title: Structural requirements for rapid inactivation and voltage dependence in splice variants of lobster Shaker potassium channels.
abstract: We studied the properties of currents generated in Xenopus oocytes by nine splice variants of the spiny lobster Shaker gene. These isoforms differ in their amino termini and in the P-loop region of the pore. Both the voltage dependence and kinetic properties of the currents varied significantly, depending on which amino terminus was present. A cluster of net positive charges at the N-terminus was not necessary for rapid inactivation: negatively charged N-termini also inactivated rapidly. There was no obvious correlation between N-terminus length and inactivation rate. These N-terminal effects were additive with a separate set of voltage and kinetic properties controlled by the two alternative P-loop exons.
authors.affiliation: Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, USA. lfrench@allegheny.edu
authors.forename: L B
authors.initials: LB
authors.lastname: French
authors.forename: A
authors.initials: A
authors.lastname: Singh
authors.forename: R
authors.initials: R
authors.lastname: Luik
authors.forename: R M
authors.initials: RM
authors.lastname: Harris-Warrick
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D004594:Electrophysiology; D005260:Female; D015640:Ion Channel Gating; D007700:Kinetics; D008969:Molecular Sequence Data; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D033521:Palinuridae / Q000502:physiology*; D015221:Potassium Channels / Q000235:genetics / Q000502:physiology*; D020033:Protein Isoforms; D017384:Sequence Deletion; D051637:Shaker Superfamily of Potassium Channels; D014982:Xenopus laevis
chemical_list: D015221:Potassium Channels; D020033:Protein Isoforms; D051637:Shaker Superfamily of Potassium Channels