GFP fluorescence reports Period 1 circadian gene regulation in the mammalian biological clock

Neuroreport. 2000 May 15;11(7):1479-82.


Endogenous cyclic activation of a specific set of genes, including Period 1 (Per1), drive circadian rhythms in the suprachiasmatic nucleus (SCN), a biological clock nucleus of the brain. We have produced transgenic mice in which a degradable form of recombinant jellyfish green fluorescent protein (GFP) is driven by the mouse Period 1 (mPer1) gene promoter. GFP protein is expressed in the circadian neural structures of the retina and SCN. Fluorescent signals are resolved at the level of individual neurons. mPer1-driven GFP fluorescence intensity reports light-induction and circadian rhythmicity in SCN neurons. This circadian reporter transgene captures the gene expression dynamics of living biological clock neurons and ensembles, providing a novel view of this brain function.

Publication types

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

MeSH terms

  • Animals
  • Biological Clocks / physiology*
  • Cell Cycle Proteins
  • Female
  • Gene Expression Regulation / physiology
  • Genes, Reporter
  • Green Fluorescent Proteins
  • In Situ Hybridization
  • Indicators and Reagents / metabolism*
  • Luminescent Proteins / genetics*
  • Male
  • Mice
  • Mice, Inbred C3H
  • Mice, Transgenic
  • Nuclear Proteins / genetics*
  • Period Circadian Proteins
  • RNA, Messenger / analysis
  • Suprachiasmatic Nucleus / physiology*
  • Transgenes / physiology


  • Cell Cycle Proteins
  • Indicators and Reagents
  • Luminescent Proteins
  • Nuclear Proteins
  • Per1 protein, mouse
  • Period Circadian Proteins
  • RNA, Messenger
  • Green Fluorescent Proteins