Departments And Divisions
- Department of Biochemistry and Molecular Biophysics
- Department of Physiology & Cellular Biophysics
- Higgins Professor of Biochemistry and Molecular Biophysics
- Professor of Neurology
- Professor of Physiology & Cellular Biophysics
- Director, Center for Molecular Recognition
We try to understand how receptors and channels recognize specific ligands, how the binding of these ligands is converted into the opening of ion-conducting channels (or into an interaction with GTP-binding proteins), how the selectivity of the channels is determined, and how ions are conducted through the channels. The main approaches are to identify the residues that line the binding sites and conduction pathways, to determine the three-dimensional structures, to locate the critical residues in these three-dimensional structures, and to detect changes in the structures corresponding to changes in functional states. To reach these goals, we use the methods of protein chemistry, molecular biology, and electrophysiology.
- 630 West 168th Street
New York, NY 10032
- (212) 305-5778
- Biophysics/Ion Channels
Karlin A (2015) Membrane potential and Ca2+ concentration dependence on pressure and vasoactive agents in arterial smooth muscle: A model. J. Gen. Physiol. 146:79–96 www.jgp.org/cgi/doi/10.1085/jgp.201511380.
Liu G, Zakharov SI, Yao Y, Marx SO, and Karlin, A (2015) Positions of the cytoplasmic end of BK alpha S0 helix relative to S1-S6 and of beta1 TM1 and TM2 relative to S0-S6. J Gen Physiol 145:185-199. doi:10.1085/jgp.201411337.
Niu X, Liu G, Wu RS, Chudasama N, Zakharov SI, et al. (2013) Orientations and proximities of the extracellular ends of transmembrane helices S0 and S4 in open and closed BK potassium channels. PLoS ONE 8(3): e58335. doi:10.1371/journal.pone.0058335.
Chan, P.J., Osteen, J.D., Xiong, D., Bohnen, M.S., Doshi, D., Sampson, K.J., Marx, S.O., Karlin, A., and Kass, R.S. (2012) Characterization of KCNQ1 atrial fibrillation mutations reveals distinct dependence on KCNE1. J. Gen Physiol. 139:135-144.
Liu, G., Niu, X., Wu, R.S., Chudasama, N., Yao, Y., Jin, X., Weinberg, R., Zakharov, S.I., Motoike, H., Marx, S.O., and Karlin, A. (2010) Location of modulatory subunits in BK potassium channels. J. Gen. Physiol. 135:449-459.
Wu, R.S., Chudasama, N., Zakharov, S.I., Doshi, D., Motoike, H., Liu, G., Yao, Y., Niu, X., Deng, S.-X., Landry, D.W., Karlin, A., and Marx, S.O. (2009) Location of the beta 4 transmembrane helices in the BK potassium channel. J. Neurosci. 29:8321-8328.
Chung, D.Y., Chan, P. J., Bankston, J.R., Yang, L., Liu, G., Marx, S.O., Karlin, A., Kass, R.S. (2008) Location of KCNE1 relative to KCNQ1 in the IKS potassium channel by disulfide crosslinking of substituted cysteines. Proc. Natl. Acad. Sci. USA 106:743-748.
Liu, G., Zakharov, S., Yang., L., Wu, R., Deng, S., Landry, D., Karlin, A., Marx, S. (2008) Locations of the beta1 transmembrane helices in the BK potassium channel. Proc. Natl. Acad. Sci. USA 105:10727-10732.
Liu, G., Zakharov, S., Yang., L., Deng, S., Landry, D., Karlin, A., Marx, S. (2008) Position and role of the BK channel subunit S0 helix inferred from disulfide crosslinking. J. Gen. Physiol 131: 537-548.
Li, Y., Karlin, A., Loike, J.D., and Silverstein, S. C. (2004) A critical concentration of neutrophils required to block growth of Staphylococcus epidermidis in fibrin gels and of E. coli in rabbit dermis. J. Exp. Med.200:613-622.
Li, J.,Shi, L., and Karlin, A. (2003) A photochemical approach to the lipidaccessibility of engineered cysteinyl residues. Proc. Natl. Acad. Sci. USA 100: 886-891.
Yu, Y., Shi, L., and Karlin, A. (2003). Structural effects of quinacrine binding in the open channel of theacetylcholine receptor. Proc. Natl. Acad. Sci. USA 100: 3907-3912.
Karlin, A. (2003) Nicotinic acetylcholine receptors: Probing functionally significant structural changes with site directed reactions. In “Cholinergic Mechanisms: Function and Dysfunction”, A. Fisher and H. Soreq, eds, chapter 2.
Karlin, A. (2002). Emerging structure of the nicotinic acetylcholine receptors. Nature Rev. Neurosci. 3: 102-114.
Li,J., Xu, Q., Cortes, D. M., Perozo, E., Laskey, A., and Karlin, A.(2002) Reactions of cysteines substituted in the amphipathic N-terminaltail of a bacterial potassium channel with hydrophilic and hydrophobicmaleimides. Proc. Natl. Acad. Sci. USA 99: 11605-11610.
Wilson, G.G., and Karlin, A. (2001). Acetylcholine receptor channelstructure in the resting, open, and desensitized states probed with thesubstituted-cysteine-accessibility method. Proc. Natl. Acad. Sci. USA98: 1241-1248.