Pig kidney Na+,K+-ATPase. Primary structure and spatial organization
cDNAs complementary to pig kidney mRNAs coding for α- and β-subunits of Na+,K+-ATPase were cloned and sequenced. Selective tryptic hydrolysis of the α-subunit within the membrane-bound enzyme and tryptic hydrolysis of the immobilized isolated β-subunit were also performed. The mature α- and β-subunits contain 1016 and 302 amino acid residues, respectively. Structural data on the peptides from extramembrane regions of the α-subunit and on glycopeptides of the β-subunit underlie a model for the transmembrane arrangement of Na+,K+-ATPase polypeptide chains. (Na++ K+)-ATPase α-Subunit β-Subunit cDNA nucleotide sequence Primary structure Glycopeptide Transmembrane arrangement. © 1986.