Previous results showed that mRNA encoding a putative aquaporin (AQP) (GenBankaccession number AF218314) is present in the tracheolar cells associated with female Aedes aegyptiMalpighian tubules. In this study, immuno-histochemistry detected the protein,AeaAQP, also in tra-cheolar cells, suggesting its involvement in water movement in the respiratory system. When expressed in Xenopus oocytes,AeaAQP increased the osmotic water permeability from15·10 )6 to 150 ·10 )6 mÆs )1 , whichwas inhibited by mercury ions. No permeability to glycerol or other solute was observed
