title: Expression of a duplicate Na,K-ATPase beta(1)-isoform in the European eel (Anguilla anguilla).
abstract: Recent studies on teleost fish have suggested that their genomes have undergone ancient polyploidization events resulting in the duplication of the genome. A duplicate copy of the Na,K-ATPase beta(1)-isoform (called beta(233)) has been identified in the European eel (Anguilla anguilla). The beta(233)-isoform shares high levels of nucleotide (74.8%) and amino acid (69.9%) homology with the eel beta(1)-subunit as well as other vertebrate beta(1)-sequences. Compared with the widely expressed beta(1)-isoform, expression of beta(233)-mRNA is mainly restricted to epithelial tissues. Seawater acclimation induced increases in beta(233)-mRNA levels in kidney, gill, and intestine of migratory "silver" but not the nonmigratory "yellow" adult eels, suggesting that the factors responsible for this upregulation are themselves developmentally regulated. Expression of a variably glycosylated 40- to 52-kDa beta(233)-protein in both gill "chloride" and intestinal epithelial cells suggests that the beta(233)-isoform of Na,K-ATPase may play an important functional role in the major osmoregulatory tissues of euryhaline fish such as the eel.
authors.affiliation: School of Biology, Bute Medical Buildings, University of Saint Andrews, Saint Andrews, Fife, Scotland KY16 9TS. -cpc@st-and.ac.uk
authors.forename: C P
authors.initials: CP
authors.lastname: Cutler
authors.forename: S
authors.initials: S
authors.lastname: Brezillon
authors.forename: S
authors.initials: S
authors.lastname: Bekir
authors.forename: I L
authors.initials: IL
authors.lastname: Sanders
authors.forename: N
authors.initials: N
authors.lastname: Hazon
authors.forename: G
authors.initials: G
authors.lastname: Cramb
mesh_terms: D020121:5' Untranslated Regions / Q000235:genetics; D000064:Acclimatization / Q000502:physiology; D000811:Anguilla / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D001921:Brain / Q000378:metabolism; D004947:Esophagus / Q000378:metabolism; D005123:Eye / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D005880:Gills / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007527:Isoenzymes / Q000096:biosynthesis; D007668:Kidney / Q000378:metabolism; D008969:Molecular Sequence Data; D009928:Organ Specificity; D012333:RNA, Messenger / Q000096:biosynthesis; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D000254:Sodium-Potassium-Exchanging ATPase / Q000096:biosynthesis* / Q000235:genetics*; D013154:Spleen / Q000378:metabolism
chemical_list: D020121:5' Untranslated Regions; D007527:Isoenzymes; D012333:RNA, Messenger; D000254:Sodium-Potassium-Exchanging ATPase