Local retinal circuits of melanopsin-containing ganglion cells identified by transsynaptic viral tracing

Curr Biol. 2007 Jun 5;17(11):981-8. doi: 10.1016/j.cub.2007.04.058. Epub 2007 May 24.


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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amacrine Cells / physiology
  • Amacrine Cells / virology
  • Animals
  • Green Fluorescent Proteins / analysis
  • Herpesvirus 1, Suid / genetics
  • Herpesvirus 1, Suid / metabolism
  • Mice
  • Retinal Ganglion Cells / physiology*
  • Retinal Ganglion Cells / radiation effects
  • Retinal Ganglion Cells / virology
  • Rod Opsins / metabolism*
  • Synaptic Transmission
  • Visual Pathways / physiology*


  • Rod Opsins
  • melanopsin
  • Green Fluorescent Proteins