Melanopsin mediates retrograde visual signaling in the retina

PLoS One. 2012;7(8):e42647. doi: 10.1371/journal.pone.0042647. Epub 2012 Aug 3.


The canonical flow of visual signals proceeds from outer to inner retina (photoreceptors → bipolar cells → ganglion cells). However, melanopsin-expressing ganglion cells are photosensitive and functional sustained light signaling to retinal dopaminergic interneurons persists in the absence of rods and cones. Here we show that the sustained-type light response of retinal dopamine neurons requires melanopsin and that the response is mediated by AMPA-type glutamate receptors, defining a retrograde retinal visual signaling pathway that fully reverses the usual flow of light signals in retinal circuits.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dopaminergic Neurons / metabolism
  • Dopaminergic Neurons / radiation effects
  • Light
  • Mice
  • Mice, Transgenic
  • Receptors, AMPA / metabolism
  • Retina / metabolism*
  • Retina / radiation effects
  • Rod Opsins / metabolism*
  • Signal Transduction* / radiation effects
  • Synaptic Transmission / radiation effects
  • Visual Pathways* / radiation effects


  • Receptors, AMPA
  • Rod Opsins
  • melanopsin