A role for the Drosophila fragile X-related gene in circadian output

Curr Biol. 2002 Aug 6;12(15):1331-5. doi: 10.1016/s0960-9822(02)01036-9.


Mutations that abolish expression of an X-linked gene, FMR1, result in the pathogenesis of fragile X syndrome, the most common form of inherited mental retardation. To understand the normal function of the FMR1 protein, we have produced fly strains bearing deletions in a Drosophila homolog of FMR1 (dfmr1). Since fragile X patients show a number of abnormal behaviors including sleep problems, we investigated whether a loss-of-function mutation of dfmr1 affect circadian behavior. Here we show that under constant darkness (DD), a lack of dfmr1 expression causes arrhythmic locomotor activity, but in light:dark cycles, their behavioral rhythms appear normal. In addition, the clock-controlled eclosion rhythm is normal in DFMR1-deficient flies. These results suggest that DFMR1 plays a critical role in the circadian output pathway regulating locomotor activity in Drosophila.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Circadian Rhythm / genetics*
  • Drosophila / genetics
  • Drosophila / physiology*
  • Drosophila Proteins*
  • Fragile X Mental Retardation Protein
  • Fragile X Syndrome / genetics*
  • Gene Deletion
  • Humans
  • Models, Animal
  • RNA-Binding Proteins / genetics*
  • Time Factors
  • X Chromosome*


  • Drosophila Proteins
  • FMR1 protein, Drosophila
  • RNA-Binding Proteins
  • Fragile X Mental Retardation Protein