Probing the interaction of the potassium channel modulating KCNE1 in lipid bilayers via solid-state NMR spectroscopy
| Autor: | Indra D. Sahu, Carole Dabney-Smith, Rongfu Zhang, Gary A. Lorigan, Sergey Maltsev, Raven G. Comer |
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| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
congenital hereditary and neonatal diseases and abnormalities Magnetic Resonance Spectroscopy Potassium ion homeostasis Potassium Lipid Bilayers Analytical chemistry Phospholipid chemistry.chemical_element Article 03 medical and health sciences chemistry.chemical_compound Humans General Materials Science Amino Acid Sequence Lipid bilayer POPC Micelles 030102 biochemistry & molecular biology Vesicle General Chemistry Potassium channel Kinetics 030104 developmental biology chemistry Solid-state nuclear magnetic resonance Potassium Channels Voltage-Gated Biophysics cardiovascular system |
| Zdroj: | Magnetic resonance in chemistry : MRC. 55(8) |
| ISSN: | 1097-458X |
| Popis: | KCNE1 is known to modulate the voltage-gated potassium channel α subunit KCNQ1 to generate slowly activating potassium currents. This potassium channel is essential for the cardiac action potential that mediates a heartbeat as well as the potassium ion homeostasis in the inner ear. Therefore, it is important to know the structure and dynamics of KCNE1 to better understand its modulatory role. Previously, the Sanders group solved the three-dimensional structure of KCNE1 in LMPG micelles, which yielded a better understanding of this KCNQ1/KCNE1 channel activity. However, research in the Lorigan group showed different structural properties of KCNE1 when incorporated into POPC/POPG lipid bilayers as opposed to LMPG micelles. It is hence necessary to study the structure of KCNE1 in a more native-like environment such as multi-lamellar vesicles. In this study, the dynamics of lipid bilayers upon incorporation of the membrane protein KCNE1 were investigated using (31) P solid-state nuclear magnetic resonance (NMR) spectroscopy. Specifically, the protein/lipid interaction was studied at varying molar ratios of protein to lipid content. The static (31) P NMR and T1 relaxation time were investigated. The (31) P NMR powder spectra indicated significant perturbations of KCNE1 on the phospholipid headgroups of multi-lamellar vesicles as shown from the changes in the (31) P spectral line shape and the chemical shift anisotropy line width. (31) P T1 relaxation times were shown to be reversely proportional to the molar ratios of KCNE1 incorporated. The (31) P NMR data clearly indicate that KCNE1 interacts with the membrane. Copyright © 2017 John Wiley & Sons, Ltd. |
| Databáze: | OpenAIRE |
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