title: Local retinal circuits of melanopsin-containing ganglion cells identified by transsynaptic viral tracing.
abstract: Intrinsically photosensitive melanopsin-containing retinal ganglion cells (ipRGCs) control important physiological processes, including the circadian rhythm, the pupillary reflex, and the suppression of locomotor behavior (reviewed in [1]). ipRGCs are also activated by classical photoreceptors, the rods and cones, through local retinal circuits [2, 3]. ipRGCs can be transsynaptically labeled through the pupillary-reflex circuit with the derivatives of the Bartha strain of the alphaherpesvirus pseudorabies virus(PRV) [4, 5] that express GFP [6-12]. Bartha-strain derivatives spread only in the retrograde direction [13]. There is evidence that infected cells function normally for a while during GFP expression [7]. Here we combine transsynaptic PRV labeling, two-photon laser microscopy, and electrophysiological techniques to trace the local circuit of different ipRGC subtypes in the mouse retina and record light-evoked activity from the transsynaptically labeled ganglion cells. First, we show that ipRGCs are connected by monostratified amacrine cells that provide strong inhibition from classical-photoreceptor-driven circuits. Second, we show evidence that dopaminergic interplexiform cells are synaptically connected to ipRGCs. The latter finding provides a circuitry link between light-dark adaptation and ipRGC function.
authors.affiliation: Neural Circuit Laboratories, Friedrich Miescher Institute, Maulbeerstrasse 66, Basel 4058, Switzerland.
authors.forename: Tim James
authors.initials: TJ
authors.lastname: Viney
authors.forename: Kamill
authors.initials: K
authors.lastname: Balint
authors.forename: Daniel
authors.initials: D
authors.lastname: Hillier
authors.forename: Sandra
authors.initials: S
authors.lastname: Siegert
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Boldogkoi
authors.forename: Lynn W
authors.initials: LW
authors.lastname: Enquist
authors.forename: Markus
authors.initials: M
authors.lastname: Meister
authors.forename: Constance L
authors.initials: CL
authors.lastname: Cepko
authors.forename: Botond
authors.initials: B
authors.lastname: Roska
mesh_terms: D025042:Amacrine Cells / Q000502:physiology / Q000821:virology; D000818:Animals; D049452:Green Fluorescent Proteins / Q000032:analysis; D011558:Herpesvirus 1, Suid / Q000235:genetics / Q000378:metabolism; D051379:Mice; D012165:Retinal Ganglion Cells / Q000502:physiology* / Q000528:radiation effects / Q000821:virology; D017299:Rod Opsins / Q000378:metabolism*; D009435:Synaptic Transmission; D014795:Visual Pathways / Q000502:physiology*; D000099210:Melanopsin
chemical_list: D049452:Green Fluorescent Proteins; D017299:Rod Opsins; D000099210:Melanopsin