Formation of intermediate-conductance calcium-activated potassium channels by interaction of Slack and Slo subunits.

TitleFormation of intermediate-conductance calcium-activated potassium channels by interaction of Slack and Slo subunits.
Publication TypeJournal Article
Year of Publication1998
AuthorsJoiner WJ, Tang MD, Wang LY, Dworetzky SI, Boissard CG, Gan L, Gribkoff VK, Kaczmarek LK
JournalNat Neurosci
Volume1
Issue6
Pagination462-9
Date Published1998 Oct
ISSN1097-6256
KeywordsAmino Acid Sequence, Animals, Caenorhabditis elegans, Caenorhabditis elegans Proteins, Electric Conductivity, Intermediate-Conductance Calcium-Activated Potassium Channels, Isomerism, Large-Conductance Calcium-Activated Potassium Channels, Molecular Sequence Data, Nerve Tissue Proteins, Potassium Channels, Potassium Channels, Calcium-Activated
Abstract

Large-conductance calcium-activated potassium channels (maxi-K channels) have an essential role in the control of excitability and secretion. Only one gene Slo is known to encode maxi-K channels, which are sensitive to both membrane potential and intracellular calcium. We have isolated a potassium channel gene called Slack that is abundantly expressed in the nervous system. Slack channels rectify outwardly with a unitary conductance of about 25-65 pS and are inhibited by intracellular calcium. However, when Slack is co-expressed with Slo, channels with pharmacological properties and single-channel conductances that do not match either Slack or Slo are formed. The Slack/Slo channels have intermediate conductances of about 60-180 pS and are activated by cytoplasmic calcium. Our findings indicate that some intermediate-conductance channels in the nervous system may result from an interaction between Slack and Slo channel subunits.

DOI10.1038/2176
Alternate JournalNat. Neurosci.
PubMed ID10196543