Hybrid tetanus toxin proteins migrating retrograde and trans-synaptically into the CNS

摘要

The non-toxic proteolytic C fragment of tetanus toxin (TTC peptide) has the same ability to bind nerve cells and be retrogradely transported through a synapse as the native toxin. A hybrid protein encoded by the lacZ-TTC gene fusion retains the biological functions of both proteins in vivo, i.e. retrograde transynaptic transport of the TTC fragment and -gal enzymatic activity. After intramuscular injection, enzymatic activity could be detected in motoneurons and connected neurons of the brainstem areas. This strategy is useful for the delivery of a biological activity to neurons from the periphery to the central nervous system. Such a hybrid protein can also be used to map synaptic connections between neural cells.