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bioRxiv · 10.1101/2023.06.20.545789

Recombinase-Independent AAV for Anterograde Transsynaptic Tracing

Faress, I.·Khalil, V.·Yamamoto, H.·Sajgo, S.·Yonehara, K.·Nabavi, S.
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Abstract

Viral transsynaptic labeling has become indispensable for investigating the functional connectivity of neural circuits. Adeno-associated virus serotype 1 (AAV1) allows for anterograde transneuronal labeling and manipulation of postsynaptic neurons. However, it is limited to delivering an AAV1 expressing a recombinase which relies on using transgenic animals or genetic access to postsynaptic neurons. We reasoned that a strong expression level could overcome this limitation. To this end, we used a self-complementary AAV1 (scAAV1) under a strong promoter (CAG). We demonstrated the anterograde transneuronal efficiency of scAAV1 by delivering a fluorescent marker in mouse retina-superior colliculus and thalamic-amygdala pathways in a recombinase-independent manner. In addition to investigating neuronal connectivity, scAAV1.CAG may be suitable for functional manipulation and imaging.

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Faress, I., Khalil, V., Yamamoto, H., Sajgo, S., Yonehara, K., Nabavi, S.. 2023-06-22. Recombinase-Independent AAV for Anterograde Transsynaptic Tracing. https://doi.org/10.1101/2023.06.20.545789

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