Open AccessProtein Carbonylation of an Amino Acid Residue of the Na/K‐ATPase α1 Subunit Determines Na/K‐ATPase Signaling and Sodium Transport in Renal Proximal Tubular Cells
Author(s) -
Yan Yanling,
Shapiro Anna P.,
Mopidevi Brahma R.,
Chaudhry Muhammad A.,
Maxwell Kyle,
Haller Steven T.,
Drummond Christopher A.,
Kennedy David J.,
Tian Jiang,
Malhotra Deepak,
Xie Zijian,
Shapiro Joseph I.,
Liu Jiang
Publication year - 2016
Publication title -
journal of the american heart association
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.494
H-Index - 85
ISSN - 2047-9980
DOI - 10.1161/jaha.116.003675
Subject(s) - ouabain , renal sodium reabsorption , reabsorption , atpase , sodium , biophysics , biochemistry , signal transduction , chemistry , microbiology and biotechnology , medicine , kidney , endocrinology , biology , enzyme , organic chemistry
Background We have demonstrated that cardiotonic steroids, such as ouabain, signaling through the Na/K‐ ATP ase, regulate sodium reabsorption in the renal proximal tubule. By direct carbonylation modification of the Pro222 residue in the actuator (A) domain of pig Na/K‐ ATP ase α1 subunit, reactive oxygen species are required for ouabain‐stimulated Na/K‐ ATP ase/c‐Src signaling and subsequent regulation of active transepithelial 22 Na + transport. In the present study we sought to determine the functional role of Pro222 carbonylation in Na/K‐ ATP ase signaling and sodium handling. Methods and Results Stable pig α1 knockdown LLC ‐ PK 1‐originated PY ‐17 cells were rescued by expressing wild‐type rat α1 and rat α1 with a single mutation of Pro224 (corresponding to pig Pro222) to Ala. This mutation does not affect ouabain‐induced inhibition of Na/K‐ ATP ase activity, but abolishes the effects of ouabain on Na/K‐ ATP ase/c‐Src signaling, protein carbonylation, Na/K‐ ATP ase endocytosis, and active transepithelial 22 Na + transport. Conclusions Direct carbonylation modification of Pro224 in the rat α1 subunit determines ouabain‐mediated Na/K‐ ATP ase signal transduction and subsequent regulation of renal proximal tubule sodium transport.