Gamma structural variants differentially regulate Na,K-ATPase properties.
Renal Na,K-ATPase is tightly bound to a small regulatory protein, the gamma subunit (FXYD2). In rat, it occurs in two splice variants with different N-termini. Immunolocalization on kidney sections revealed distinct distribution of the gamma splice variants along the rat nephron. Where coexpressed, they coimmunoprecipitated with each other along with the alpha subunit, suggesting assembly in oligomeric complexes. Functional consequences of association with gamma were monitored in stably transfected NRK-52E cells. The outcome was that splice variants can differentially modulate the major intrinsic properties of the Na,K-ATPase under normal and stress-related conditions. The data imply an adaptive physiological mechanism of regulation of renal Na,K-ATPase through modulation of pump properties, gene expression, or both.
Arystarkhova
Elena
E
Neuroscience Center, Massachusetts General Hospital, Charlestown 02129, USA. aristark@helix.mgh.harvard.edu
Wetzel
Randall K
RK
D000818:Animals; D002460:Cell Line; D014644:Genetic Variation; D007700:Kinetics; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D014162:Transfection
D011994:Recombinant Proteins; C498817:Fxyd2 protein, rat; D000254:Sodium-Potassium-Exchanging ATPase