Pfaffinger, Y Furukawa, B Zhao, D Dugan and ER Kandel 

Howard Hughes Medical Institute, Department of Physiology and Biophysics, 
Columbia University, College of Physicians and Surgeons, New York, New York 
10032. 

We describe here the cloning of the Aplysia K+ channel AK01a.AK01a 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 ShakerK+ channel 
family. Expression of the AK01a channel in Xenopus oocytes produces a rapidly 
inactivating outward potassium current (IAK01a) 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 (IAdepoI) in a subset of 
Aplysia neurons that has similar gating and pharmacological properties to 
IAK01a.