Faculty

Guido Zampighi

Guido                          Zampighi                      Email: gzampighi@mednet.ucla.edu
Phone: 310-825-6430
Address: A-420 JLNRC
Research Interests: Structural organization of biological molecules (channels and pumps) by the use of electron microscopy and computer image processing.


Research Interests:

ntercellular junctions and communication A fundamental property of cells organized in tissues is their ability to communicate with ech other via highly specialized areas of plasma membrane contact, called junctions. We are studying the gap junction and the chemical synapse, two specialized junctions that mediate electrical and chemical transmission, respectively. The gap junction is composed of specialized channels containig small hydrophilic pores that span the two plasma membranes and the intervening extracellular space (the cell-to-cell channel). We are investigating the high resolution structure of the channels as well as the mechanisms of assembly, insertion and retrieval of the connexin proteins which form them. The chemical synapse is composed of a presynaptic neuron filled with small diameter vesicles that contain high concentration of neurotransmitters and a postsynaptic neuron with receptors. We are studying the mechanisms by which the synaptic vesicles attach ("dock") to the presynaptic membrane. We use structural (electron microscopy), biochemical and electrophysiological techniques in an attempt to identify, purify and characterize the channels and transporters of both junctions in an effort to further understand the mechanisms mediating cell communication.

Publications:

Zampighi, G.A, Kreman, M., Lanzavecchia, S., Turk, E., Eskandari, E., Zampighi, L., Wright, E.M. (2003). Structure of functional AQP0 channels in phospholipid bilayers J. Mol. Biol 325: 201-210

Zampighi GA (2003). Distribution of connexin50 channels and hemichannels in lens fibers: a structural approach Cell Commun Adhes 10(4-6): 265-70

Zampighi GA, Eskandari S, Hall JE, Zampighi L, Kreman M (2002). Micro-domains of AQPO in lens equatorial fibers Exp Eye Res 75(5): 505-19

Eskandari S, Zampighi GA, Leung DW, Wright EM, Loo DD (2002). Inhibition of gap junction hemichannels by chloride channel blockers J Membr Biol 185(2): 93-102

Mischel PS, Umbach JA, Eskandari S, Smith SG, Gundersen CB, Zampighi GA (2002). Nerve growth factor signals via preexisting TrkA receptor oligomers Biophys J 83(2): 968-76

Eskandari, S., Kreman, M., Kavanaugh, M.P., Wright, E.M., Zampighi, G.A (2000). A pentameric assembly of a neuronal glutamate transporter (EAAT3) Proc. Natl. Acad. Sci 97: 8641-8646

Turk E, Kim O, le Coutre J, Whitelegge JP, Eskandari S, Lam JT, Kreman M, Zampighi G, Faull KF, Wright EM (2000). Molecular characterization of Vibrio parahaemolyticus vSGLT: a model for sodium-coupled sugar cotransporters J Biol Chem 275(33): 25711-6

Zampighi GA, Eskandari S, Kreman M (2000). Epithelial organization of the mammalian lens Exp Eye Res 71(4): 415-35

Zampighi, G.A., Loo, D.D.F., Kreman, M., Eskandari, S., and Wright, EM (1999). Functional and morphological correlates of connexin50 expressed in Xenopus laevis oocytes J. Gen Physiol 113: 507-24

Eskandari S, Snyder PM, Kreman M, Zampighi GA, Welsh MJ, Wright EM (1999). Number of subunits comprising the epithelial sodium channel J Biol Chem 274(38): 27281-6

Calderon V, Lazaro A, Contreras RG, Shoshani L, Flores-Maldonado C, Gonzalez-Mariscal L, Zampighi G, Cereijido M (1998). Tight junctions and the experimental modifications of lipid content J Membr Biol 164(1): 59-69

Eskandari S, Wright EM, Kreman M, Starace DM, Zampighi GA (1998). Structural analysis of cloned plasma membrane proteins by freeze-fracture electron microscopy Proc Natl Acad Sci U S A 95(19): 11235-40

Wright EM, Hirsch JR, Loo DD, Zampighi GA (1997). Regulation of Na+/glucose cotransporters J Exp Biol 200 (Pt 2): 287-93

Konig N, Zampighi GA, Butler PJ (1997). Characterisation of the major intrinsic protein (MIP) from bovine lens fibre membranes by electron microscopy and hydrodynamics J Mol Biol 265(5): 590-602

Zampighi GA, Fisher RS (1997). Polyhedral protein cages encase synaptic vesicles and participate in their attachment to the active zone J Struct Biol 119(3): 347-59

Panayotova-Heiermann M, Eskandari S, Turk E, Zampighi GA, Wright EM (1997). Five transmembrane helices form the sugar pathway through the Na+/glucose cotransporter J Biol Chem 272(33): 20324-7

Chandy G, Zampighi GA, Kreman M, Hall JE (1997). Comparison of the water transporting properties of MIP and AQP1 J Membr Biol 159(1): 29-39

Konig, N. and Zampighi, G. (1995). Purification of bovine lens cell-to-cell channels composed of connexin44 and connexin50 J. Cell. Sci 108: 3091-3098

Mandel, L.J., Bacallao, R. and Zampighi, G. (1993). Uncoupling of the molecular "fence" and paracellular "gate" functions in epithelial tight junctions Nature 361: 552-555