Cellular location and circadian rhythm of expression of the biological clock gene Period 1 in the mouse retina

J Neurosci. 2003 Aug 20;23(20):7670-6. doi: 10.1523/JNEUROSCI.23-20-07670.2003.


The cellular location and rhythmic expression of Period 1 (Per1) circadian clock gene were examined in the retina of a Per1::GFP transgenic mouse. Mouse Per1 (mPer1) RNA was localized to inner nuclear and ganglion cell layers but was absent in the outer nuclear (photoreceptor) layer. Green fluorescent protein (GFP), which was shown to colocalize with PER1 protein, was found in a few subtypes of amacrine neuron, including those containing tyrosine hydroxylase, calbindin, and calretinin, but not in cholinergic amacrine cells. A small subset of ganglion cells also contained GFP immunoreactivity (GFP-IR), but the melanopsin-containing subtype, which projects to the suprachiasmatic nuclei (SCN), lacked GFP-IR. Although the intensity of GFP-IR varied among the populations of amacrine cells at each time point that was examined, both diurnal and circadian rhythms were found for the fraction of neurons showing strong GFP-IR, with peak expression between Zeitgeber/circadian (ZT/CT) times 10 and 14. In SCNs that were examined in the same mice used for the retinal measures, the peak in GFP-IR also occurred at approximately ZT/CT 10. Our results are the first to demonstrate a circadian rhythm of a biological clock component in identified neurons of a mammalian retina.

Publication types

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

MeSH terms

  • Amacrine Cells / chemistry
  • Animals
  • Cell Cycle Proteins
  • Circadian Rhythm*
  • Green Fluorescent Proteins
  • Immunohistochemistry
  • In Situ Hybridization
  • Luminescent Proteins / analysis
  • Luminescent Proteins / genetics
  • Luminescent Proteins / immunology
  • Mice
  • Mice, Transgenic
  • Nuclear Proteins / analysis*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Period Circadian Proteins
  • RNA, Messenger / analysis
  • Recombinant Fusion Proteins / analysis
  • Retina / chemistry*
  • Retina / metabolism*
  • Retinal Ganglion Cells / chemistry
  • Suprachiasmatic Nucleus / chemistry


  • Cell Cycle Proteins
  • Luminescent Proteins
  • Nuclear Proteins
  • Per1 protein, mouse
  • Period Circadian Proteins
  • RNA, Messenger
  • Recombinant Fusion Proteins
  • Green Fluorescent Proteins