Circadian and Genetic Modulation of Visually-Guided Navigation in Drosophila Larvae

Sci Rep. 2020 Feb 17;10(1):2752. doi: 10.1038/s41598-020-59614-y.

Abstract

Organisms possess an endogenous molecular clock which enables them to adapt to environmental rhythms and to synchronize their metabolism and behavior accordingly. Circadian rhythms govern daily oscillations in numerous physiological processes, and the underlying molecular components have been extensively described from fruit flies to mammals. Drosophila larvae have relatively simple nervous system compared to their adult counterparts, yet they both share a homologous molecular clock with mammals, governed by interlocking transcriptional feedback loops with highly conserved constituents. Larvae exhibit a robust light avoidance behavior, presumably enabling them to avoid predators and desiccation, and DNA-damage by exposure to ultraviolet light, hence are crucial for survival. Circadian rhythm has been shown to alter light-dark preference, however it remains unclear how distinct behavioral strategies are modulated by circadian time. To address this question, we investigate the larval visual navigation at different time-points of the day employing a computer-based tracking system, which allows detailed evaluation of distinct navigation strategies. Our results show that due to circadian modulation specific to light information processing, larvae avoid light most efficiently at dawn, and a functioning clock mechanism at both molecular and neuro-signaling level is necessary to conduct this modulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • CLOCK Proteins / genetics*
  • CLOCK Proteins / metabolism
  • Circadian Clocks / physiology
  • Circadian Rhythm / physiology*
  • Drosophila Proteins / genetics*
  • Drosophila Proteins / metabolism
  • Drosophila melanogaster / genetics*
  • Drosophila melanogaster / growth & development
  • Drosophila melanogaster / metabolism
  • Gene Expression Regulation, Developmental
  • Genotype
  • Larva / genetics*
  • Larva / growth & development
  • Larva / metabolism
  • Neuropeptides / genetics*
  • Neuropeptides / metabolism
  • Period Circadian Proteins / genetics*
  • Period Circadian Proteins / metabolism
  • Photic Stimulation
  • Spatial Navigation
  • Vision, Ocular / physiology

Substances

  • Clk protein, Drosophila
  • Drosophila Proteins
  • Neuropeptides
  • PER protein, Drosophila
  • Period Circadian Proteins
  • pdf protein, Drosophila
  • CLOCK Proteins