The interactome of the copper transporter ATP7A belongs to a network of neurodevelopmental and neurodegeneration factors

  1. Heather S Comstra
  2. Jacob McArthy
  3. Samantha Rudin-Rush
  4. Cortnie Hartwig
  5. Avanti Gokhale
  6. Stephanie A Zlatic
  7. Jessica B Blackburn
  8. Erica Werner
  9. Michael Petris
  10. Priya D'Souza
  11. Parinya Panuwet
  12. Dana Boyd Barr
  13. Vladimir Lupashin
  14. Alysia Vrailas-Mortimer  Is a corresponding author
  15. Victor Faundez  Is a corresponding author
  1. Emory University, United States
  2. Illinois State University, United States
  3. Agnes Scott College, United States
  4. University of Arkansas for Medical Sciences, United States
  5. University of Missouri, United States

Abstract

Genetic and environmental factors, such as metals, interact to determine neurological traits. We reasoned that interactomes of molecules handling metals in neurons should include novel metal homeostasis pathways. We focused on copper and its transporter ATP7A because ATP7A null mutations cause neurodegeneration. We performed ATP7A immunoaffinity chromatography and identified 541 proteins co-isolating with ATP7A. The ATP7A interactome concentrated gene products implicated in neurodegeneration and neurodevelopmental disorders, including subunits of the Golgi-localized conserved oligomeric Golgi (COG) complex. COG null cells possess altered content and subcellular localization of ATP7A and CTR1 (SLC31A1), the transporter required for copper uptake, as well as decreased total cellular copper, and impaired copper-dependent metabolic responses. Changes in the expression of ATP7A and COG subunits in Drosophila neurons altered synapse development in larvae and copper-induced mortality of adult flies. We conclude that the ATP7A interactome encompasses a novel COG-dependent mechanism to specify neuronal development and survival.

Article and author information

Author details

  1. Heather S Comstra

    Department of Cell Biology, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Jacob McArthy

    School of Biological Sciences, Illinois State University, Normal, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Samantha Rudin-Rush

    Department of Chemistry, Agnes Scott College, Decatur, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Cortnie Hartwig

    Department of Chemistry, Agnes Scott College, Decatur, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Avanti Gokhale

    Department of Cell Biology, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Stephanie A Zlatic

    Department of Cell Biology, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Jessica B Blackburn

    Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Erica Werner

    Department of Biochemistry, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Michael Petris

    Department of Biochemistry, University of Missouri, Columbia, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Priya D'Souza

    Department of Rollins School of Public Health, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  11. Parinya Panuwet

    Department of Rollins School of Public Health, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  12. Dana Boyd Barr

    Department of Rollins School of Public Health, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  13. Vladimir Lupashin

    Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2350-1962
  14. Alysia Vrailas-Mortimer

    School of Biological Sciences, Illinois State University, Normal, United States
    For correspondence
    avraila@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
  15. Victor Faundez

    Department of Cell Biology, Emory University, Atlanta, United States
    For correspondence
    vfaunde@emory.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2114-5271

Funding

National Institute of Neurological Disorders and Stroke (NS088503)

  • Victor Faundez

National Institute of Diabetes and Digestive and Kidney Diseases (DK093386)

  • Michael Petris

National Institute of General Medical Sciences (GM083144)

  • Vladimir Lupashin

National Institute of Environmental Health Sciences (P30 ES019776)

  • Dana Boyd Barr

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

Reviewing Editor

  1. Andrew B West, University of Alabama at Birmingham, United States

Publication history

  1. Received: December 28, 2016
  2. Accepted: March 28, 2017
  3. Accepted Manuscript published: March 29, 2017 (version 1)
  4. Accepted Manuscript updated: April 5, 2017 (version 2)
  5. Version of Record published: April 21, 2017 (version 3)

Copyright

© 2017, Comstra 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.

Metrics

  • 2,747
    Page views
  • 581
    Downloads
  • 42
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Heather S Comstra
  2. Jacob McArthy
  3. Samantha Rudin-Rush
  4. Cortnie Hartwig
  5. Avanti Gokhale
  6. Stephanie A Zlatic
  7. Jessica B Blackburn
  8. Erica Werner
  9. Michael Petris
  10. Priya D'Souza
  11. Parinya Panuwet
  12. Dana Boyd Barr
  13. Vladimir Lupashin
  14. Alysia Vrailas-Mortimer
  15. Victor Faundez
(2017)
The interactome of the copper transporter ATP7A belongs to a network of neurodevelopmental and neurodegeneration factors
eLife 6:e24722.
https://doi.org/10.7554/eLife.24722
  1. Further reading

Further reading

    1. Biochemistry and Chemical Biology
    2. Cell Biology
    Tolulope Sokoya, Jan Parolek ... Joost CM Holthuis
    Research Article Updated

    Sphingomyelin is a dominant sphingolipid in mammalian cells. Its production in the trans-Golgi traps cholesterol synthesized in the ER to promote formation of a sphingomyelin/sterol gradient along the secretory pathway. This gradient marks a fundamental transition in physical membrane properties that help specify organelle identify and function. We previously identified mutations in sphingomyelin synthase SMS2 that cause osteoporosis and skeletal dysplasia. Here, we show that SMS2 variants linked to the most severe bone phenotypes retain full enzymatic activity but fail to leave the ER owing to a defective autonomous ER export signal. Cells harboring pathogenic SMS2 variants accumulate sphingomyelin in the ER and display a disrupted transbilayer sphingomyelin asymmetry. These aberrant sphingomyelin distributions also occur in patient-derived fibroblasts and are accompanied by imbalances in cholesterol organization, glycerophospholipid profiles, and lipid order in the secretory pathway. We postulate that pathogenic SMS2 variants undermine the capacity of osteogenic cells to uphold nonrandom lipid distributions that are critical for their bone forming activity.

    1. Cell Biology
    2. Structural Biology and Molecular Biophysics
    Thomas GW Graham, John Joseph Ferrie ... Xavier Darzacq
    Research Article Updated

    Single-molecule imaging provides a powerful way to study biochemical processes in live cells, yet it remains challenging to track single molecules while simultaneously detecting their interactions. Here, we describe a novel property of rhodamine dyes, proximity-assisted photoactivation (PAPA), in which one fluorophore (the ‘sender’) can reactivate a second fluorophore (the ‘receiver’) from a dark state. PAPA requires proximity between the two fluorophores, yet it operates at a longer average intermolecular distance than Förster resonance energy transfer (FRET). We show that PAPA can be used in live cells both to detect protein–protein interactions and to highlight a subpopulation of labeled protein complexes in which two different labels are in proximity. In proof-of-concept experiments, PAPA detected the expected correlation between androgen receptor self-association and chromatin binding at the single-cell level. These results establish a new way in which a photophysical property of fluorophores can be harnessed to study molecular interactions in single-molecule imaging of live cells.