Effects of gap junction inhibitors on the survival and diuretic capacity of adult female mosquitoes, Aedes aegypti

Gap junctions (GJ) mediate direct intercellular communication by forming channels through which certain small molecules and/or ions can pass. GJ are well studied in vertebrates where they contribute to neuronal, muscular and epithelial physiology. In contrast, GJ are not as well studied insects, and their physiological roles remain to be elucidated.  However, it assumed that they play similar roles as in mammals.  Here we assess the effects of three commercially available GJ blockers on the survival and diuretic capacity of the yellow fever mosquito Aedes aegypti. We demonstrate that the gap junction blockers kill mosquitoes in a dose-dependent manner when injected directly into the hemolymph and also exhibit lethal effects when applied topically to the cuticle.  Moreover, we demonstrate that the inhibitors reduce the excretory capacity of the mosquitoes, suggesting roles of GJ in the Malpighian tubules, hindgut, and/or the neuroendocrine system.  In conclusion, our study demonstrates that GJ play essential physiological roles in mosquitoes.  Supported by grants from the Ohio Mosquito Control Association to TLC, and the NIH (R03DK090186) to PMP.