Characterization of Dir: a putative potassium inward rectifying channel in Drosophila.
Potassium channels vary in their function and regulation, yet they maintain a number of important features - they are involved in the control of potassium flow, cell volume, cell membrane resting potential, cell excitability and hormone release. The potassium (K(+)) inward rectifier (Kir) superfamily of channels are potassium selective channels, that are sensitive to the concentration of K(+) ions. They are termed inward rectifiers since they allow a much greater K(+) influx than efflux. There are at least seven subfamilies of Kir channels, grouped according to sequence and functional similarities (Curr. Opin. Neurobiol. 5 (1995) 268; Annu. Rev. Physiol. 59 (1997) 171). While numerous Kir channels have been discovered in a variety of organisms, Drosophila inward rectifier (Dir) is the first putative inward rectifier to be studied in Drosophila. In fact, there are only three genes (including Dir) encoding putative inward rectifiers in the Drosophila genome. Though there are other known potassium channels in Drosophila such as ether-a-go-go and shaker, most are voltage-gated channels. As an important first step in characterizing Kir channels in Drosophila, we initiated studies on Dir.
Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia Canada V5A 1S6.
Sheila J
SJ
MacLean
Bryan C
BC
Andrews
Esther M
EM
Verheyen
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D010802:Phylogeny; D024661:Potassium Channels, Inwardly Rectifying / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D029721:Drosophila Proteins; C471706:Irk1 protein, Drosophila; D024661:Potassium Channels, Inwardly Rectifying