Meeting Abstract
The genome of Aedes aegypti contains three genes with sequence similarity to the sodium-dependent cation-chloride cotransporters (CCCs). AeNKCC1 groups in a clade with Drosophila ncc69, which is a canonical Na-K-Cl cotransporter and participates in potassium secretion by Malpighian tubules. AeCCC2 and aeCCC3 group with Drosophila ncc83 in an insect-specific CCC clade. Previous work showed that transcripts of aeCCC3 are highly expressed in the anal papillae of larvae. AeCCC2 is most highly expressed in hindgut of adult mosquitos, but also found in Malpighian tubules of larvae and adults. We hypothesize that aeCCC2 contributes to salt transport across Aedes aegypti epithelia. To assess cellular localization of aeCCC2, we developed polyclonal antibodies against isoform-specific peptides from the C-terminal cytoplasmic region of aeCCC2 and aeCCC3. The specificity of the antibodies was confirmed by reactivity to oocytes expressing either aeCCC2 or aeCCC3. We performed immunohistochemistry on whole-mounted larval and adult Aedes aegypti gut tissue, and visualized Alexa 488-coupled secondary antibody by confocal microscopy. In both larvae and adults, the aeCCC2 antibody stained Malpighian tubules and hindgut. Staining of the larval Malpighian tubule was primarily on the basolateral membrane of principal cells. In adult females, aeCCC2 stained midgut and hindgut, with detectable but lower staining on the Malpighian tubules. The ovaries of adult females were also stained. These data support the hypothesis that aeCCC2 contributes to transepithelial salt transport, but further work is needed to understand its specific roles. Funding: NSF-IOS-1557230, Kenyon College, and State and Federal funds appropriated to the Ohio Agricultural Research and Development Center of The Ohio State University.
