2. Academic Validation
  3. A high-coverage shRNA screen identifies TMEM129 as an E3 ligase involved in ER-associated protein degradation

A high-coverage shRNA screen identifies TMEM129 as an E3 ligase involved in ER-associated protein degradation

  • Nat Commun. 2014 May 8;5:3832. doi: 10.1038/ncomms4832.
Michael L van de Weijer 1,  Michael C Bassik 2,  Rutger D Luteijn 1,  Cornelia M Voorburg 1,  Mirjam A M Lohuis 1,  Elisabeth Kremmer 3,  Rob C Hoeben 4,  Emily M LeProust 5,  Siyuan Chen 5,  Hanneke Hoelen 1,  Maaike E Ressing 6,  Weronika Patena 7,  Jonathan S Weissman 8,  Michael T McManus 9,  Emmanuel J H J Wiertz 10,  Robert Jan Lebbink 10
Affiliations

Affiliations

  • 1 Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands.
  • 2 1] Department of Cellular and Molecular Pharmacology, California Institute for Quantitative Biomedical Research, Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA [2].
  • 3 Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Molecular Immunology, 81377 Munich, Germany.
  • 4 Department of Molecular Cell Biology, Leiden University Medical Center, 2333ZC Leiden, The Netherlands.
  • 5 1] Genomics Solution Unit, Agilent Technologies Inc., Santa Clara, California 95051, USA [2].
  • 6 1] Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands [2] Department of Molecular Cell Biology, Leiden University Medical Center, 2333ZC Leiden, The Netherlands.
  • 7 1] Department of Cellular and Molecular Pharmacology, California Institute for Quantitative Biomedical Research, Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA [2] Department of Microbiology and Immunology, University of California, San Francisco, California 94143, USA [3].
  • 8 Department of Cellular and Molecular Pharmacology, California Institute for Quantitative Biomedical Research, Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA.
  • 9 Department of Microbiology and Immunology, University of California, San Francisco, California 94143, USA.
  • 10 1] Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands [2].
PMID: 24807418 DOI: 10.1038/ncomms4832
Abstract

Misfolded ER proteins are retrotranslocated into the cytosol for degradation via the ubiquitin-proteasome system. The human cytomegalovirus protein US11 exploits this ER-associated protein degradation (ERAD) pathway to downregulate HLA class I molecules in virus-infected cells, thereby evading elimination by cytotoxic T-lymphocytes. US11-mediated degradation of HLA class I has been instrumental in the identification of key components of mammalian ERAD, including Derlin-1, p97, VIMP and SEL1L. Despite this, the process governing retrotranslocation of the substrate is still poorly understood. Here using a high-coverage genome-wide shRNA library, we identify the uncharacterized protein TMEM129 and the ubiquitin-conjugating E2 Enzyme UBE2J2 to be essential for US11-mediated HLA class I downregulation. TMEM129 is an unconventional C4C4-type RING finger E3 ubiquitin ligase that resides within a complex containing various other ERAD components, including Derlin-1, Derlin-2, VIMP and p97, indicating that TMEM129 is an integral part of the ER-resident dislocation complex mediating US11-induced HLA class I degradation.

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