Functional Analysis and Tissue‐Specific Expression of Drosophila Na+,K+‐ATPase Subunits

• Published in: Journal of neurochemistry Vol. 71; no. 1; pp. 142 - 151
• Main Authors: Sun, Banghua, Wang, Weiya, Salvaterra, Paul M.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.07.1998; Blackwell
• Subjects: Age Factors; Analytical, structural and metabolic biochemistry; Animals; Antibodies, Monoclonal; Antibody Specificity; Biological and medical sciences; Blotting, Western; Cloning, Molecular; DNA, Complementary; Drosophila; Drosophila - enzymology; Enzyme Inhibitors; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Enzymologic; Hydrolases; Isoenzymes - genetics; Isoenzymes - immunology; Isoenzymes - metabolism; Molecular Sequence Data; Na+,K+‐ATPase; Nervana; Nervous System - enzymology; Nervous system‐specific isoform; Oocytes - physiology; Ouabain; Ribonucleases; RNA, Messenger - analysis; Rubidium Radioisotopes; Sodium-Potassium-Exchanging ATPase - genetics; Sodium-Potassium-Exchanging ATPase - immunology; Sodium-Potassium-Exchanging ATPase - metabolism; Tritium; Xenopus; β subunit; Molecular form; Enzyme; Insecta; Drosophila; Beta-Peptide chain; Central nervous system; Tissue specificity; K; Gene expression; Drosophilidae; Na; Arthropoda; Hydrolases; exchanging ATPase; Invertebrata; Diptera
• ISSN: 0022-3042; 1471-4159
• DOI: 10.1046/j.1471-4159.1998.71010142.x

: We have previously purified and characterized a nervous system‐specific glycoprotein antigen from adult Drosophila heads, designated Nervana [nerve antigen (NRV)] and identified two separate genes coding for three different proteins. All three proteins share homology with the β subunits of Na+,K+‐ATPase from various other species. In this study we have isolated a new Drosophila Na+,K+‐ATPase α subunit cDNA clone (PSα; GenBank accession no. AF044974) and demonstrate expression of functional Na+,K+‐ATPase activity when PSα mRNA is coinjected into Xenopus oocytes along with any of the three different Nrv mRNAs. Western blotting, RNase protection assays, and immunocytochemical staining of adult fly sections indicate that NRV2 is expressed primarily in the nervous system. Staining is most intense in the brain and thoracic ganglia and is most likely associated with neuronal elements. NRV1 is more broadly expressed in muscle and excretory tissue and also shows diffuse distribution in the nervous system. Similar to other species, Drosophila expresses multiple isoforms of Na+,K+‐ATPase subunits in a tissue‐ and cell type‐specific pattern. It will now be possible to use the advantages of Drosophila molecular and classical genetics to investigate the phenotypic consequences of altering Na+,K+‐ATPase expression in various cell and tissue types.