F A C U L T Y   P R O F I L E 

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Higgins Professor of Biochemistry & Molecular Biophysics, Physiology & CellularBiophysics, and Neurology

The function of receptors in terms of molecular structures.

Office: Physicians & Surgeons | 11th floor | Room 401
Telephone: 212.305.5778
Fax: 212.305.5594

Current Research

Current research is on the structure and function of receptors and ion channels, approached by mutagenesis, chemical modification, and electrophysiological probing of function. In particular, one target has been the large-conductance, calcium- and voltage- activated potassium channel (BK). A more recently started effort is on the nature of signaling among multiple receptors and channels in intact arterial smooth muscle cells. Transgenic and photochemical methods are used to determine which receptors and channels signal to each other within microdomains of dimensions of 50 nm or less. Finally, the integration of receptors, channels, transporters, and signaling cascades are being modeled mathematically, in the first instance as a model of an arterial smooth muscle cell. The theoretical and experimental approaches are mutually supportive.

Selected Publications

Karlin, A. 2002. Emerging structure of the nicotinic acetylcholine receptors. Nature Reviews Neuroscience 3: 102-114.

Liu, G., Zakharov, S., Yang., L., Deng, S., Landry, D., Karlin, A., Marx, S. (2008) Position and role of the BK channel alpha subunit S0 helix inferred from disulfide crosslinking. J. Gen. Physiol 131: 537-548.

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.

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.

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 beta4 transmembrane helices in the BK potassium channel. J. Neurosci. 29:8321-8328. PMCID:PMC2737688

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 β subunits in BK potassium channels. J. Gen. Physiol. 135:449-459; PMCID: PMC2860586

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 PMCID: PMC3269792

Wu RS, Liu G, Zakharov SI, Chudasama N, Motoike H, Karlin A, Marx SO. (2013 ) Positions of β2 and β3 subunits in the large-conductance calcium- and voltage-activated BK potassium channel. J Gen Physiol. 141:105-17. PMCID:PMC3536527

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 PMCID: PMC3589268