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Published on: November 17, 2010
SLO-1 potassium channels control quantal content of neurotransmitter release at the C. elegans neuromuscular junction
Z W Wang1, O Saifee, M L Nonet
1Department of Anatomy and Neurobiology, Washington University School of Medicine, Campus Box 8108, 660 S. Euclid Avenue, St. Louis, MO 63110, USA.
Abstract:
Six mutants of SLO-1, a large-conductance, Ca(2+)-activated K(+) channel of C. elegans, were obtained in a genetic screen for regulators of neurotransmitter release. Mutants were isolated by their ability to suppress lethargy of an unc-64 syntaxin mutant that restricts neurotransmitter release. We measured evoked postsynaptic currents at the neuromuscular junction in both wild-type and mutants and observed that the removal of SLO-1 greatly increased quantal content primarily by increasing duration of release. The selective isolation of slo-1 as the only ion channel mutant derived from a whole genomic screen to detect regulators of neurotransmitter release suggests that SLO-1 plays an important, if not unique, role in regulating neurotransmitter release.
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