title: Structural analysis of the α subunit of Na(+)/K(+) ATPase genes in invertebrates.
abstract: The Na(+)/K(+) ATPase is a ubiquitous pump coordinating the transport of Na(+) and K(+) across the membrane of cells and its role is fundamental to cellular functions. It is heteromer in eukaryotes including two or three subunits (α, β and γ which is specific to the vertebrates). The catalytic functions of the enzyme have been attributed to the α subunit. Several complete α protein sequences are available, but only few gene structures were characterized. We identified the genomic sequences coding the α-subunit of the Na(+)/K(+) ATPase, from the whole-genome shotgun contigs (WGS), NCBI Genomes (chromosome), Genomic Survey Sequences (GSS) and High Throughput Genomic Sequences (HTGS) databases across distinct phyla. One copy of the α subunit gene was found in Annelida, Arthropoda, Cnidaria, Echinodermata, Hemichordata, Mollusca, Placozoa, Porifera, Platyhelminthes, Urochordata, but the nematodes seem to possess 2 to 4 copies. The number of introns varied from 0 (Platyhelminthes) to 26 (Porifera); and their localization and length are also highly variable. Molecular phylogenies (Maximum Likelihood and Maximum Parsimony methods) showed some clusters constituted by (Chordata/(Echinodermata/Hemichordata)) or (Plathelminthes/(Annelida/Mollusca)) and a basal position for Porifera. These structural analyses increase our knowledge about the evolutionary events of the α subunit genes in the invertebrates.
authors.affiliation: University of Sfax, Laboratory of Biodiversity and Aquatic Ecosystems UR/11ES72, Ecology and Planktonology, Department of Life Sciences, Road Soukra Km 3.5, BP1171, 3000, Sfax, Tunisia.
authors.forename: Rahma
authors.initials: R
authors.lastname: Thabet
authors.affiliation: Laboratoire Evolution, Genomes et Speciation, UPR9034, CNRS, 91198 Gif-sur-Yvette, France.
authors.forename: J-D
authors.initials: JD
authors.lastname: Rouault
authors.affiliation: University of Sfax, Laboratory of Biodiversity and Aquatic Ecosystems UR/11ES72, Ecology and Planktonology, Department of Life Sciences, Road Soukra Km 3.5, BP1171, 3000, Sfax, Tunisia.
authors.forename: Habib
authors.initials: H
authors.lastname: Ayadi
authors.affiliation: Université du Maine, Laboratoire Mer Molecule Sante EA 2160 FR-CNRS 3473 IUML, 72085 Le Mans, France. Electronic address: Vincent.leignel@univ-lemans.fr.
authors.forename: Vincent
authors.initials: V
authors.lastname: Leignel
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D055162:Biocatalysis; D030541:Databases, Genetic; D019143:Evolution, Molecular; D023281:Genomics; D007448:Invertebrates / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D021122:Protein Subunits / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D021122:Protein Subunits; D000254:Sodium-Potassium-Exchanging ATPase
keywords: Alpha subunit; Animal kingdom; Evolution; Genome; Sodium–potassium ATPase