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A mutation in the C. elegans EXP-2 potassium channel that alters feeding behavior.

ABSTRACT: The nematode pharynx has a potassium channel with unusual properties, which allows the muscles to repolarize quickly and with the proper delay. Here, the Caenorhabditis elegans exp-2 gene is shown to encode this channel. EXP-2 is a Kv-type (voltage-activated) potassium channel that has inward-rectifying properties resembling those of the structurally dissimilar human ether-à-go-go-related gene (HERG) channel. Null and gain-of-function mutations affect pharyngeal muscle excitability in ways that are consistent with the electrophysiological behavior of the channel, and thereby demonstrate a direct link between the kinetics of this unusual channel and behavior.

SUBMITTER: Davis MW

PROVIDER: S-EPMC3791429 | biostudies-literature | 1999 Dec

REPOSITORIES: biostudies-literature

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A mutation in the C. elegans EXP-2 potassium channel that alters feeding behavior.

Davis M W MW Fleischhauer R R Dent J A JA Joho R H RH Avery L L

Science (New York, N.Y.) 19991201 5449

The nematode pharynx has a potassium channel with unusual properties, which allows the muscles to repolarize quickly and with the proper delay. Here, the Caenorhabditis elegans exp-2 gene is shown to encode this channel. EXP-2 is a Kv-type (voltage-activated) potassium channel that has inward-rectifying properties resembling those of the structurally dissimilar human ether-à-go-go-related gene (HERG) channel. Null and gain-of-function mutations affect pharyngeal muscle excitability in ways that ...[more]

PMID: 10617464

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