Document Type


Publication Date

Fall 10-11-2013


Cardiotonic steroids (such as ouabain) signaling through Na/K-ATPase regulate sodium reabsorption in the renal proximal tubule. We report here that reactive oxygen species are required to initiate ouabain-stimulated Na/K-ATPase·c-Src signaling. Pretreatment with the antioxidant N-acetyl-L-cysteine prevented ouabain-stimulated Na/K-ATPase·c-Src signaling, protein carbonylation, redistribution of Na/K-ATPase and sodium/proton exchanger isoform 3, and inhibition of active transepithelial 22Na+ transport. Disruption of the Na/K-ATPase·c-Src signaling complex attenuated ouabain-stimulated protein carbonylation. Ouabain-stimulated protein carbonylation is reversed after removal of ouabain, and this reversibility is largely independent of de novo protein synthesis and degradation by either the lysosome or the proteasome pathways. Furthermore, ouabain stimulated direct carbonylation of two amino acid residues in the actuator domain of the Na/K-ATPase α1 subunit. Taken together, the data indicate that carbonylation modification of the Na/K-ATPase α1 subunit is involved in a feed-forward mechanism of regulation of ouabain-mediated renal proximal tubule Na/K-ATPase signal transduction and subsequent sodium transport.


The version of record is available from the publisher at This research was originally published in the Journal of Biological Chemistry. Yan Y, AP Shapiro, S Haller, V Katragadda, L Liu, J Tian, V Basrur, D Malhtra, ZJ Xie, N Abraham, JI Shapiro, and J Liu. Involvement of reactive oxygen species in a feed-forward mechanism of Na/K-ATPase-mediated signaling transduction. Journal of Biological Chemistry. 2013; 288:34249-58. © The American Society for Biochemistry and Molecular Biology. DOI 10.1074/jbc.M113.461020