A secretory pathway kinase regulates sarcoplasmic reticulum Ca2+ homeostasis and protects against heart failure

  1. Adam J Pollak
  2. Canzhao Liu
  3. Aparna Gudlur
  4. Joshua E Mayfield
  5. Nancy D Dalton
  6. Yusu Gu
  7. Ju Chen
  8. Joan Heller Brown
  9. Patrick G Hogan
  10. Sandra E Wiley
  11. Kirk L Peterson
  12. Jack E Dixon  Is a corresponding author
  1. University of California, San Diego, United States
  2. La Jolla Institute For Allergy and Immunology, United States

Abstract

Ca2+ signaling is important for many cellular and physiological processes, including cardiac function. Although sarcoplasmic reticulum (SR) proteins involved in Ca2+ signaling have been shown to be phosphorylated, the biochemical and physiological roles of protein phosphorylation within the lumen of the SR remain essentially uncharacterized. Our laboratory recently identified an atypical protein kinase, Fam20C, which is uniquely localized to the secretory pathway lumen. Here we show that Fam20C phosphorylates several SR proteins involved in Ca2+ signaling, including calsequestrin2 and Stim1, whose biochemical activities are dramatically regulated by Fam20C mediated phosphorylation. Notably, phosphorylation of Stim1 by Fam20C enhances Stim1 activation and store-operated Ca2+ entry. Physiologically, mice with Fam20c ablated in cardiomyocytes develop heart failure following either aging or induced pressure overload. We extended these observations to show that non-muscle cells lacking Fam20C display altered ER Ca2+ signaling. Overall, we show that Fam20C plays an overarching role in ER/SR Ca2+ homeostasis and cardiac pathophysiology.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Adam J Pollak

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Canzhao Liu

    Department of Medicine, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Aparna Gudlur

    Division of Signaling and Gene Expression, La Jolla Institute For Allergy and Immunology, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Joshua E Mayfield

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Nancy D Dalton

    Department of Medicine, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Yusu Gu

    Department of Medicine, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Ju Chen

    Department of Medicine, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Joan Heller Brown

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Patrick G Hogan

    Division of Signaling and Gene Expression, La Jolla Institute For Allergy and Immunology, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Sandra E Wiley

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  11. Kirk L Peterson

    Department of Medicine, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  12. Jack E Dixon

    Department of Pharmacology, University of California, San Diego, La Jolla, United States
    For correspondence
    jedixon@ucsd.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8266-5449

Funding

National Institutes of Health (F32HL136122)

  • Adam J Pollak

National Institutes of Health (3T32HL007444-34S1)

  • Adam J Pollak

National Institutes of Health (5T32CA009523-32)

  • Joshua E Mayfield

National Institutes of Health (AI109842)

  • Patrick G Hogan

National Institutes of Health (AI040127)

  • Patrick G Hogan

National Institutes of Health (DK018849-41)

  • Jack E Dixon

National Institutes of Health (DK018024-43)

  • Jack E Dixon

National Institutes of Health (R37HL028143)

  • Joan Heller Brown

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

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols of the University of California at San Diego. The protocol was approved by the Committee on the Ethics of Animal Experiments of the University of California at San Diego (Protocol Number: S03039). All surgery was performed under ketamine and xylazine anesthesia, and every effort was made to minimize suffering.

Reviewing Editor

  1. John Kuriyan, University of California, Berkeley, United States

Publication history

  1. Received: August 23, 2018
  2. Accepted: December 3, 2018
  3. Accepted Manuscript published: December 6, 2018 (version 1)
  4. Version of Record published: December 18, 2018 (version 2)
  5. Version of Record updated: December 24, 2018 (version 3)

Copyright

© 2018, Pollak 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

  • 1,398
    Page views
  • 268
    Downloads
  • 17
    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. Adam J Pollak
  2. Canzhao Liu
  3. Aparna Gudlur
  4. Joshua E Mayfield
  5. Nancy D Dalton
  6. Yusu Gu
  7. Ju Chen
  8. Joan Heller Brown
  9. Patrick G Hogan
  10. Sandra E Wiley
  11. Kirk L Peterson
  12. Jack E Dixon
(2018)
A secretory pathway kinase regulates sarcoplasmic reticulum Ca2+ homeostasis and protects against heart failure
eLife 7:e41378.
https://doi.org/10.7554/eLife.41378

Further reading

    1. Biochemistry and Chemical Biology
    2. Computational and Systems Biology
    Laura M Doherty et al.
    Research Article

    Deubiquitinating enzymes (DUBs), ~100 of which are found in human cells, are proteases that remove ubiquitin conjugates from proteins, thereby regulating protein turnover. They are involved in a wide range of cellular activities and are emerging therapeutic targets for cancer and other diseases. Drugs targeting USP1 and USP30 are in clinical development for cancer and kidney disease respectively. However, the majority of substrates and pathways regulated by DUBs remain unknown, impeding efforts to prioritize specific enzymes for research and drug development. To assemble a knowledgebase of DUB activities, co-dependent genes, and substrates, we combined targeted experiments using CRISPR libraries and inhibitors with systematic mining of functional genomic databases. Analysis of the Dependency Map, Connectivity Map, Cancer Cell Line Encyclopedia, and multiple protein-protein interaction databases yielded specific hypotheses about DUB function, a subset of which were confirmed in follow-on experiments. The data in this paper are browsable online in a newly developed DUB Portal and promise to improve understanding of DUBs as a family as well as the activities of incompletely characterized DUBs (e.g. USPL1 and USP32) and those already targeted with investigational cancer therapeutics (e.g. USP14, UCHL5, and USP7).

    1. Biochemistry and Chemical Biology
    Erich J Goebel et al.
    Research Article

    Activin ligands are formed from two disulfide-linked inhibin β (Inhβ) subunit chains. They exist as homodimeric proteins, as in the case of activin A (ActA; InhβA/InhβA) or activin C (ActC; InhβC/InhβC), or as heterodimers, as with activin AC (ActAC; InhβA:InhβC). While the biological functions of ActA and activin B (ActB) have been well characterized, little is known about the biological functions of ActC or ActAC. One thought is that the InhβC chain functions to interfere with ActA production by forming less active ActAC heterodimers. Here, we assessed and characterized the signaling capacity of ligands containing the InhβC chain. ActC and ActAC activated SMAD2/3-dependent signaling via the type I receptor, activin receptor-like kinase 7 (ALK7). Relative to ActA and ActB, ActC exhibited lower affinity for the cognate activin type II receptors and was resistant to neutralization by the extracellular antagonist, follistatin. In mature murine adipocytes, which exhibit high ALK7 expression, ActC elicited a SMAD2/3 response similar to ActB, which can also signal via ALK7. Collectively, these results establish that ActC and ActAC are active ligands that exhibit a distinct signaling receptor and antagonist profile compared to other activins.