CAPA Neuropeptides Inhibit VA Activity in Malpighian Tubules of the Mosquito, Aedes Aegypti

• Published in: Journal of the Endocrine Society 2021-05, Vol.5 (Supplement_1), p.A498-A499
• Main Authors: Sajadi, Farwa, Paluzzi, Jean-Paul
• Format: Article
• Language: English
• ISSN: 2472-1972; 2472-1972
• DOI: 10.1210/jendso/bvab048.1019

Haematophagus insects, such as the female Aedes aegypti mosquito, face the challenge of excess ion and water intake after engorgement on a blood meal. To cope with this, adult female A. aegypti have a specialized excretory system that includes the Malpighian tubules (MTs), which are under rigorous control by several neuroendocrine factors to regulate transepithelial movement of ions/water. Produced in the CNS, the mosquito anti-diuretic hormone is a member of the CAPA peptide family, which share homology to the vertebrate neuromedin U peptide. CAPA peptides inhibit fluid secretion of MTs stimulated by select diuretic factors, 5HT and DH31 through the NOS/cGMP/PKG pathway. However, the anti-diuretic signalling mechanism and downstream cellular targets, such as ion channels and transporters, remain unclear. To study whether the V-type H+-ATPase (VA) plays a role in CAPA inhibition, we performed fluid secretion assays in MTs treated with diuretics and bafilomycin, a known VA inhibitor. Bafilomycin significantly inhibited DH31-stimulated fluid secretion 30 min post treatment compared to diuretic controls (p