Cellular and Molecular Life Sciences

, Volume 67, Issue 1, pp 99–111

Melanopsin and inner retinal photoreception


DOI: 10.1007/s00018-009-0155-7

Cite this article as:
Bailes, H.J. & Lucas, R.J. Cell. Mol. Life Sci. (2010) 67: 99. doi:10.1007/s00018-009-0155-7


Over the last ten years there has been growing acceptance that retinal photoreception among mammals extends beyond rods and cones to include a small number of intrinsically photosensitive retinal ganglion cells (ipRGCs). These ipRGCs are capable of responding to light in the absence of rod/cone input thanks to expression of an opsin photopigment called melanopsin. They are specialised for measuring ambient levels of light (irradiance) for a wide variety of so-called non-image-forming light responses. These include synchronisation of circadian clocks to light:dark cycles and the regulation of pupil size, sleep propensity and pineal melatonin production. Here, we provide a review of some of the landmark discoveries in this fast developing field, paying particular emphasis to recent findings and key areas for future investigation.


RetinaGanglion cellsPhotoreceptionCircadian rhythmsOpsinPhotosensitivity

Copyright information

© Birkhäuser Verlag, Basel/Switzerland 2009

Authors and Affiliations

  1. 1.Faculty of Life SciencesThe University of ManchesterManchesterUK