The distribution, dynamics, internalization, and retrograde axonal traffic of a fusion protein
composed of green fluorescent protein (GFP) and the atoxic C-terminal fragment of tetanus
toxin (TTC) were studied after its in vivo injection. Confocal microscopy and immunogold
electron microscopy revealed that the fusion protein (GFP-TTC) rapidly clustered in motor
nerve terminals of the neuromuscular junction. Clathrin-coated pits, and axolemma
infoldings located between active zones appeared to be involved in the internalization of the …