A Novel Retrograde AAV Variant for Functional Manipulation of Cortical Projection Neurons in Mice and Monkeys

Retrograde adeno-associated viruses(AAVs)are capable of infecting the axons of projection neurons and serve as a powerful tool for the anatomical and functional characterization of neural networks.However,few retro-grade AAV capsids have been shown to offer access to cor-tical projection neurons across different species and enable the manipulation of neural function in non-human primates(NHPs).Here,we report the development of a novel retro-grade AAV capsid,AAV-DJ8R,which efficiently labeled cortical projection neurons after local administration into the striatum of mice and macaques.In addition,intrastriatally injected AAV-DJ8R mediated opsin expression in the mouse motor cortex and induced robust behavioral alterations.Moreover,AAV-DJ8R markedly increased motor cortical neuron firing upon optogenetic light stimulation after viral delivery into the macaque putamen.These data demonstrate the usefulness of AAV-DJ8R as an efficient retrograde tracer for cortical projection neurons in rodents and NHPs and indicate its suitability for use in conducting functional interrogations.

Optimal Timing of a Commonly-Used Rabies Virus for Neural Recording and Manipulation

Dear Editor,A fundamental goal of modern neuroscience is to dissect the neural circuits in the brain and understand their functions.As a powerful tool for anatomical studies,the genetically modified rabies virus(RV)SADAG(EnvA)has achieved great success in mapping presynaptic inputs to genetically marked neurons[1-3].

Gα_s Relays Sphingosine-1-Phosphate Receptor 1 Signaling to Stabilize Vascular Endothelial-Cadherin at Endothelial Junctions to Control Mouse Embryonic Vascular Integrity

Sphingosine-1-phosphate receptor 1 （S1PR1）, a G protein-coupled recep （GPCR）. controls vasct stability by stabilizing vascular endothelial （VE）-cadherin junctional localization and inhibiting vascular endothelial growth factor receptor 2（VEGFR2） signaling. However, the molecular mechanisms that link S1PR1 signaling to intracellular effectors remain unknown.In this study,we demonstrate that the heterotrimeric G protein subfamily member Gαs, encoded by GNAS,acts as a relay mediator of S1PR1 signaling to control vascular integrity by stabilizing VE-cadherin at endothelial junctions. The endothelial cell -spectific deletion of Gαs in mice causes early embryonic lethality with massive hemorrhage and a disorganized Vaseuiature.The immunostaining results revealed that Gαs deletion remarkably reduces the junctional localization of VE-cadherin, whereas the mull cell coverage of the vessels is not impaired.In addition, we found-that Gαs depletion blocks the S1PR1-activation induced VE-cadherin stabilization at junctons,supporting that Gαs acts downstream of S1PR1 signaling ThuS, our results demonstrate that Gαs is an essential mediator to relay S1PR1 signaling and maintain vascular integrity.