A WDR35-dependent coat protein complex transports ciliary membrane cargo vesicles to cilia
- MRC Institute of Genetics and Molecular Medicine, United Kingdom
- Aarhus University, Denmark
- MRC Human Genetics Unit, University of Edinburgh, United Kingdom
- Max-Planck Institute of Molecular Cell Biology and Genetics, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics, Germany
- The University of Edinburgh, United Kingdom
- University of Edinburgh, United Kingdom
- Human Technopole, Italy
Abstract
Intraflagellar transport (IFT) is a highly conserved mechanism for motor-driven transport of cargo within cilia, but how this cargo is selectively transported to cilia is unclear. WDR35/IFT121 is a component of the IFT-A complex best known for its role in ciliary retrograde transport. In the absence of WDR35, small mutant cilia form but fail to enrich in diverse classes of ciliary membrane proteins. In Wdr35 mouse mutants, the non-core IFT-A components are degraded and core components accumulate at the ciliary base. We reveal deep sequence homology of WDR35 and other IFT-A subunits to α and ß' COPI coatomer subunits, and demonstrate an accumulation of 'coat-less' vesicles which fail to fuse with Wdr35 mutant cilia. We determine that recombinant non-core IFT-As can bind directly to lipids and provide the first in-situ evidence of a novel coat function for WDR35, likely with other IFT-A proteins, in delivering ciliary membrane cargo necessary for cilia elongation.
Data availability
Source Data (Figures 1B,C; 2B; 3B; as well as Figure 3 Supplement 1C, Figure 7 Supplement-1C) have been uploaded with the submission containing numerical data of all graphs shown in the figures and figure supplements. We have also uploaded the Excel or/and Prism files as source data in addition to the data points which have been referenced, as appropriate in the Figure legends. Source data of raw and full uncropped blots for Figures 3B, C, E and Figure 3 Supplement 1A, as well as Figure 5B, C and Figure 5 Supplement 1 B-D are uploaded as zipped files per figure. For Figure 7F, we have included the ROIs used for calculations uploaded in a single folder including all numerical data of Figure 7 (7B-D,F) graphs at Dryad https://doi.org/10.5061/dryad.m37pvmd33. All analysis tools have been made available on GitHub (https://github.com/IGMM-ImagingFacility/Quidwai2020 WDR35paper), as described in Materials and Methods. Proteomics data files are be uploaded ProteomeXchange (Identifer: PXD022652), with the accession number is available with the paper and is now publically available.Project Name: A WDR35-dependent coatomer transports ciliary membrane proteins from the Golgi to the ciliaProject accession: PXD022652
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Figure 7- source data 1.Dryad Digital Repository, doi:10.5061/dryad.m37pvmd33.
Article and author information
Author details
Funding
European Molecular Biology Laboratory (Short Term Fellowship)
- Tooba Quidwai
European Commission (H2020,Grant Agreement number 888322)
- Narcis A Petriman
Lister Institute of Preventive Medicine (Research Prize Fellow)
- Joseph A Marsh
Novo Nordisk (Grant No. NNF15OC0014164)
- Jiaolong Wang
- Narcis A Petriman
- Esben Lorentzen
Carlsbergfondet (Grant No. CF19-0253)
- Jiaolong Wang
- Narcis A Petriman
- Esben Lorentzen
European Commission (H2020 Grant No. 819826)
- Weihua Leng
- Petra Kiesel
- Gaia Pigino
European Commission (H2020 No. 866355)
- Tooba Quidwai
- Emma A Hall
- Pleasantine Mill
Medical Research Council (Core unit funding No. MC_UU_12018/26)
- Tooba Quidwai
- Emma A Hall
- Laura C Murphy
- Margaret A Keighren
- Pleasantine Mill
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: We followed international, national and institutional guidelines for the care and use of animals. Animal experiments were carried out under UK Home Office Project Licenses PPL 60/4424, PB0DC8431 and P18921CDE in facilities at the University of Edinburgh (PEL 60/2605) and were approved by the University of Edinburgh animal welfare and ethical review body.
Copyright
© 2021, Quidwai 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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A WDR35-dependent coat protein complex transports ciliary membrane cargo vesicles to cilia
eLife 10:e69786.
https://doi.org/10.7554/eLife.69786
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