1. Biochemistry and Chemical Biology
  2. Cell Biology
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Sorting of a multi-subunit ubiquitin ligase complex in the endolysosome system

  1. Xi Yang
  2. Felichi Mae Arines
  3. Weichao Zhang
  4. Ming Li  Is a corresponding author
  1. University of Michigan, United States
Research Article
  • Cited 14
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Cite this article as: eLife 2018;7:e33116 doi: 10.7554/eLife.33116

Abstract

The yeast Dsc E3 ligase complex has long been recognized as a Golgi-specific protein ubquitination system. It shares a striking sequence similarity to the Hrd1 complex that plays critical roles in the ER-associated degradation pathway. Using biochemical purification and mass spectrometry, we identified two novel Dsc subunits, which we named as Gld1 and Vld1. Surprisingly, Gld1 and Vld1 do not coexist in the same complex. Instead, they compete with each other to form two functionally independent Dsc subcomplexes. The Vld1 subcomplex takes the AP3 pathway to reach the vacuole membrane, whereas the Gld1 subcomplex travels through the VPS pathway and is cycled between Golgi and endosomes by the retromer. Thus, instead of being Golgi-specific, the Dsc complex can regulate protein levels at three distinct organelles, namely Golgi, endosome, and vacuole. Our study provides a novel model of achieving multi-tasking for transmembrane ubiquitin ligases with interchangeable trafficking adaptors.

Article and author information

Author details

  1. Xi Yang

    Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Felichi Mae Arines

    Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5770-3116
  3. Weichao Zhang

    Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Ming Li

    Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
    For correspondence
    mlium@umich.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1247-2377

Funding

University of Michigan (Startup fund)

  • Ming Li

University of Michigan (MCubed fund)

  • Ming Li

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

Reviewing Editor

  1. Christopher G Burd, Yale School of Medicine, United States

Publication history

  1. Received: October 27, 2017
  2. Accepted: January 19, 2018
  3. Accepted Manuscript published: January 22, 2018 (version 1)
  4. Version of Record published: February 13, 2018 (version 2)

Copyright

© 2018, Yang 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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