1. Biochemistry and Chemical Biology
  2. Cell Biology
Download icon

Cell-based HTS identifies a chemical chaperone for preventing ER protein aggregation and proteotoxicity

  1. Keisuke Kitakaze
  2. Shusuke Taniuchi
  3. Eri Kawano
  4. Yoshimasa Hamada
  5. Masato Miyake
  6. Miho Oyadomari
  7. Hirotatsu Kojima
  8. Hidetaka Kosako
  9. Tomoko Kuribara
  10. Suguru Yoshida
  11. Takamitsu Hosoya
  12. Seiichi Oyadomari  Is a corresponding author
  1. Tokushima University, Japan
  2. The University of Tokyo, Japan
  3. Tokyo Medical and Dental University (TMDU), Japan
Research Article
  • Cited 3
  • Views 2,690
  • Annotations
Cite this article as: eLife 2019;8:e43302 doi: 10.7554/eLife.43302

Abstract

The endoplasmic reticulum (ER) is responsible for folding secretory and membrane proteins, but disturbed ER proteostasis may lead to protein aggregation and subsequent cellular and clinical pathologies. Chemical chaperones have recently emerged as a potential therapeutic approach for ER stress-related diseases. Here, we identified 2-phenylimidazo[2,1-b]benzothiazole derivatives (IBTs) as chemical chaperones in a cell-based high-throughput screen. Biochemical and chemical biology approaches revealed that IBT21 directly binds to unfolded or misfolded proteins and inhibits protein aggregation. Finally, IBT21 prevented cell death caused by chemically induced ER stress and by a proteotoxin, an aggression-prone prion protein. Taken together, our data show the promise of IBTs as potent chemical chaperones that can ameliorate diseases resulting from protein aggregation under ER stress.

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. Keisuke Kitakaze

    Division of Molecular Biology, Institute for Genome Research, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4852-1257
  2. Shusuke Taniuchi

    Division of Molecular Biology, Institute for Genome Research, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
    Competing interests
    The authors declare that no competing interests exist.
  3. Eri Kawano

    Division of Molecular Biology, Institute for Genome Research, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
    Competing interests
    The authors declare that no competing interests exist.
  4. Yoshimasa Hamada

    Division of Molecular Biology, Institute for Genome Research, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
    Competing interests
    The authors declare that no competing interests exist.
  5. Masato Miyake

    Division of Molecular Biology, Institute for Genome Research, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
    Competing interests
    The authors declare that no competing interests exist.
  6. Miho Oyadomari

    Division of Molecular Biology, Institute for Genome Research, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
    Competing interests
    The authors declare that no competing interests exist.
  7. Hirotatsu Kojima

    Drug Discovery Initiative (DDI), The University of Tokyo, Tokyo, Japan
    Competing interests
    The authors declare that no competing interests exist.
  8. Hidetaka Kosako

    Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
    Competing interests
    The authors declare that no competing interests exist.
  9. Tomoko Kuribara

    Laboratory of Chemical Bioscience, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
    Competing interests
    The authors declare that no competing interests exist.
  10. Suguru Yoshida

    Laboratory of Chemical Bioscience, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5888-9330
  11. Takamitsu Hosoya

    Laboratory of Chemical Bioscience, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
    Competing interests
    The authors declare that no competing interests exist.
  12. Seiichi Oyadomari

    Division of Molecular Biology, Institute for Genome Research, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
    For correspondence
    oyadomar@tokushima-u.ac.jp
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6766-1485

Funding

Japan Agency for Medical Research and Development (JP18nk0101336)

  • Seiichi Oyadomari

Japan Agency for Medical Research and Development (JP17am0101086)

  • Hirotatsu Kojima

Platform Project for Supporting Drug Discovery and Life Science Research, Basis for Supporting Innovative Drug Discovery and Life Science Research (JP18am0101098)

  • Takamitsu Hosoya

a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (16H05222)

  • Seiichi Oyadomari

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

Reviewing Editor

  1. Matthew D Shoulders, Massachusetts Institute of Technology, United States

Publication history

  1. Received: November 1, 2018
  2. Accepted: November 24, 2019
  3. Accepted Manuscript published: December 17, 2019 (version 1)
  4. Version of Record published: December 19, 2019 (version 2)

Copyright

© 2019, Kitakaze 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

  • 2,690
    Page views
  • 406
    Downloads
  • 3
    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)

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)

  1. Further reading

Further reading

    1. Biochemistry and Chemical Biology
    2. Microbiology and Infectious Disease
    Giulia Bandini et al.
    Research Article Updated

    Fucose is a common component of eukaryotic cell-surface glycoconjugates, generally added by Golgi-resident fucosyltransferases. Whereas fucosylated glycoconjugates are rare in kinetoplastids, the biosynthesis of the nucleotide sugar GDP-Fuc has been shown to be essential in Trypanosoma brucei. Here we show that the single identifiable T. brucei fucosyltransferase (TbFUT1) is a GDP-Fuc: β-D-galactose α-1,2-fucosyltransferase with an apparent preference for a Galβ1,3GlcNAcβ1-O-R acceptor motif. Conditional null mutants of TbFUT1 demonstrated that it is essential for both the mammalian-infective bloodstream form and the insect vector-dwelling procyclic form. Unexpectedly, TbFUT1 was localized in the mitochondrion of T. brucei and found to be required for mitochondrial function in bloodstream form trypanosomes. Finally, the TbFUT1 gene was able to complement a Leishmania major mutant lacking the homologous fucosyltransferase gene (Guo et al., 2021). Together these results suggest that kinetoplastids possess an unusual, conserved and essential mitochondrial fucosyltransferase activity that may have therapeutic potential across trypanosomatids.

    1. Biochemistry and Chemical Biology
    2. Structural Biology and Molecular Biophysics
    Maren Heimhalt et al.
    Research Article

    The mTORC1 kinase complex regulates cell growth, proliferation, and survival. Because mis-regulation of DEPTOR, an endogenous mTORC1 inhibitor, is associated with some cancers, we reconstituted mTORC1 with DEPTOR to understand its function. We find that DEPTOR is a unique partial mTORC1 inhibitor that may have evolved to preserve feedback inhibition of PI3K. Counterintuitively, mTORC1 activated by RHEB or oncogenic mutation is much more potently inhibited by DEPTOR. Although DEPTOR partially inhibits mTORC1, mTORC1 prevents this inhibition by phosphorylating DEPTOR, a mutual antagonism that requires no exogenous factors. Structural analyses of the mTORC1/DEPTOR complex showed DEPTOR’s PDZ domain interacting with the mTOR FAT region, and the unstructured linker preceding the PDZ binding to the mTOR FRB domain. The linker and PDZ form the minimal inhibitory unit, but the N-terminal tandem DEP domains also significantly contribute to inhibition.