Neuronal processing of noxious thermal stimuli mediated by dendritic Ca2+ influx in Drosophila somatosensory neurons

  1. Shin-Ichiro Terada
  2. Daisuke Matsubara
  3. Koun Onodera
  4. Masanori Matsuzaki
  5. Tadashi Uemura
  6. Tadao Usui  Is a corresponding author
  1. Kyoto University, Japan
  2. National Institute for Basic Biology, Japan

Abstract

Adequate responses to noxious stimuli causing tissue damages are essential for organismal survival. Class IV neurons in Drosophila larvae are polymodal nociceptors responsible for thermal, mechanical, and light sensation. Importantly, activation of Class IV provoked distinct avoidance behaviors, depending on the inputs. We found that noxious thermal stimuli, but not blue light stimulation, caused a unique pattern of Class IV, which were composed of pauses after high frequency spike trains and a large Ca2+ rise in the dendrite (the Ca2+ transient). Both of these responses depended on two TRPA channels and the L-type voltage-gated calcium channel (L-VGCC), showing that the thermosensation provokes Ca2+ influx. The precipitous fluctuation of firing rate in Class IV neurons enhanced the robust heat avoidance. We hypothesize that the Ca2+ influx can be a key signal encoding a specific modality.

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Author details

  1. Shin-Ichiro Terada

    Graduate School of Biostudies, Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
  2. Daisuke Matsubara

    Graduate School of Biostudies, Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
  3. Koun Onodera

    Graduate School of Biostudies, Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
  4. Masanori Matsuzaki

    Division of Brain Circuits, National Institute for Basic Biology, Okazaki, Japan
    Competing interests
    The authors declare that no competing interests exist.
  5. Tadashi Uemura

    Graduate School of Biostudies, Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
  6. Tadao Usui

    Graduate School of Biostudies, Kyoto University, Kyoto, Japan
    For correspondence
    tadao.usui@gmail.com
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Leslie C Griffith, Brandeis University, United States

Version history

  1. Received: November 11, 2015
  2. Accepted: February 13, 2016
  3. Accepted Manuscript published: February 15, 2016 (version 1)
  4. Version of Record published: February 29, 2016 (version 2)

Copyright

© 2016, Terada et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Shin-Ichiro Terada
  2. Daisuke Matsubara
  3. Koun Onodera
  4. Masanori Matsuzaki
  5. Tadashi Uemura
  6. Tadao Usui
(2016)
Neuronal processing of noxious thermal stimuli mediated by dendritic Ca2+ influx in Drosophila somatosensory neurons
eLife 5:e12959.
https://doi.org/10.7554/eLife.12959

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https://doi.org/10.7554/eLife.12959

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