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Faculty Profile

Robert Duvoisin, Ph.D.

Associate Professor

Primary Affiliation

SOM-Physiology & Pharmacology Department

Program Affiliation

Neuroscience Graduate Program
Physiology & Pharmacology

Summary of Current Research

Glutamate is the major excitatory neurotransmitter in the vertebrate central nervous system. In addition to its role in normal brain processes, such as learning and memory, imbalances in glutamatergic function can result in excitotoxic neuronal cell death, epileptic seizures or psychiatric diseases. Glutamate stimulates two classes of receptors: 1) glutamate-gated ion channels, so called ionotropic receptors, which are subdivided into the NMDA, AMPA, and kainate types, and 2) G protein-coupled metabotropic glutamate receptors (mGluRs). Research in the Duvoisin lab is currently focused on group-III mGluRs, a subset of related mGluRs that are selectively activated by L-2-amino-4-phosphonobutyric acid (L-AP4, also abbreviated APB). Group-III mGluRs comprise mGluR4, -R6, -R7, and -R8.

mGluR6 is nearly exclusively expressed in the retina, in the tips of ON-bipolar cells dendrites, where it mediates the depolarizing response of ON-bipolar cells to light. Since all photoreceptor cells (rods and cones) release glutamate, the opposite responses of the second-order ON- and OFF-bipolar cells is generated by their expression of mGluR6 and AMPA/kainate receptors, respectively. One project in the laboratory is to explore the regulation of the signaling cascade activated by mGluR6.

The distribution and function of the other group-III mGluRs, mGluR4, -R7, and -R8, is less well understood. In the brain, group-III receptors are generally presynaptic and reduce glutamate release, thus providing negative feedback. Presynaptic mGluRs also occur on GABAergic terminals, so called heteroreceptors, and depress GABA release when stimulated by glutamate released from a nearby terminal. The distribution and function of group-III mGluRs in the retina is being studied.

The Duvoisin lab has generated mice deficient for mGluR8 and found that these mice are overweight and have increased measures of anxiety compared to wild-type mice. In collaboration with Dr. Jacob Raber (Dept. Behavioral Neuroscience), the role of mGluR8 in anxiety is being examined.

Recent Publications

  • Puthussery T., Gayet-Primo J., Pandey S., Duvoisin R.M., Taylor W.R. (2009) Differential loss and preservation of glutamate receptor function in bipolar cells in the rd10 mouse model of retinitis pigmentosa. Eur J Neurosci. 29:1533-1542.
  • Morgans C.W., Liu W., Wensel T.G., Bearnot B., Perez-Leon J.A., Brown R.L., Duvoisin R.M. (2007) Gbeta5-RGS complexes co-localize with mGluR6 in retinal ON-bipolar cells. Eur J Neurosci. 26:2899-2905.
  • Quraishi S., Gayet J., Morgans C.W., Duvoisin R.M. (2007) Distribution of group-III metabotropic glutamate receptors in the retina. J Comp Neurol. 501:931-943.
  • Wu G., Glickstein S., Liu W., Fujita T., Li W., Yang Q., Duvoisin R., Wan Y. (2007) The anaphase-promoting complex coordinates initiation of lens differentiation. Mol Biol Cell. 18:1018-1029.
  • Adamus G, Webb S, Shiraga S, Duvoisin RM (2006): Anti-recoverin antibodies induce an increase in intracellular calcium, leading to apoptosis in retinal cells. J Autoimmun. 26, 146-153.
  • Duvoisin RM, Morgans CW, Taylor WR (2005a): The mGluR6 receptors in the retina: Analysis of a unique G-protein signaling pathway. Cellscience Rev. 2, 225-243.
  • Duvoisin RM, Zhang C, Pfankuch TF, O'Connor H, Gayet-Primo J, Quraishi S, Raber J (2005b): Increased measures of anxiety and weight gain in mice lacking the group III metabotropic glutamate receptor mGluR8. Eur J Neurosci. 22, 425-436.
  • Francesconi A, Duvoisin RM (2004): Divalent cations modulate the activity of metabotropic glutamate receptors. J Neurosci Res. 75, 472-479.
  • Francesconi A, Duvoisin RM (2002): Alternative splicing unmasks dendritic and axonal targeting signals in metabotropic glutamate receptor 1. J Neurosci. 22, 196-205.

Education

  • Ph.D., University of Geneva, Switzerland, 1987

Previous Positions

  • Postdoctoral Fellow, The Salk Institute, La Jolla, CA, 1987-1991
  • Associate Professor, Cornell University Medical College, New York, NY, 1991-2001

Non-Academic Interests

Preceptor Rotations

Academic Term Available
Winter 2009 Maybe
Spring 2009 Maybe
Summer 2009 Maybe

Faculty Mentorship

Dr. Duvoisin might be available as a mentor for 2008-2009.

Dr. Duvoisin might be available as a mentor for 2009-2010.

Date Updated: 09/16/2007