Our aim is to understand the molecular mechanisms of allosteric modulation of ligand-gated ion channels.
Neuronal ligand-gated ion channels such as the GABA(A) receptor are the essential determinants of synaptic neurotransmission, and the targets of many therapeutic agents including anesthetics. There is emerging evidence that lipids modulate ligand-gated ion channels by binding to specific sites, and that exogenous modulators such as anesthetics bind to the same or overlapping sites. Our current focus is to define the interactions of lipids and small molecule drugs in these channels, and the effects of these interactions on protein structure and function.
Recent developments in native ion mobility mass spectrometry have enabled measurements of direct binding of lipids to membrane proteins and determination of their effect on protein structure. We use a multidisciplinary approach to study lipid and small molecule modulation of pentameric ligand-gated ion channels that includes the following techniques:
Native ion mobility mass spectrometry
Chemical biology approaches including photo-affinity labeling
Patch-clamping and ion flux measurements of channels reconstituted in liposomes
Single particle cryo-EM analysis for structure determination
A Collaborative & Diverse Group
EQUIPMENT & FACILITIES
We are equipped with mass spectrometers for native ion mobility MS analysis as well as top-down and middle-down MS analysis of membrane proteins. We have an electrophysiology rig set-up for liposome patch-clamp recordings and an SX-20 stopped-flow fluorimeter for liposome flux assays. We also have access to the Biomedical Mass Spectrometry Resource, and the Center for Cellular Imaging (WUCCI) for cryo-EM analysis.
WATERS SYNAPT G1 MASS SPECTROMETER
We are equipped with this first-generation Waters Q-ToF with T-wave ion mobility separation to perform native ion mobility MS analysis of membrane proteins. This instrument is primarily used for the analysis of lipid and small molecule binding to ligand-gated ion channels.
ELECTROPHYSIOLOGY RIG FOR PATCH-CLAMPING
ROCKET ESPRESSO GIOTTO EVOLUZIONE R ESPRESSO MACHINE
From the seat of Italian fashion, the Rocket Espresso Giotto Evoluzione R brings the best of single boiler technology to Cheng Lab. Encased in polished Italian steel, the Giotto Evo's 1.8-liter heat-exchange boiler offers simultaneous brewing and steaming without the need for multiple heating elements or complex control boards. With an eye on design and the features to back it up, the Giotto Evo makes a fine coffee companion for all those late night research sessions. (St. Louis' best Kaldis coffee always on hand.)
The Washington University Center for Cellular Imaging is equipped with two Titan G3 Krios 300kV cryo-transmission electron microscopes for single particle cryo-EM tomography of vitrified samples. Our laboratory also has a GPU workstation for rapid analysis of single particle cryo-EM data using software such as Relion3.
BIOMEDICAL MASS SPECTROMETRY RESOURCE
This mass spectrometry resource in the Washington University Danforth campus is equipped with numerous mass spectrometers including instruments for high mass (native or intact protein) measurements such as the Thermo Exactive Plus EMR.
THERMO ELITE ORBITRAP MASS SPECTROMETER
In collaboration with Alex Evers, we have access to this Orbitrap mass spectrometer equipped with a Thermo Dionex nano-LC system for high sensitivity middle-down and bottom-up MS analysis of membrane proteins.
SX-20 STOPPED-FLOW FLUOROMETER
June 5, 2019
Cheng WWL, Budelier MM, Sugasawa Y, Bergdoll L, Queralt-Martín M, Rosencrans W, Rostovtseva TK, Chen ZW, Abramson J, Krishnan K, Covey DF, Whitelegge JP, Evers AS. Biochim Biophysical Acts Mol Cell Biology Lipids. 2019; 1864(10): 1269-1279.
May 28, 2019
Sugasawa Y, Bracamontes JR, Krishnan K, Covey DF, Reichert DE, Akk G, Chen Q, Tang P, Evers AS, Cheng WWL. J Steroid Biochem Mol Biol. 2019; 192:105383.
March 7, 2019
Chen ZW, Bracamontes JR, Budelier MM, Germann AL, Shin DJ, Kathiresan K, Qian MX, Manion B, Cheng WWL, Reichert DE, Akk G, Covey DF, Evers AS. PLoS Biol. 2019; 17(3):e3000157.
Budelier MM, Cheng WWL, Chen ZW, Bracamontes JR, Sugasawa Y, Krishnan K, Mydock-McGrane L, Covey DF, Evers AS. Biochim Biophys Acta Mol Cell Biol Lipids. 2019; 1864(2):128-136.
February 23, 2018
Cheng WWL, Chen ZW, Bracamontes JR, Budelier MM, Krishnan K, Shin DJ, Wang C, Jiang X, Covey DF, Akk G, Evers AS. J Biol Chem. 2018; 293(8):3013-3027.
June 2, 2017
Budelier MM, Cheng WWL, Bergdoll L, Chen ZW, Janetka JW, Abramson J, Krishnan K, Mydock-McGrane L, Covey DF, Whitelegge JP, Evers AS. J Biol Chem. 2017; 292(22):9294-9304.
February 21, 2017
Budelier MM, Cheng WW, Bergdoll L, Chen ZW, Abramson J, Krishnan K, Qian M, Covey DF, Janetka JW, Evers AS. Anal Chem. 2017; 89(4):2636-2644.
November 26, 2010
D'Avanzo N, Cheng WW, Doyle DA, Nichols CG. J Biol Chem. 2010; 285(48):37129-32.
December 24, 2010
Paynter JJ, Andres-Enguix I, Fowler PW, Tottey S, Cheng W, Enkvetchakul D, Bavro VN, Kusakabe Y, Sansom MS, Robinson NJ, Nichols CG, Tucker SJ. J Biol Chem. 2010; 285(52):40754-61.
D'Avanzo N, Cheng WW, Xia X, Dong L, Savitsky P, Nichols CG, Doyle DA. Protein Expr Purif. 2010; 71(1):115-21.
November 14, 2019
DIRECT BINDING OF PHOSPHATIDYLGLYCEROL AT SPECIFIC SITES MODULATES DESENSITIZATION OF A LIGAND-GATED ION CHANNEL.
Tong A, Petroff JT 2nd, Hsu FF, Schmidpeter PA, Nimigean CM, Sharp L, Brannigan G, Cheng WW. Elife. 2019.
April 14, 2020
Petroff JT 2nd, Tong A, Chen LJ, Dekoster GT, Khan F, Abramson J, Frieden C, Cheng WWL. Anal Chem. 2019; 92(9): 6622-6630.
September 21, 2020
Sugsawa Y, Cheng WW, Bracamontes JR, Chen ZW, Wang L, Germann AL, Pierce SR, Senneff TC, Krishnan K, Reichert DE, Covey DF, Akk G, Evers AS. Elife. 9:e55331.
The Fruits of Our Labor
Department of Anesthesiology
660 South Euclid Ave
Saint Louis, MO 63110