Transgene expression in target-defined neuron populations mediated by retrograde infection with adeno-associated viral vectors.
Tools enabling the manipulation of well defined neuronal subpopulations are critical for probing complex neuronal networks. Cre recombinase (Cre) mouse driver lines in combination with the Cre-dependent expression of proteins using viral vectors--in particular, recombinant adeno-associated viral vectors (rAAVs)--have emerged as a widely used platform for achieving transgene expression in specified neural populations. However, the ability of rAAVs to further specify neuronal subsets on the basis of their anatomical connectivity has been reported as limited or inconsistent. Here, we systematically tested a variety of widely used neurotropic rAAVs for their ability to mediate retrograde gene transduction in the mouse brain. We tested pseudotyped rAAVs of several common serotypes (rAAV 2/1, 2/5, and 2/9) as well as constructs both with and without Cre-dependent expression switches. Many of the rAAVs tested--in particular, though not exclusively, Cre-dependent vectors--showed a robust capacity for retrograde infection and transgene expression. Retrograde expression was successful over distances as large as 6 mm and in multiple neuron types, including olfactory projection neurons, neocortical pyramidal cells projecting to distinct targets, and corticofugal and modulatory projection neurons. Retrograde infection using transgenes such as ChR2 allowed for optical control or optically assisted electrophysiological identification of neurons defined genetically as well as by their projection target. These results establish a widely accessible tool for achieving combinatorial specificity and stable, long-term transgene expression to isolate precisely defined neuron populations in the intact animal.
Brain Institute and Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, Utah 84112.
Markus
M
Rothermel
Daniela
D
Brunert
Christine
C
Zabawa
Marta
M
Díaz-Quesada
Matt
M
Wachowiak
D000200:Action Potentials / Q000235:genetics; D000818:Animals; D000075402:Channelrhodopsins; D002766:Cholecystokinin / Q000235:genetics / Q000378:metabolism; D000229:Dependovirus / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics / Q000502:physiology*; D005822:Genetic Vectors / Q000502:physiology*; D005968:Glutamate Decarboxylase / Q000235:genetics; D019426:Integrases; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009434:Neural Pathways / Q000378:metabolism; D009474:Neurons / Q000145:classification / Q000378:metabolism*; D009833:Olfactory Pathways / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D062308:Optogenetics; D018408:Patch-Clamp Techniques; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics; D014161:Transduction, Genetic
D000075402:Channelrhodopsins; D008164:Luminescent Proteins; D050486:Serotonin Plasma Membrane Transport Proteins; C493231:Slc6a4 protein, mouse; D002766:Cholecystokinin; C045073:Cre recombinase; D019426:Integrases; D005968:Glutamate Decarboxylase; C401141:glutamate decarboxylase 2