The linear ubiquitin chain assembly complex LUBAC generates heterotypic ubiquitin chains
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Austria
- Research Institute of Molecular Pathology, Austria
- University of Oxford, United Kingdom
- JT Inc., Japan
- Medical Institute of Bioregulation (MIB), Kyushu University, Japan
Abstract
The linear ubiquitin chain assembly complex (LUBAC) is the only known ubiquitin ligase for linear/Met1-linked ubiquitin chain formation. One of the LUBAC components, HOIL-1L, was recently shown to catalyse oxyester bond formation between ubiquitin and some substrates. However, oxyester bond formation in the context of LUBAC has not been directly observed. Here, we present the first 3D reconstruction of human LUBAC obtained by electron microscopy and report its generation of heterotypic ubiquitin chains containing linear linkages with oxyester-linked branches. We found that this event depends on HOIL-1L catalytic activity. By cross-linking mass spectrometry showing proximity between the catalytic RBR domains, a coordinated ubiquitin relay mechanism between the HOIP and HOIL-1L ligases is suggested. In mouse embryonic fibroblasts, these heterotypic chains were induced by TNF, which is reduced in cells expressing an HOIL-1L catalytic inactive mutant. In conclusion, we demonstrate that LUBAC assembles heterotypic ubiquitin chains by the concerted action of HOIP and HOIL-1L.
Data availability
All data besides the structural data and the mass spec data (see below) generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Supplementary Tables 1-3.wwPDB deposition with dataset ID: D_1292108794ProteomeXchange with identifier PXD019771.
Article and author information
Author details
Funding
Japan Society for the Promotion of Science (JP 18K19959)
- Fumiyo Ikeda
Japan Society for the Promotion of Science (JP 21H04777)
- Fumiyo Ikeda
Japan Society for the Promotion of Science (JP 21H00288)
- Fumiyo Ikeda
Austrian Academy of Sciences
- Fumiyo Ikeda
Boehringer Ingelheim
- David Haselbach
FFG (Headquarter Grant 852936)
- Tim Clausen
Boehringer Ingelheim
- Tim Clausen
European Research Counsil (PHOTOMASS 819593)
- Philipp Kukura
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All mice were bred and maintained in accordance with ethical animal license protocols complying with the Austrian and European legislation. Animal procedures were covered by the license 568809/2013/18.
Copyright
© 2021, Rodriguez Carvajal 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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The linear ubiquitin chain assembly complex LUBAC generates heterotypic ubiquitin chains
eLife 10:e60660.
https://doi.org/10.7554/eLife.60660
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