Predoctoral Students:
Michele Nachman-Clewner
Peter Alfinito
Mohamad Khodair
 

Areas of interest: degeneration and regeneration of adult neurons, synaptic plasticity, synaptogenesis
 

Current research projects: My laboratory is using an in vitro system to examine synaptic function and regeneration of the mature central nervous system. We isolate functional, fully differentiated neurons from the adult vertebrate eye and maintain them in defined culture conditions. Sensory neurons, short interneurons, and projection neurons are all able to regrow neurites and reform functional synapses in vitro. Projects are currently under way to determine the specificity of synapse reformation, the effects of calcium on this regeneration, the signal transduction pathways which control cytoskeletal reorganization and changes in gene expression, and the effects of ageing on regenerative capabilities. Much of the work is done on photoreceptors since degeneration of these sensory neurons is a major cause of blindness. The techniques used include cell culture, immunocytochemistry, a variety of light microscopic techniques including confocal laser scanning microscopy, electron microscopy , video time-lapse photography, and image processing. And just recently we have begun to use a new micromanipulation technique, optical tweezers, to form specific groups of interacting neurons in culture. In the long term, the goal of this work is not only to understand more about the capabilities of central synapses, but to use this information in suggesting clinical solutions for central nervous system repair and transplantation.
 

Representative Publications:
 

Mandell, J.W., Townes-Anderson, E., Czernik, A.J., Cameron, R., Greengard, P. and P. DeCamilli. Localization of the synapsins in the vertebrate retina: Absence from ribbon synapses and heterogeneous distribution among conventional synapses. Neuron 5:19-33, 1990. 
 

Mandell, J.W., MacLeish, P.R. and E. Townes-Anderson. Process outgrowth and synaptic varicosity formation by adult photoreceptors in vitro. J. Neurosci. 13:3533-3548, 1993.
 

Townes-Anderson, E. Intersegmental fusion in vertebrate rod photoreceptors. Rod cell structure revisited. Invest. Ophthal. Vis. Sci. 36:1918-1933, 1995.
 

Sherry, D.M., St. Jules, R.S. and E. Townes-Anderson. Morphological and neurochemical target selectivity of regenerating adult photoreceptors in vitro. J. Comp. Neurol. 376:476-488, 1996.
 

Nachman-Clewner, M. and E. Townes-Anderson. Injury-induced remodeling and regeneration of the ribbon presynaptic terminal in vitro. J. Neurocytol. 25:597-613, 1996.
 

Townes-Anderson, E., Colantonio, A. and R. S. St. Jules. Age-related changes in the tiger salamander retina. Exp. Eye Research 66:653-667, 1998.
 

Townes-Anderson, E., R.S. St. Jules, D.M. Sherry, J. Lichtenberger, and M. Hassanain. Micromanipulation of retinal neurons by optical tweezers. Molecular Vision 4:12,1998.