Localization of two Na+- or K+-H+ antiporters, AgNHA1 and AgNHA2, in Anopheles gambiae larval Malpighian tubules and the functional expression of AgNHA2 in yeast

摘要: Abstract The newly identified metazoan Na + /H antiporter (NHA) family is represented by two paralogues, AgNHA1 and AgNHA2, in the genome of African malaria mosquito, Anopheles gambiae . Both antiporters are postulated to be electrophoretic i.e. voltage-driven. was first cloned from An. larvae immunolocalized with respect H V-ATPase Harvey laboratory. Little known about properties NHA1s; attempts characterize exchanger (NHE)-lacking Chinese hamster ovary cells yeast or frog oocytes were unsuccessful. Even less AgNHA2. It predicted have a relative molecular mass ∼60 kDa shares 30.5% amino acid identity AgNHA1. Immunolocalization images show AgNHA2 on apical plasma membrane stellate Malpighian tubules adults. When heterologously expressed mutant strain yeast, Saccharomyces cerevisiae , which lacks endogenous cation/proton pumps, enhanced repression growth alkali metal cations, Li K accumulation. studies invite speculation that an stoichiometry n 1H > 1. provide direct evidence co-localized principal but it not present where localized apically. These results consistent notion outside positive voltage generates across appears little attenuation cells. This immunolocalization pattern hypothesis acts via drive into out lumen lumen. Precious then retained ejection blood basal /K -ATPase. Localizations anion transporters their functions described Linser, Romero associates this volume. role electrogenic cationic anionic play ion homeostasis incorporated model for tubule larval mosquitoes.