title: Sequence of a probable potassium channel component encoded at Shaker locus of Drosophila.
abstract: Potassium currents are crucial for the repolarization of electrically excitable membranes, a role that makes potassium channels a target for physiological modifications that alter synaptic efficacy. The Shaker locus of Drosophila is thought to encode a K+ channel. The sequence of two complementary DNA clones from the Shaker locus is reported here. The sequence predicts an integral membrane protein of 70,200 daltons containing seven potential membrane-spanning sequences. In addition, the predicted protein is homologous to the vertebrate sodium channel in a region previously proposed to be involved in the voltage-dependent activation of the Na+ channel. These results support the hypothesis that Shaker encodes a structural component of a voltage-dependent K+ channel and suggest a conserved mechanism for voltage activation.
mesh_terms: D000818:Animals; D001483:Base Sequence; D003062:Codon; D004247:DNA / Q000235:genetics*; D004331:Drosophila melanogaster / Q000235:genetics*; D004593:Electrophorus / Q000235:genetics; D005796:Genes; D007473:Ion Channels; D008565:Membrane Proteins / Q000235:genetics*; D009154:Mutation; D011188:Potassium / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism
chemical_list: D003062:Codon; D007473:Ion Channels; D008565:Membrane Proteins; D004247:DNA; D012964:Sodium; D011188:Potassium