FXYD2 and Na,K-ATPase expression in isolated human proximal tubular cells: disturbed upregulation on renal hypomagnesemia?

ABSTRACT: Autosomal dominant renal hypomagnesemia (OMIM 154020), associated with hypocalciuria, has been linked to a 121G to A mutation in the FXYD2 gene. To gain insight into the molecular mechanisms linking this mutation to the clinical phenotype, we studied isolated proximal tubular cells from urine of a patient and a healthy subject. Cells were immortalized and used to assess the effects of hypertonicity-induced overexpression of FXYD2 on amount, activity and apparent affinities for Na(+), K(+) and ATP of Na,K-ATPase. Both cell lines expressed mRNA for FXYD2a and FXYD2b, and patient cells contained both the wild-type and mutated codons. FXYD2 protein expression was lower in patient cells and could be increased in both cell lines upon culturing in hyperosmotic medium but to a lesser extent in pat

SUBMITTER: Cairo ER 

PROVIDER: S-EPMC2776943 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature