A5047441481- Lipid Membrane Structure and Behavior
- Ion channel regulation and function
- Nicotinic Acetylcholine Receptors Study
- Photoreceptor and optogenetics research
- Receptor Mechanisms and Signaling
- Electrochemical Analysis and Applications
- Computational Drug Discovery Methods
- Cholinesterase and Neurodegenerative Diseases
- Neuroscience and Neuropharmacology Research
- Insect and Pesticide Research
- Neurobiology and Insect Physiology Research
- Spectroscopy and Quantum Chemical Studies
- Pesticide Exposure and Toxicity
- Analytical Chemistry and Chromatography
- Venomous Animal Envenomation and Studies
- Cardiac electrophysiology and arrhythmias
- Pesticide and Herbicide Environmental Studies
- Marine Toxins and Detection Methods
- thermodynamics and calorimetric analyses
- Free Radicals and Antioxidants
- Electron Spin Resonance Studies
- Biochemical effects in animals
- Hemoglobin structure and function
- Insect Resistance and Genetics
- bioluminescence and chemiluminescence research
University of California, Davis
1990-2001
Central University of the Caribbean
2000
Columbia University
1974-1976
NOAA Physical Sciences Laboratory
1974
Stanford University
1974
MRC Laboratory of Molecular Biology
1972
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCorrelation between acetylcholine receptor function and structural properties of membranesTung Ming Fong Mark G. McNameeCite this: Biochemistry 1986, 25, 4, 830–840Publication Date (Print):February 1, 1986Publication History Published online1 May 2002Published inissue 1 February 1986https://pubs.acs.org/doi/10.1021/bi00352a015https://doi.org/10.1021/bi00352a015research-articleACS PublicationsRequest reuse permissionsArticle...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAnnular and nonannular binding sites for cholesterol associated with the nicotinic acetylcholine receptorOwen T. Jones Mark G. McNameeCite this: Biochemistry 1988, 27, 7, 2364–2374Publication Date (Print):April 5, 1988Publication History Published online1 May 2002Published inissue 5 April 1988https://pubs.acs.org/doi/10.1021/bi00407a018https://doi.org/10.1021/bi00407a018research-articleACS PublicationsRequest reuse permissionsArticle...
Functional membranes containing purified Torpedo californica acetylcholine receptor and dioleoylphosphatidylcholine (DOPC) were prepared by a cholate dialysis procedure with lipid to protein ratios of 100-400 1 (mol/mol). Spin-labeled lipids incorporated into the reconstituted native from electroplax, electron paramagnetic resonance (EPR) spectra recorded between 0 20 degrees C. The spin-labels included nitroxide derivatives stearic acid (16-doxylstearic acid), androstane,...
Acetylcholine receptors transduce the binding of acetylcholine into a change in ionic permeability cell membranes. There are several types receptors, differentiated according to their specificities for activators (agonists) and inhibitors (antagonists) permeating ions (Grundfest 1974; Rang 1974). Distinct can coexist membrane (Kehoe 1972) or may predominate at different stages cellular differentiation (Patrick et al. 1972). The molecular bases phenomenological differences as yet unknown.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTransmembrane potentials and phospholipid flip-flop in excitable membrane vesiclesMark G. McNamee Harden M. McConnellCite this: Biochemistry 1973, 12, 16, 2951–2958Publication Date (Print):July 1, 1973Publication History Published online1 May 2002Published inissue 1 July 1973https://pubs.acs.org/doi/10.1021/bi00740a001https://doi.org/10.1021/bi00740a001research-articleACS PublicationsRequest reuse permissionsArticle...
Fourier-transform infrared (FTIR) spectroscopy was used to study the secondary structure of purified Torpedo californica nicotinic acetylcholine receptor (AChR) in reconstituted membranes. Functional studies have previously demonstrated that ion channel activity requires presence both sterol and negatively charged phospholipids The present are designed test hypothesis alpha-helical AChR may be stabilized by specific lipid molecules (sterol and/or phospholipids) these alpha-helices...
Abstract Point mutations in the genes encoding acetylcholine receptor (AChR) subunits have been recognized some patients with slow‐channel congenital myasthenic syndromes (CMS). Clinical, electrophysiological, and pathological differences between these may be due to distinct effects of individual mutations. We report that a spontaneous mutation β subunit interrupts leucine ring AChR channel gate causes an eightfold increase open time severe CMS characterized by endplate myopathy extensive...
The characteristics of fatty acid inhibition acetylcholine receptor function were examined in membrane vesicles prepared from Torpedo californica electroplax. Inhibition the carbamylcholine-induced increase sodium ion permeability was correlated with bulk melting point exogenously incorporated acids. Above its temperature, a could inhibit large cation normally elicited by agonist binding to receptor. Below ineffective. None acids altered any ligand properties Inhibitory did not induce...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA minimum number of lipids are required to support the functional properties nicotinic acetylcholine receptorOwen T. Jones, James H. Eubanks, Julie P. Earnest, and Mark G. McNameeCite this: Biochemistry 1988, 27, 10, 3733–3742Publication Date (Print):May 1, 1988Publication History Published online1 May 2002Published inissue 1 1988https://pubs.acs.org/doi/10.1021/bi00410a032https://doi.org/10.1021/bi00410a032research-articleACS PublicationsRequest...
By use of a quench-flow technique to measure tracer ion flux rates in physiologically significant time domain, the kinetics activation and inactivation purified reconstituted acetylcholine receptor (AChR) were investigated. After solubilization sodium cholate, purification by affinity chromatography, reconstitution into soybean lipids, AChR from Torpedo californica displayed characteristically fast rate influx measured with 86Rb+. At 4 degrees C 1 mM carbamoylcholine (Carb) stimulated (t1/2...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffects of thio-group modifications on the ion permeability control and ligand binding properties Torpedo californica acetylcholine receptorJeffery W. Walker, Ronald J. Lukas, Mark G. McNameeCite this: Biochemistry 1981, 20, 8, 2191–2199Publication Date (Print):April 1, 1981Publication History Published online1 May 2002Published inissue 1 April 1981https://pubs.acs.org/doi/10.1021/bi00511a018https://doi.org/10.1021/bi00511a018research-articleACS...
Our previous amino acid substitutions at the postulated lipid-exposed transmembrane segment M4 of Torpedo californica acetylcholine receptor (AChR) focused on alpha C418 position. A tryptophan substitution produced a 3-fold increase in normalized macroscopic response to voltage-clamped Xenopus laevis oocytes (Lee et al., 1994). This result was explained by 23-fold decrease closing rate constant measured from single-channel analysis (Ortiz-Miranda 1996). In this study, we introduce more...
The slow-channel congenital myasthenic syndrome (SCCMS) is a dominantly inherited disorder of neuromuscular transmission characterized by delayed closure the skeletal muscle acetylcholine receptor (AChR) ion channel and degeneration junction. identification series AChR subunit mutations in SCCMS supports hypothesis that altered kinetics endplate currents this disease are attributable to abnormalities AChR. To investigate role these mutant subunits development synaptic seen SCCMS, we have...
In earlier studies with the acetylcholine receptor (AcChoR) of Electrophorus electricus rate and equilibrium constants for a model that relates ligand binding to ion translocation were determined, dependence these on concentrations carbamoylcholine acetylcholine, over 200- 5000-fold range, respectively, could be predicted. AcChoR-controlled cation flux has now been measured in Torpedo californica vesicles by using pulsed-quench-flow technique 2-msec time resolution. weight basis may contain...