title: Characterization of Carbonic Anhydrase 9 in the Alimentary Canal of Aedes aegypti and Its Relationship to Homologous Mosquito Carbonic Anhydrases.
abstract: In the mosquito midgut, luminal pH regulation and cellular ion transport processes are important for the digestion of food and maintenance of cellular homeostasis. pH regulation in the mosquito gut is affected by the vectorial movement of the principal ions including bicarbonate/carbonate and protons. As in all metazoans, mosquitoes employ the product of aerobic metabolism carbon dioxide in its bicarbonate/carbonate form as one of the major buffers of cellular and extracellular pH. The conversion of metabolic carbon dioxide to bicarbonate/carbonate is accomplished by a family of enzymes encoded by the carbonic anhydrase gene family. This study characterizesAedes aegypticarbonic anhydrases using bioinformatic, molecular, and immunohistochemical methods. Our analyses show that there are fourteenAedes aegypticarbonic anhydrase genes, two of which are expressed as splice variants. The carbonic anhydrases were classified as either integral membrane, peripheral membrane, mitochondrial, secreted, or soluble cytoplasmic proteins. Using polymerase chain reaction and Western blotting, one of the carbonic anhydrases,Aedes aegypticarbonic anhydrase 9, was analyzed and found in each life stage, male/female pupae, male/female adults, and in the female posterior midgut. Next, carbonic anhydrase 9 was analyzed in larvae and adults using confocal microscopy and was detected in the midgut regions. According to our analyses, carbonic anhydrase 9 is a soluble cytoplasmic enzyme found in the alimentary canal of larvae and adults and is expressed throughout the life cycle of the mosquito. Based on previous physiological analyses of adults and larvae, it appears AeCA9 is one of the major carbonic anhydrases involved in producing bicarbonate/carbonate which is involved in pH regulation and ion transport processes in the alimentary canal. Detailed understanding of the molecular bases of ion homeostasis in mosquitoes will provide targets for novel mosquito control strategies into the new millennium.
authors.affiliation: The Whitney Laboratory, University of Florida, Saint Augustine, FL 32080, USA. ddixonamcd@gmail.com.|The Anastasia Mosquito Control District, St. Augustine Florida, Saint Augustine, FL 32092, USA. ddixonamcd@gmail.com.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Dixon
authors.affiliation: The Whitney Laboratory, University of Florida, Saint Augustine, FL 32080, USA. leslie@whitney.ufl.edu.
authors.forename: Leslie
authors.initials: L
authors.lastname: Van Ekeris
authors.affiliation: The Whitney Laboratory, University of Florida, Saint Augustine, FL 32080, USA. pjl@whitney.ufl.edu.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Linser
mesh_terms: D000330:Aedes / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D000071231:Carbonic Anhydrase IX / Q000378:metabolism*; D002256:Carbonic Anhydrases / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007814:Larva
chemical_list: D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases
keywords: alkaline; carbonic anhydrase (CA); data mining; immunohistochemistry; midgut; molecular phylogenetics; mosquito; pH