Skip to main content
. Author manuscript; available in PMC: 2011 Aug 26.
Published in final edited form as: Neuron. 2010 Aug 26;67(4):562–574. doi: 10.1016/j.neuron.2010.08.001

Figure 1. Single Cell Tracing Strategy.

Figure 1

(A) A single neuron is electroporated with plasmids (colored circles) coding for a fluorescent marker (e.g., pCAG-mCherry), the TVA receptor (pCMMP-TVA800), and the rabies glycoprotein (pHCMV-RabiesG).

(B) After 1–3 days, SADΔG-XFP(EnvA) virus is applied to the tissue, and infects only the electroporated neuron, since no other cells express the EnvA receptor, TVA (red indicates electroporated marker expression; black symbols, TVA and rabies glycoprotein (G)). As the virus replicates in the host neuron, it expresses XFP from the rabies genome, labeling the neuron (green in (C); merge yellow with electroporated marker).

(C) After 3–6 days, the tissue is fixed with paraformaldehyde after time has elapsed for transsynaptic infection (dotted arrow) and expression of the rabies virus and the tissue is visualized with fluorescence microscopy. The virus only transsynaptically infects and labels direct monosynaptic, presynaptic inputs (green) to the original host neuron, and not secondary connections (red crosses) because rabies glycoprotein, which is necessary for transsynaptic spread, is expressed only in the electroporated neuron. The schematic shows the timeline and gene constructs used for the experiment in Figure 4.