title: Immunolocalization of Na+/K(+)-ATPase in mitochondrion-rich cells of the atlantic hagfish (Myxine glutinosa) gill.
abstract: Using a monoclonal antibody for the alpha-subunit of the Na+/K(+)-ATPase, DASPEI (a vital mitochondria dye), and confocal laser scanning microscopy, the presence of Na+/K(+)-ATPase in mitochondrion-rich cells of the hagfish gill was confirmed. In addition, the level of Na+/K(+)-ATPase expression in the hagfish gill was compared to that of fishes with different osmoregulatory strategies (little skate, Raja erinacea and mummichog, Fundulus heteroclitus). Immunocytochemistry detected a high density of columnar cells expressing Na+/K(+)-ATPase in the afferent filamental epithelium. Positive cells were also found in the lamellar epithelium but at a much lower density. The distribution of DASPEI staining was similar to that of the Na+/K(+)-ATPase antibody, indicating that the enzyme is expressed in mitochondrion-rich cells. Immunoblot analysis confirmed the specificity of the antibody for the 97 kDa alpha-subunit of the enzyme. The immunoreactive band intensity for the Atlantic hagfish was similar to that of the little skate, but less than half that of the full-strength seawater mummichog. These results are discussed in relation to gill function in early craniates.
authors.affiliation: Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA. kchoe@zoo.ufl.edu
authors.forename: K P
authors.initials: KP
authors.lastname: Choe
authors.forename: S
authors.initials: S
authors.lastname: Edwards
authors.forename: A I
authors.initials: AI
authors.lastname: Morrison-Shetlar
authors.forename: T
authors.initials: T
authors.lastname: Toop
authors.forename: J B
authors.initials: JB
authors.lastname: Claiborne
mesh_terms: D000818:Animals; D015153:Blotting, Western; D005880:Gills / Q000201:enzymology* / Q000648:ultrastructure; D006196:Hagfishes; D007150:Immunohistochemistry; D008928:Mitochondria / Q000201:enzymology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*
chemical_list: D000254:Sodium-Potassium-Exchanging ATPase