Regulation of canonical Wnt signalling by the ciliopathy protein MKS1 and the E2 ubiquitin-conjugating enzyme UBE2E1
- University of Leeds, United Kingdom
- University of Tübingen, Germany
- University of Southampton, United Kingdom
Abstract
Primary ciliary defects cause a group of developmental conditions known as ciliopathies. Here, we provide mechanistic insight into ciliary ubiquitin processing in cells and for mouse model lacking the ciliary protein Mks1. In vivo loss of Mks1 sensitizes cells to proteasomal disruption, leading to abnormal accumulation of ubiquitinated proteins. We identified UBE2E1, an E2 ubiquitin-conjugating enzyme that polyubiquitinates β-catenin, and RNF34, an E3 ligase, as novel interactants of MKS1. UBE2E1 and MKS1 colocalized, and loss of UBE2E1 recapitulates the ciliary and Wnt signalling phenotypes observed during loss of MKS1. Levels of UBE2E1 and MKS1 are co-dependent and UBE2E1 mediates both regulatory and degradative ubiquitination of MKS1. We demonstrate that processing of phosphorylated β-catenin occurs at the ciliary base through the functional interaction between UBE2E1 and MKS1. These observations suggest that correct β-catenin levels are tightly regulated at the primary cilium by a ciliary-specific E2 (UBE2E1) and a regulatory substrate-adaptor (MKS1).
Data availability
Data generated or analysed during this study are included in the manuscript and supporting files. Source data is provided for Supplementary Dataset 1, Figure 4e-f, and for all gels and blots displayed in Figures 1-7 (apart from Figure 1e, Figure 1-figure supplement 1 panel e for beta-actin western, Figure 4-figure supplement 1 panel a). Imaging data for gels and blots is collated as both original files of the full unedited files, and figures with the uncropped gels or blots with the relevant bands highlighted.Data from Supplementary dataset 1 is also available from University of Leeds at https://doi.org/10.5518/814
Article and author information
Author details
Katarzyna Szymanska
Funding
Medical Research Council (MR/M000532/1)
- Colin A Johnson
FP7 Health (241955 SYSCILIA)
- Colin A Johnson
Wellcome Trust (204378/Z/16/Z)
- Gabrielle Wheway
Wellcome Trust (105615/Z/14/Z)
- Katarzyna Szymanska
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The animal studies described in this paper were carried out under the guidance issued by the Medical Research Council in Responsibility in the Use of Animals for Medical Research (July 1993) in accordance with UK Home Office regulations under the Project Licence no. PPL40/3349.
Human subjects: Informed consent was obtained from all participating families or patients, with studies approved by the Leeds (East) Research Ethics Committee (REC ref. no. 08/H1306/85) on 4th July 2008.
Copyright
© 2022, Szymanska 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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Regulation of canonical Wnt signalling by the ciliopathy protein MKS1 and the E2 ubiquitin-conjugating enzyme UBE2E1
eLife 11:e57593.
https://doi.org/10.7554/eLife.57593
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