Sexual interactions influence the molecular oscillations in DN1 pacemaker neurons in Drosophila melanogaster

PLoS One. 2013 Dec 18;8(12):e84495. doi: 10.1371/journal.pone.0084495. eCollection 2013.


Circadian rhythms can synchronize to environmental time cues, such as light, temperature, humidity, and food availability. Previous studies have suggested that these rhythms can also be entrained by social interactions. Here, we used Drosophila melanogaster as a model to study the influence of socio-sexual interactions on the circadian clock in behavior and pacemaker neurons. If two flies of opposite sex were paired and kept in a small space, the daily activity patterns of the two flies were clearly different from the sum of the activity of single male and female flies. Compared with single flies, paired flies were more active in the night and morning, were more active during females' active phase, and were less active during males' active phase. These behavioral phenotypes are related to courtship behavior, but not to the circadian clock. Nevertheless, in male-female pairs of flies with clocks at different speeds (wild-type and per (S) flies), clock protein cycling in the DN1 pacemaker neurons in the male brain were slightly influenced by their partners. These results suggest that sexual interactions between male-female couples can serve as a weak zeitgeber for the DN1 pacemaker neurons, but the effect is not sufficient to alter rhythms of behavioral activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / cytology
  • Brain / physiology
  • Circadian Clocks*
  • Drosophila Proteins / genetics
  • Drosophila melanogaster / cytology*
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / physiology*
  • Female
  • Male
  • Mutation
  • Nerve Tissue Proteins / genetics
  • Neurons / cytology*
  • Sexual Behavior, Animal / physiology*
  • Transcription Factors / genetics


  • Drosophila Proteins
  • Nerve Tissue Proteins
  • Transcription Factors
  • fru protein, Drosophila

Grants and funding

This work was supported by Grant for Basic Science Research Projects from the Sumitomo Foundation, Inamori Foundation, Ryobi Teien Memory Foundation and research grants from Grants-in-Aid for Scientific Research (KAKENHI 23870021 and 25840121 to TY, and KAKENHI 19657027 and 23657056 to KT). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.