Overexpression of the Na+,K+-ATPase α1 Subunit Increases Na+,K+-ATPase Function in A549 Cells

P Factor, C Senne, V Dumasius, K Ridge… - American journal of …, 1998 - atsjournals.org
P Factor, C Senne, V Dumasius, K Ridge, H Ari Jaffe, B Uhal, Z Gao, J Iasha Sznajder
American journal of respiratory cell and molecular biology, 1998atsjournals.org
We hypothesized that viral mediated transfer of Na+, K+-ATPase subunit genes to alveolar
epithelial cells to overexpress Na+, K+-ATPase could increase Na+, K+-ATPase function.
We produced replication-deficient human type 5 adenoviruses that contained
cytomegalovirus (CMV)-driven cDNAs for the rat α1 and β1 subunits of Na+, K+-ATPase
(AdMRCMVα1 and AdMRCMVβ1, respectively). These viruses were used to transduce
human adenocarcinoma cells (A549) in culture. Na+, K+-ATPase function was increased by …
We hypothesized that viral mediated transfer of Na+,K+-ATPase subunit genes to alveolar epithelial cells to overexpress Na+,K+-ATPase could increase Na+,K+-ATPase function. We produced replication-deficient human type 5 adenoviruses that contained cytomegalovirus (CMV)-driven cDNAs for the rat α1 and β1 subunits of Na+,K+-ATPase (AdMRCMVα1 and AdMRCMVβ1, respectively). These viruses were used to transduce human adenocarcinoma cells (A549) in culture. Na+,K+-ATPase function was increased by 2.5-fold in the AdMRCMVα1-infected cells. Sham and AdMRCMVβ1-infected cells, and cells infected by a CMV-driven β-galactosidase-expressing adenovirus, had no increases in Na+,K+-ATPase activity. A549 cells infected with multiplicities of infection of 10–200 of AdMRCMVα1 demonstrated expression of a rat α1 mRNA and increased α1 protein; no change in β1 message or protein was noted. Ouabain sensitivity was measured in A549 cells following infection with AdMRCMVα1. In contrast to controls, AdMRCMVα1-infected cells demonstrated two IC50s. The first was similar to the IC50s of the controls; the second IC50 was 2 logs greater than the first, consistent with the presence of both the rat and human α1 isozymes. These results demonstrate for the first time that adenoviruses can be used to augment Na+,K+-ATPase function.
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