Loss of Drosophila melanogaster TRPA1 Function Affects "Siesta" Behavior but Not Synchronization to Temperature Cycles

J Biol Rhythms. 2015 Dec;30(6):492-505. doi: 10.1177/0748730415605633. Epub 2015 Oct 12.

Abstract

To maintain synchrony with the environment, circadian clocks use a wide range of cycling sensory cues that provide input to the clock (zeitgebers), including environmental temperature cycles (TCs). There is some knowledge about which clock neuronal groups are important for temperature synchronization, but we currently lack knowledge on the temperature receptors and their signaling pathways that feed temperature information to the (neuronal) clock. Since TRPA1 is a well-known thermosensor that functions in a range of temperature-related behaviors, and it is potentially expressed in clock neurons, we set out to test the putative role of TRPA1 in temperature synchronization of the circadian clock. We found that flies lacking TRPA1 are still able to synchronize their behavioral activity to TCs comparable to wild-type flies, both in 16°C : 25°C and 20°C : 29°C TCs. In addition, we found that flies lacking TRPA1 show higher activity levels during the middle of the warm phase of 20°C : 29°C TCs, and we show that this TRPA1-mediated repression of locomotor activity during the "siesta" is caused by a lack of sleep. Based on these data, we conclude that the TRPA1 channel is not required for temperature synchronization in this broad temperature range but instead is required to repress activity during the warm part of the day.

Keywords: Drosophila melanogaster; TRPA1; circadian clocks; sleep; temperature entrainment; thermo TRP channels.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Circadian Clocks / genetics
  • Circadian Clocks / physiology
  • Circadian Rhythm
  • Cues
  • Drosophila Proteins / deficiency
  • Drosophila Proteins / genetics*
  • Drosophila Proteins / physiology*
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / physiology*
  • Ion Channels
  • Motor Activity
  • Mutation
  • Neurons / physiology
  • Sleep / genetics*
  • Sleep / physiology
  • TRPA1 Cation Channel
  • TRPC Cation Channels / deficiency
  • TRPC Cation Channels / genetics*
  • TRPC Cation Channels / physiology*
  • Temperature*
  • Transcription Factors / metabolism

Substances

  • Drosophila Proteins
  • Ion Channels
  • TRPA1 Cation Channel
  • TRPC Cation Channels
  • Transcription Factors
  • TrpA1 protein, Drosophila