title: Structure of the Na,K-ATPase regulatory protein FXYD2b in micelles: implications for membrane-water interfacial arginines.
abstract: FXYD2 is a membrane protein responsible for regulating the function of the Na,K-ATPase in mammalian kidney epithelial cells. Here we report the structure of FXYD2b, one of two splice variants of the protein, determined by NMR spectroscopy in detergent micelles. Solid-state NMR characterization of the protein embedded in phospholipid bilayers indicates that several arginine side chains may be involved in hydrogen bond interactions with the phospholipid polar head groups. The structure and the NMR data suggest that FXYD2b could regulate the Na,K-ATPase by modulating the effective membrane surface electrostatics near the ion binding sites of the pump.
authors.affiliation: Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Xiao-Min
authors.initials: XM
authors.lastname: Gong
authors.affiliation: Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Yu
authors.affiliation: Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yao
authors.affiliation: Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA. Electronic address: fmarassi@sbmri.org.
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Marassi
mesh_terms: D000595:Amino Acid Sequence; D001120:Arginine / Q000737:chemistry*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D056004:Molecular Dynamics Simulation; D008969:Molecular Sequence Data; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D055672:Static Electricity
chemical_list: D008823:Micelles; D001120:Arginine; C416502:FXYD2 protein, human; D000254:Sodium-Potassium-Exchanging ATPase
keywords: FXYD; K-ATPase; NMR; Na; membrane protein; structure