Journal of Neuroscience, Vol 3, 659-672, Copyright © 1983 by Society for Neuroscience
Transplantation of cricket sensory neurons to ectopic locations: arborizations and synaptic connections
RK Murphey, JP Bacon, DS Sakaguchi and SE Johnson
The cerci (abdominal sensory appendages) of crickets were transplanted to a
leg stump after amputating the leg. Single identifiable cercal afferents
were stained and found to regenerate into the host thoracic ganglia. A
given neuron always arborizes in the same area of neuropil of the foreign
ganglion and is distinctive in this property from other identified neurons.
Taken as a whole, the results show that the afferents from the ectopic
cercus are spatially ordered, the destination of a particular afferent
within the ganglion being correlated with the location of its sensory cell
body on the cercal surface. This is the case for the pro-, meso-, and
metathoracic ganglion and the topography of these ectopic projections bears
some resemblance to the normal projections found in the terminal ganglion.
Thus the insect segmental ganglion seems to possess a set of markers which
are interpretable by all afferent neurons, and this organization is
repeated in each ganglion. The ectopic afferents make functional synaptic
connections with intersegmental interneurons, one of which is described
anatomically here. However, the ectopic afferents do not, as had previously
been reported, make functional connections with the medial giant or lateral
giant interneuron (the normal targets of cercal sensory neurons in the
terminal ganglion).