Abstract

Regnase-1 is an endoribonuclease crucial for controlling inflammation by degrading mRNAs encoding cytokines and inflammatory mediators in mammals. However, it is unclear how Regnase-1-mediated mRNA decay is controlled in interleukin (IL)-1β- or Toll-like receptor (TLR) ligand-stimulated cells. Here, by analyzing the Regnase-1 interactome, we found that IL-1β or TLR stimulus dynamically induced the formation of Regnase-1-β-transducin repeat-containing protein (βTRCP) complex. Importantly, we also uncovered a novel interaction between Regnase-1 and 14-3-3 in both mouse and human cells. In IL-1R/TLR-stimulated cells, the Regnase-1-14-3-3 interaction is mediated by IRAK1 through a previously uncharacterized C-terminal structural domain. Phosphorylation of Regnase-1 at S494 and S513 is critical for Regnase-1-14-3-3 interaction, while a different set of phosphorylation sites of Regnase-1 is known to be required for the recognition by βTRCP and proteasome-mediated degradation. We found that Regnase-1-14-3-3 and Regnase-1-βTRCP interactions are not sequential events. Rather, 14-3-3 protects Regnase-1 from βTRCP-mediated degradation. On the other hand, 14-3-3 abolishes Regnase-1-mediated mRNA decay by inhibiting Regnase-1-mRNA association. In addition, nuclear-cytoplasmic shuttling of Regnase-1 is abrogated by 14-3-3 interaction. Taken together, the results suggest that a novel inflammation-induced interaction of 14-3-3 with Regnase-1 stabilizes inflammatory mRNAs by sequestering Regnase-1 in the cytoplasm to prevent mRNA recognition.

Data availability

Mass spectrometry data (PXD026561) is available athttps://repository.jpostdb.org/preview/39625605260bf241f327a9Access key: 8668RNA sequencing data (GSE180028) is available athttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE180028Secure token: urknaskkjjsflsj

The following data sets were generated

Article and author information

Author details

  1. Kotaro Akaki

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0059-3291
  2. Kosuke Ogata

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0634-3990
  3. Yuhei Yamauchi

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
  4. Noriki Iwai

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
  5. Ka Man Tse

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
  6. Fabian Hia

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7209-4312
  7. Atsushi Mochizuki

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
  8. Yasushi Ishihama

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7714-203X
  9. Takashi Mino

    Kyoto University, Kyoto, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9562-008X
  10. Osamu Takeuchi

    Kyoto University, Kyoto, Japan
    For correspondence
    otake@mfour.med.kyoto-u.ac.jp
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1260-6232

Funding

Japan Society for the Promotion of Science (19H03488)

  • Osamu Takeuchi

Japan Agency for Medical Research and Development (JP20gm4010002)

  • Osamu Takeuchi

Japan Society for the Promotion of Science (19H03488)

  • Takashi Mino

Japan Society for the Promotion of Science (Core-to-Core Program)

  • Osamu Takeuchi

Japan Society for the Promotion of Science (221S0002)

  • Takashi Mino

Japan Society for the Promotion of Science (16H06279)

  • Takashi Mino

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

Reviewing Editor

  1. Nahum Sonenberg, McGill University, Canada

Ethics

Animal experimentation: All animal experiments were conducted in compliance with the guidelines of the Kyoto University animal experimentation committee. (Approval number: MedKyo21057)

Version history

  1. Received: July 6, 2021
  2. Preprint posted: July 15, 2021 (view preprint)
  3. Accepted: October 8, 2021
  4. Accepted Manuscript published: October 12, 2021 (version 1)
  5. Accepted Manuscript updated: October 13, 2021 (version 2)
  6. Version of Record published: October 28, 2021 (version 3)

Copyright

© 2021, Akaki 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. Kotaro Akaki
  2. Kosuke Ogata
  3. Yuhei Yamauchi
  4. Noriki Iwai
  5. Ka Man Tse
  6. Fabian Hia
  7. Atsushi Mochizuki
  8. Yasushi Ishihama
  9. Takashi Mino
  10. Osamu Takeuchi
(2021)
IRAK1-dependent Regnase-1-14-3-3 complex formation controls Regnase-1-mediated mRNA decay
eLife 10:e71966.
https://doi.org/10.7554/eLife.71966

Share this article

https://doi.org/10.7554/eLife.71966

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