In vivo proteomic mapping through GFP-directed proximity-dependent biotin labelling in zebrafish
Abstract
Protein interaction networks are crucial for complex cellular processes. However, the elucidation of protein interactions occurring within highly specialised cells and tissues is challenging. Here we describe the development, and application, of a new method for proximity-dependent biotin labelling in whole zebrafish. Using a conditionally stabilised GFP-binding nanobody to target a biotin ligase to GFP-labelled proteins of interest, we show tissue-specific proteomic profiling using existing GFP-tagged transgenic zebrafish lines. We demonstrate the applicability of this approach, termed BLITZ (Biotin Labelling In Tagged Zebrafish), in diverse cell types such as neurons and vascular endothelial cells. We applied this methodology to identify interactors of caveolar coat protein, cavins, in skeletal muscle. Using this system, we defined specific interaction networks within in vivo muscle cells for the closely related but functionally distinct Cavin4 and Cavin1 proteins.
Data availability
All data generated or analysed during this study are included in the manuscript and supplementary files. Source data files have been provided for Figures 1, 2, 4 and 5
Article and author information
Author details
Funding
National Health and Medical Research Council (569542)
- Robert G Parton
National Health and Medical Research Council (1045092)
- Robert G Parton
National Health and Medical Research Council (APP1044041)
- Robert G Parton
National Health and Medical Research Council (APP1099251)
- Robert G Parton
- Thomas E Hall
Australian Research Council (DP200102559)
- Robert G Parton
- Thomas E Hall
Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology (CE140100036)
- Robert G Parton
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Lilianna Solnica-Krezel, Washington University School of Medicine, United States
Ethics
Animal experimentation: This study was approved by Institutional Biosafety Committee, Office of the Gene Technology Regulator, Australian Government Department of Health, and Molecular Biosciences Animal Ethics Committees, the University of Queensland. The ethics approval numbers are IMB/271/19/BREED and IMB/326/17. IBC/OGTR approval number are IBC/1080/IMB/2017.
Version history
- Received: November 5, 2020
- Accepted: February 15, 2021
- Accepted Manuscript published: February 16, 2021 (version 1)
- Version of Record published: February 22, 2021 (version 2)
Copyright
© 2021, Xiong 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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