Research Summary:
My lab is interested in the role of glial cells in the formation and maintenance of synapses in the nervous system. For this purpose we study the simplest of all synapses, the neuromuscular junction where our previous work suggests these glial cells (Schwann cells) guide and induce the growth of axons and control several aspects of synaptic structure. Our primary approach is to use vital imaging in the living animal. Because we made transgenic mice that express different colors of green fluorescent protein in neurons and glial cells, we can repeatedly visualize these cells using fluorescence microscopy and determine how they behave during development and during reformation of synaptic connections following nerve injury. We are also preparing transgenics in which we can inducibly control expression of transgenes, including dominant negatives for signaling molecules, to analyze cell-cell interactions involving glial cells.

Vital images of a neuromuscular junction in a mouse - A single neuromuscular junction was imaged at two times from a living mouse, each set of images separated by 30 days. Acetylcholine receptors (AChR) were labeled with rhodamine bungarotoxin. Schwann cells (SC) were labeled by transgenic expression of green fluorescent protein (GFP). Axons were labeled by transgenic expression of cyan fluorescent protein (CFP). This junction, unlike junctions following nerve damage or during aging, does not change significantly over this time period.