Magnesium efflux from Drosophila Kenyon Cells is critical for normal and diet-enhanced long-term memory

  1. Yanying Wu
  2. Yosuke Funato
  3. Eleonora Meschi
  4. Kristijan Jovanoski
  5. Hiroaki Miki
  6. Scott Waddell  Is a corresponding author
  1. University of Oxford, United Kingdom
  2. Osaka University, Japan

Abstract

Dietary magnesium (Mg2+) supplementation can enhance memory in young and aged rats. Memory-enhancing capacity was largely ascribed to increases in hippocampal synaptic density and elevated expression of the NR2B subunit of the NMDA-type glutamate receptor. Here we show that Mg2+ feeding also enhances long-term memory in Drosophila. Normal and Mg2+ enhanced fly memory appears independent of NMDA receptors in the mushroom body and instead requires expression of a conserved CNNM-type Mg2+-efflux transporter encoded by the unextended (uex) gene. UEX contains a putative cyclic nucleotide-binding homology domain and its mutation separates a vital role for uex from a function in memory. Moreover, UEX localization in mushroom body Kenyon Cells is altered in memory defective flies harboring mutations in cAMP-related genes. Functional imaging suggests that UEX-dependent efflux is required for slow rhythmic maintenance of Kenyon Cell Mg2+. We propose that regulated neuronal Mg2+ efflux is critical for normal and Mg2+ enhanced memory.

Data availability

Behaviour data from T-maza assays deposited in Dryad Digital Repository (doi:10.5061/dryad.q2bvq83hs). All other data generated or analysed during this study are included in the manuscript and supporting files.

The following data sets were generated

Article and author information

Author details

  1. Yanying Wu

    Centre for Neural Circuits & Behaviour, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Yosuke Funato

    Department of Cellular Regulation, Osaka University, Osaka, Japan
    Competing interests
    The authors declare that no competing interests exist.
  3. Eleonora Meschi

    Centre for Neural Circuits & Behaviour, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2401-7969
  4. Kristijan Jovanoski

    Centre for Neural Circuits & Behaviour, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Hiroaki Miki

    Department of Cellular Regulation, Osaka University, Osaka, Japan
    Competing interests
    The authors declare that no competing interests exist.
  6. Scott Waddell

    Centre for Neural Circuits & Behaviour, University of Oxford, Oxford, United Kingdom
    For correspondence
    scott.waddell@cncb.ox.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4503-6229

Funding

Wellcome (200846/Z/16/Z)

  • Scott Waddell

European Commission (789274)

  • Scott Waddell

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

Copyright

© 2020, Wu 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. Yanying Wu
  2. Yosuke Funato
  3. Eleonora Meschi
  4. Kristijan Jovanoski
  5. Hiroaki Miki
  6. Scott Waddell
(2020)
Magnesium efflux from Drosophila Kenyon Cells is critical for normal and diet-enhanced long-term memory
eLife 9:e61339.
https://doi.org/10.7554/eLife.61339

Share this article

https://doi.org/10.7554/eLife.61339

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