An HSV-1-H129 amplicon tracer system for rapid and efficient monosynaptic anterograde neural circuit tracing.

Xiong, Feng; Yang, Hong; Song, Yi-Ge; Qin, Hai-Bin; Zhang, Qing-Yang; Huang, Xian; Jing, Wei; Deng, Manfei et al. · Nat Commun · 2022

basic_science · Level V

Where this comes from

Abstract

Monosynaptic viral tracers are essential tools for dissecting neuronal connectomes and for targeted delivery of molecular sensors and effectors. Viral toxicity and complex multi-injection protocols are major limiting application barriers. To overcome these barriers, we developed an anterograde monosynaptic H129<sub>Amp</sub> tracer system based on HSV-1 strain H129. The H129<sub>Amp</sub> tracer system consists of two components: an H129-dTK-T2-pac<sup>Flox</sup> helper which assists H129<sub>Amp</sub> tracer's propagation and transneuronal monosynaptic transmission. The shared viral features of tracer/helper allow for simultaneous single-injection and subsequent high expression efficiency from multiple-copy of expression cassettes in H129<sub>Amp</sub> tracer. These improvements of H129<sub>Amp</sub> tracer system shorten experiment duration from 28-day to 5-day for fast-bright monosynaptic tracing. The lack of toxic viral genes in the H129<sub>Amp</sub> tracer minimizes toxicity in postsynaptic neurons, thus offering the potential for functional anterograde mapping and long-term tracer delivery of genetic payloads. The H129<sub>Amp</sub> tracer system is a powerful tracing tool for revealing neuronal connectomes.

Medical subject headings