Two inwardly rectifying potassium channels,Irk1andIrk2, play redundant roles inDrosophilarenal tubule function

• DOI: 10.1152/ajpregu.00148.2015
• Publication Date: 2015-07-30T03:15:04Z
• Authors: Yipin Wu; Michel Baum; Chou-Long Huang; Aylin R. Rodan
• Keywords: Tubule

Inwardly rectifying potassium channels play essential roles in renal physiology across phyla. Barium-sensitive K(+) conductances are found on the basolateral membrane of a variety insect Malpighian (renal) tubules, including Drosophila melanogaster. We that barium decreases lumen-positive transepithelial potential difference isolated perfused tubules and fluid secretion flux. In those species which it has been studied, transcripts from multiple genes encoding inwardly expressed (Malpighian) tubule. melanogaster, this includes Irk1, Irk2, Irk3 genes. The role each these gene products tubule function is unknown. simultaneous knockdown Irk1 Irk2 principal cell fly flux, with no additive effect knockdown, sensitivity flux by ∼50%. Knockdown any three individually effect, nor does knocking down simultaneously or Irk2. Irk1/Irk2 double-knockdown remain sensitive to kaliuretic cAMP. Inhibition Na(+)/K(+)-ATPase ouabain double have effects 75% transport due ouabain-sensitive pathways. conclusion, redundant ion melanogaster Na(+)/K(+)-ATPase-dependent