FRET analysis reveals a critical conformational change within the Na,K-ATPase alpha1 subunit N-terminus during GPCR-dependent endocytosis.
Dopamine is a major regulator of sodium reabsorption in proximal tubule epithelia. It induces the endocytosis of plasma membrane Na,K-ATPase molecules, and this results in a reduced capacity of the cells to transport sodium. Dopamine induces the phosphorylation of Ser-18 in the alpha1-subunit of Na,K-ATPase. Fluorescence resonance energy transfer analysis of cells expressing YFP-alpha1 and beta1-CFP reveals that treatment of the cells with dopamine increases energy transfer between CFP and YFP. This is consistent with a protein conformational change that results in the N-terminal end of alpha1 moving closer to the internal face of the plasma membrane.
Efendiev
Riad
R
Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, 4800 Calhoun Road, Houston, TX 77204-5037, USA. refendiev@uh.edu
Cinelli
Angel R
AR
Leibiger
Ingo B
IB
Bertorello
Alejandro M
AM
Pedemonte
Carlos H
CH
D000470:Alkaloids; D000730:Androstadienes / Q000494:pharmacology; D000818:Animals; D053119:Benzophenanthridines; D002478:Cells, Cultured; D004298:Dopamine / Q000494:pharmacology; D004705:Endocytosis / Q000187:drug effects; D031541:Fluorescence Resonance Energy Transfer; D009893:Opossums; D010617:Phenanthridines / Q000494:pharmacology; D011487:Protein Conformation / Q000187:drug effects; D021122:Protein Subunits / Q000737:chemistry* / Q000378:metabolism; D051381:Rats; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry* / Q000378:metabolism*; D000077191:Wortmannin
D000470:Alkaloids; D000730:Androstadienes; D053119:Benzophenanthridines; D010617:Phenanthridines; D021122:Protein Subunits; D043562:Receptors, G-Protein-Coupled; C016299:chelerythrine; C499075:Atp1a1 protein, rat; D000254:Sodium-Potassium-Exchanging ATPase; D004298:Dopamine; D000077191:Wortmannin