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

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.

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  1. Hannah E Volkman
  2. Stephanie Cambier
  3. Elizabeth E Gray
  4. Daniel B Stetson
(2019)
Tight nuclear tethering of cGAS is essential for preventing autoreactivity
eLife 8:e47491.
https://doi.org/10.7554/eLife.47491

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