Malpighian tubules play vital roles in the excretory functions of mosquitoes.  The tubules generate urine by active transepithelial secretion of potassium, sodium, chloride, and water from the hemolymph to the tubule lumen.  Previous physiological studies by our laboratory on isolated mosquito Malpighian tubules have demonstrated that barium-sensitive potassium channels are critical to urine production, but the molecular identities of these channels have not been resolved.  In the present study, we show that: 1) mosquito Malpighian tubules express at least 3 putative inward-rectifying potassium (Kir) channel genes; 2) one of these genes indeed encodes a barium-sensitive potassium channel when expressed heterologously in Xenopus oocytes; and 3) a novel small molecule antagonist of a mosquito Kir channel inhibits urine production in isolated Malpighian tubules and elicits desirable sub-lethal effects in intact mosquitoes when injected into the hemolymph.  Funded by a grant from the Foundation for the NIH, VCTR program.

Renal potassium channels of mosquitoes as potential new insecticidal targets

244th National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.