1. Immunology and Inflammation
Download icon

Tight nuclear tethering of cGAS is essential for preventing autoreactivity

  1. Hannah E Volkman
  2. Stephanie Cambier
  3. Elizabeth E Gray
  4. Daniel B Stetson  Is a corresponding author
  1. University of Washington, United States
Research Article
  • Cited 49
  • Views 5,549
  • Annotations
Cite this article as: eLife 2019;8:e47491 doi: 10.7554/eLife.47491
Voice your concerns about research culture and research communication: Have your say in our 7th annual survey.

Abstract

cGAS is an intracellular innate immune sensor that detects double-stranded DNA. The presence of billions of base pairs of genomic DNA in all nucleated cells raises the question of how cGAS is not constitutively activated. A widely accepted explanation for this is the sequestration of cGAS in the cytosol, which is thought to prevent cGAS from accessing nuclear DNA. Here, we demonstrate that endogenous cGAS is predominantly a nuclear protein, regardless of cell cycle phase or cGAS activation status. We show that nuclear cGAS is tethered tightly by a salt-resistant interaction. This tight tethering is independent of the domains required for cGAS activation, and it requires intact nuclear chromatin. We identify the evolutionarily conserved tethering surface on cGAS and we show that mutation of single amino acids within this surface renders cGAS massively and constitutively active against self-DNA. Thus, tight nuclear tethering maintains the resting state of cGAS and prevents autoreactivity.

Data availability

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

Article and author information

Author details

  1. Hannah E Volkman

    Department of Immunology, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Stephanie Cambier

    Department of Immunology, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Elizabeth E Gray

    Department of Immunology, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Daniel B Stetson

    Department of Immunology, University of Washington, Seattle, United States
    For correspondence
    stetson@uw.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5936-1113

Funding

National Institutes of Health (AI084914)

  • Daniel B Stetson

Jane Coffin Childs Memorial Fund for Medical Research

  • Hannah E Volkman

Burroughs Wellcome Fund (1013540)

  • Daniel B Stetson

Howard Hughes Medical Institute (55108572)

  • Daniel B Stetson

Bill and Melinda Gates Foundation (OPP1156262)

  • Daniel B Stetson

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

Reviewing Editor

  1. Tadatsugu Taniguchi, Institute of Industrial Science, The University of Tokyo, Japan

Publication history

  1. Received: December 3, 2018
  2. Accepted: December 5, 2019
  3. Accepted Manuscript published: December 6, 2019 (version 1)
  4. Version of Record published: December 23, 2019 (version 2)

Copyright

© 2019, Volkman 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

  • 5,549
    Page views
  • 976
    Downloads
  • 49
    Citations

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

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)

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

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

Further reading

    1. Immunology and Inflammation
    Emily N Truckenbrod et al.
    Research Article

    Self-specific CD8+ T cells can escape clonal deletion, but the properties and capabilities of such cells in a physiological setting are unclear. We characterized polyclonal CD8+ T cells specific for the melanocyte antigen tyrosinase-related protein 2 (Trp2) in mice expressing or lacking this enzyme (due to deficiency in Dct, which encodes Trp2). Phenotypic and gene expression profiles of pre-immune Trp2/Kb-specific cells were similar; the size of this population was only slightly reduced in wild-type (WT) compared to Dct-deficient (Dct-/-) mice. Despite comparable initial responses to Trp2 immunization, WT Trp2/Kb-specific cells showed blunted expansion and less readily differentiated into a CD25+ proliferative population. Functional self-tolerance clearly emerged when assessing immunopathology: adoptively transferred WT Trp2/Kb-specific cells mediated vitiligo much less efficiently. Hence, CD8+ T cell self-specificity is poorly predicted by precursor frequency, phenotype or even initial responsiveness, while deficient activation-induced CD25 expression and other gene expression characteristics may help to identify functionally tolerant cells.

    1. Immunology and Inflammation
    2. Microbiology and Infectious Disease
    Joseph T Clark et al.
    Research Article

    IL-33 is an alarmin required for resistance to the parasite Toxoplasma gondii, but its role in innate resistance to this organism is unclear. Infection with T. gondii promotes increased stromal cell expression of IL-33 and levels of parasite replication correlate with release of IL-33 in affected tissues. In response to infection, a subset of innate lymphoid cells (ILC) emerges composed of IL-33R+ NK cells and ILC1s. In Rag1-/- mice, where NK cells and ILC1 production of IFN-g mediates innate resistance to T. gondii, the loss of the IL-33R resulted in reduced ILC responses and increased parasite replication. Furthermore, administration of IL-33 to Rag1-/- mice resulted in a marked decrease in parasite burden, increased production of IFN-g and the recruitment and expansion of inflammatory monocytes associated with parasite control. These protective effects of exogenous IL-33 were dependent on endogenous IL-12p40 and the ability of IL-33 to enhance ILC production of IFN-g. These results highlight that IL-33 synergizes with IL-12 to promote ILC-mediated resistance to T. gondii.