Anterograde Monosynaptic Transneuronal Tracers Derived from Herpes Simplex Virus 1 strain H129
作者单位：State Key Laboratory of Virology CAS Center for Excellence in Brain Science and Intelligence Technology (CEBSIT) Wuhan Institute of Virology Chinese Academy of Sciences State Key Laboratory of Membrane Biology School of Life Sciences Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Brain Research Center Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences
会议名称：《中国神经科学学会第十二届全国学术会议》
会议日期：2017年
学科分类：0710[理学-生物学] 07[理学] 071006[理学-神经生物学]
关 键 词：Herpes simplex virus type 1(HSV-1) H129 strain anterograde neuronal tracer H129-ΔTK-tdT monosynaptic H129-G4 multisynaptic
摘 要：Objective Herpes simplex virus type 1 strain 129（H129） has represented a promising anterograde neuronal circuit tracing tool, which complements the existing retrograde tracers. However, the current H129 derived tracers are multisynaptic, neither bright enough to label the details of neurons nor capable of determining direct projection targets as monosynaptic tracer. The present study is to introduce an improved multisynaptic anterograde tracer H129-G4 with strong labeling intensity, and a novel mono-synaptic anterograde tracer H129-ΔTK-td T. Methods Based on the bacterial artificial chromosome of H129, we have generated a serial of recombinant viruses for neuronal circuit tracing. Among them, H129-G4 was obtained by inserting binary tandemly connected GFP cassettes into the H129 genome, and H129-ΔTK-td T was obtained by deleting the thymidine kinase（TK） gene and adding td Tomato coding gene to the H129 genome. Then the obtained viral tracers were tested in vitro and in vivo for the tracing capacity. Results H129-G4 is capable of transmitting through multiple synapses, labeling the neurons by green florescent protein, and visualizing the morphological details of the labeled neurons. H129-ΔTK-td T neither replicates nor spreads in neurons alone, but transmits to and labels the postsynaptic neurons with td Tomato in the presence of complementary expressed TK from a helper virus. H129-ΔTK-td T is also capable to map the direct projectome of the specific neuron type in the given brain regions in Cre transgenic mice. In the tested brain regions where circuits are well known, the H129-ΔTK-td T tracing patterns are consistent with the previous results. Conclusion With the assistance of the helper virus complimentarily expressing TK, H129-ΔTK-td T replicates in the initially infected neuron, transmits anterogradely through one synapse, and labeled the postsynaptic neurons with td Tomato. The H129-ΔTK-td T anterograde monosynaptic tracing system offers a useful tool for mappi