Ouabain-sensitive (Na+ + K+)-ATPase activity expressed in mouse L cells by transfection with DNA encoding the alpha-subunit of an avian sodium pump.
cDNA encoding the alpha-subunit of the (Na+ + K+)-ATPase was cloned from a chicken kidney cDNA library and the nucleotide sequence determined. The deduced amino acid sequence showed 92% sequence homology with the alpha-subunit of the sheep kidney (Na+ + K+)-ATPase, and high cross-species homologies were found among nucleotide sequences both in the 5'- and 3'-untranslated regions of the "kidney-type" alpha-subunit mRNAs. The cDNA was subcloned into a shuttle vector derived from pSV2CAT and was stably incorporated into mouse Ltk- cells. Expression of the avian alpha-sub-unit could be activated by culture of the cells in 10 mM butyrate. Cells expressing avian alpha-subunits displayed high-affinity ouabain binding (KD = 2.6 +/- 0.7 x 10(-7) M) and ouabain-sensitive 86Rb+ uptake, characteristic of avian cells.
Takeyasu
K
K
Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218.
Tamkun
M M
MM
Renaud
K J
KJ
Fambrough
D M
DM
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D002642:Chick Embryo; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis*; D005347:Fibroblasts / Q000201:enzymology; D046911:Macromolecular Substances; D051379:Mice; D008969:Molecular Sequence Data; D010042:Ouabain / Q000494:pharmacology*; D012413:Rubidium / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
D046911:Macromolecular Substances; D010042:Ouabain; D004247:DNA; D000254:Sodium-Potassium-Exchanging ATPase; D012413:Rubidium