Abstract

Yeast studies identified two heterohexameric tethering complexes, which consist of 4 shared (Vps11, Vps16, Vps18 and Vps33) and 2 specific subunits: Vps3 and Vps8 (CORVET) versus Vps39 and Vps41 (HOPS). CORVET is an early and HOPS is a late endosomal tether. The function of HOPS is well known in animal cells, while CORVET is poorly characterized. Here we show that Drosophila Vps8 is highly expressed in hemocytes and nephrocytes, and localizes to early endosomes despite the lack of a clear Vps3 homolog. We find that Vps8 forms a complex and acts together with Vps16A, Dor/Vps18 and Car/Vps33A, and loss of any of these proteins leads to fragmentation of endosomes. Surprisingly, Vps11 deletion causes enlargement of endosomes, similar to loss of the HOPS-specific subunits Vps39 and Lt/Vps41. We thus identify a 4 subunit-containing miniCORVET complex as an unconventional early endosomal tether in Drosophila.

Article and author information

Author details

  1. Péter Lőrincz

    Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  2. Zsolt Lakatos

    Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  3. Ágnes Varga

    Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  4. Tamás Maruzs

    Institute of Genetics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  5. Zsófia Simon-Vecsei

    Institute of Genetics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  6. Zsuzsanna Darula

    Laboratory of Proteomics Research, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  7. Péter Benkő

    Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  8. Gábor Csordás

    Institute of Genetics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  9. Mónika Lippai

    Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  10. István Andó

    Institute of Genetics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  11. Krisztina Hegedűs

    Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  12. Katalin F Medzihradszky

    Laboratory of Proteomics Research, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  13. Szabolcs Takáts

    Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
    Competing interests
    The authors declare that no competing interests exist.
  14. Gábor Juhász

    Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
    For correspondence
    szmrt@elte.hu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2016, Lőrincz 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

  • 2,921
    views
  • 555
    downloads
  • 55
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

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)

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

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

  1. Péter Lőrincz
  2. Zsolt Lakatos
  3. Ágnes Varga
  4. Tamás Maruzs
  5. Zsófia Simon-Vecsei
  6. Zsuzsanna Darula
  7. Péter Benkő
  8. Gábor Csordás
  9. Mónika Lippai
  10. István Andó
  11. Krisztina Hegedűs
  12. Katalin F Medzihradszky
  13. Szabolcs Takáts
  14. Gábor Juhász
(2016)
MiniCORVET is a Vps8-containing early endosomal tether in Drosophila
eLife 5:e14226.
https://doi.org/10.7554/eLife.14226

Share this article

https://doi.org/10.7554/eLife.14226

Further reading

    1. Cancer Biology
    2. Cell Biology
    Salam Dabsan, Gali Zur ... Aeid Igbaria
    Research Article

    The endoplasmic reticulum (ER) is an essential sensing organelle responsible for the folding and secretion of almost one-third of eukaryotic cells' total proteins. However, environmental, chemical, and genetic insults often lead to protein misfolding in the ER, accumulating misfolded proteins, and causing ER stress. To solve this, several mechanisms were reported to relieve ER stress by decreasing the ER protein load. Recently, we reported a novel ER surveillance mechanism by which proteins from the secretory pathway are refluxed to the cytosol to relieve the ER of its content. The refluxed proteins gain new prosurvival functions in cancer cells, thereby increasing cancer cell fitness. We termed this phenomenon ER to CYtosol Signaling (or ‘ERCYS’). Here, we found that in mammalian cells, ERCYS is regulated by DNAJB12, DNAJB14, and the HSC70 cochaperone SGTA. Mechanistically, DNAJB12 and DNAJB14 bind HSC70 and SGTA - through their cytosolically localized J-domains to facilitate ER-protein reflux. DNAJB12 is necessary and sufficient to drive this phenomenon to increase AGR2 reflux and inhibit wt-p53 during ER stress. Mutations in DNAJB12/14 J-domain prevent the inhibitory interaction between AGR2-wt-p53. Thus, targeting the DNAJB12/14-HSC70/SGTA axis is a promising strategy to inhibit ERCYS and impair cancer cell fitness.

    1. Cancer Biology
    2. Cell Biology
    Brooke A Conti, Leo Novikov ... Mariano Oppikofer
    Research Article

    DNA base lesions, such as incorporation of uracil into DNA or base mismatches, can be mutagenic and toxic to replicating cells. To discover factors in repair of genomic uracil, we performed a CRISPR knockout screen in the presence of floxuridine, a chemotherapeutic agent that incorporates uracil and fluorouracil into DNA. We identified known factors, such as uracil DNA N-glycosylase (UNG), and unknown factors, such as the N6-adenosine methyltransferase, METTL3, as required to overcome floxuridine-driven cytotoxicity. Visualized with immunofluorescence, the product of METTL3 activity, N6-methyladenosine, formed nuclear foci in cells treated with floxuridine. The observed N6-methyladenosine was embedded in DNA, called 6mA, and these results were confirmed using an orthogonal approach, liquid chromatography coupled to tandem mass spectrometry. METTL3 and 6mA were required for repair of lesions driven by additional base-damaging agents, including raltitrexed, gemcitabine, and hydroxyurea. Our results establish a role for METTL3 and 6mA in promoting genome stability in mammalian cells, especially in response to base damage.