1. Neuroscience
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Dendritic coincidence detection in Purkinje neurons of awake mice

  1. Christopher J Roome  Is a corresponding author
  2. Bernd Kuhn  Is a corresponding author
  1. OIST Graduate University, Japan
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Cite this article as: eLife 2020;9:e59619 doi: 10.7554/eLife.59619

Abstract

Dendritic coincidence detection is thought fundamental to neuronal processing yet remains largely unexplored in awake animals. Specifically, the underlying dendritic voltage-calcium relationship has not been directly addressed. Here, using simultaneous voltage and calcium two-photon imaging of Purkinje neuron spiny dendrites, we show how coincident synaptic inputs and resulting dendritic spikes modulate dendritic calcium signaling during sensory stimulation in awake mice. Sensory stimulation increased the rate of post-synaptic potentials and dendritic calcium spikes evoked by climbing fiber and parallel fiber synaptic input. These inputs are integrated in a time-dependent and non-linear fashion to enhance the sensory evoked dendritic calcium signal. Intrinsic supralinear dendritic mechanisms, including voltage-gated calcium channels and metabotropic glutamate receptors, are recruited cooperatively to expand the dynamic range of sensory evoked dendritic calcium signals. This establishes how dendrites can use multiple interplaying mechanisms to perform coincidence detection, as a fundamental and ongoing feature of dendritic integration in behaving animals.

Data availability

Matlab codes are available at: https://github.com/cjroome/Roome_and_Kuhn_2020Data is available at: https://doi.org/10.5061/dryad.6hdr7sqzt

The following data sets were generated

Article and author information

Author details

  1. Christopher J Roome

    Optical Neuroimaging, OIST Graduate University, Onna, Japan
    For correspondence
    christopher.roome@oist.jp
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8936-668X
  2. Bernd Kuhn

    Optical Neuroimaging, OIST Graduate University, Onna, Japan
    For correspondence
    bkuhn@oist.jp
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6852-2433

Funding

Okinawa Institute of Science and Technology Graduate University

  • Christopher J Roome
  • Bernd Kuhn

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All animal procedures were conducted in accordance with guidelines of the Okinawa Institute of Science and Technology Institutional Animal Care and Use Committee in an Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC International)-accredited facility, under protocol numbers: 2016-170, 2019-279.

Reviewing Editor

  1. Megan R Carey, Champalimaud Foundation, Portugal

Publication history

  1. Received: June 3, 2020
  2. Accepted: December 18, 2020
  3. Accepted Manuscript published: December 21, 2020 (version 1)
  4. Version of Record published: December 29, 2020 (version 2)

Copyright

© 2020, Roome & Kuhn

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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