PKCθ links proximal T cell and Notch signaling through localized regulation of the actin cytoskeleton

Abstract

Notch is a critical regulator of T cell differentiation and is activated through proteolytic cleavage in response to ligand engagement. Using murine myelin-reactive CD4 T cells we demonstrate that proximal T cell signaling modulates Notch activation by a spatiotemporally constrained mechanism. The protein kinase PKCθ is a critical mediator of signaling by the T cell antigen receptor and the principal costimulatory receptor CD28. PKCθ selectively inactivates the negative regulator of F-actin generation, Coronin 1A, at the center of the T cell interface with the antigen presenting cell (APC). This allows for effective generation of the large actin-based lamellum required for recruitment of the Notch-processing membrane metalloproteinase ADAM10. Such enhancement of Notch activation is critical for efficient T cell proliferation and Th17 differentiation. We reveal a novel mechanism that, through modulation of the cytoskeleton, controls Notch activation at the T cell:APC interface thereby linking T cell receptor and Notch signaling pathways.

Article and author information

Author details

  1. Graham J Britton

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Rachel Ambler

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6647-4116
  3. Danielle J Clark

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Elaine V Hill

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Helen M Tunbridge

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Kerrie E McNally

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Bronwen R Burton

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Philomena Butterweck

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  9. Catherine Sabatos-Peyton

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  10. Lea A Hampton-O'Neil

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9665-170X
  11. Paul Verkade

    School of Biochemistry, University of Bristol, Bristol, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  12. Christoph Wülfing

    School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
    For correspondence
    Christoph.Wuelfing@bristol.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
  13. David Cameron Wraith

    Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
    For correspondence
    d.wraith@bham.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2147-5614

Funding

European Research Council (PCIG-GA-2012-321554)

  • Christoph Wuelfing

Multiple Sclerosis Society (900/08)

  • Catherine Sabatos-Peyton

Wellcome Trust (102387/Z/13/Z)

  • Rachel Ambler
  • Helen M Tunbridge
  • Kerrie E McNally
  • Lea A Hampton-O'Neil

Wellcome Trust (091074/Z/09/Z)

  • Elaine V Hill
  • David Cameron Wraith

University of Bristol (PhD studentship)

  • Danielle J Clark

Wellcome Trust (086779/Z/08/A)

  • Graham J Britton

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

Ethics

Animal experimentation: All animal experiments were carried out under the UK Home Office Project Licence number 30/2705 held by David Wraith and the study was approved by the University of Bristol ethical review committee.

Reviewing Editor

  1. Michael L Dustin, University of Oxford, United Kingdom

Publication history

  1. Received: July 24, 2016
  2. Accepted: January 22, 2017
  3. Accepted Manuscript published: January 23, 2017 (version 1)
  4. Accepted Manuscript updated: January 31, 2017 (version 2)
  5. Version of Record published: February 15, 2017 (version 3)
  6. Version of Record updated: April 5, 2017 (version 4)

Copyright

© 2017, Britton 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. Graham J Britton
  2. Rachel Ambler
  3. Danielle J Clark
  4. Elaine V Hill
  5. Helen M Tunbridge
  6. Kerrie E McNally
  7. Bronwen R Burton
  8. Philomena Butterweck
  9. Catherine Sabatos-Peyton
  10. Lea A Hampton-O'Neil
  11. Paul Verkade
  12. Christoph Wülfing
  13. David Cameron Wraith
(2017)
PKCθ links proximal T cell and Notch signaling through localized regulation of the actin cytoskeleton
eLife 6:e20003.
https://doi.org/10.7554/eLife.20003

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