Human cytomegalovirus interactome analysis identifies degradation hubs, domain associations and viral protein functions
- University of Cambridge, United Kingdom
- MRC-University of Glasgow Centre for Virus Research, United Kingdom
- Cardiff University School of Medicine, United Kingdom
- Harvard Medical School, United States
Abstract
Human cytomegalovirus (HCMV) extensively modulates host cells, downregulating >900 human proteins during viral replication and degrading ≥133 proteins shortly after infection. The mechanism of degradation of most host proteins remains unresolved, and the functions of many viral proteins are incompletely characterised. We performed a mass spectrometry-based interactome analysis of 169 tagged, stably-expressed canonical strain Merlin HCMV proteins, and two non-canonical HCMV proteins, in infected cells. This identified a network of >3,400 virus-host and >150 virus-virus protein interactions, providing insights into functions for multiple viral genes. Domain analysis predicted binding of the viral UL25 protein to SH3 domains of NCK Adaptor Protein-1. Viral interacting proteins were identified for 31/133 degraded host targets. Finally, the uncharacterised, non-canonical ORFL147C protein was found to interact with elements of the mRNA splicing machinery, and a mutational study suggested its importance in viral replication. The interactome data will be important for future studies of herpesvirus infection.
Data availability
All data analysed during this study are included in the manuscript and supporting files. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (http://www.proteomexchange.org/) via the PRIDE (Vizcaino et al., 2016) partner repository with the dataset identifier PXD014845.
Article and author information
Author details
Gavin WG Wilkinson
Funding
Wellcome (108070/Z/15/Z)
- Michael P Weekes
Medical Research Council (MR/L018373/1)
- Eddie CY Wang
- Gavin WG Wilkinson
- Richard J Stanton
Medical Research Council (MR/P001602/1)
- Eddie CY Wang
- Gavin WG Wilkinson
- Richard J Stanton
Wellcome (WT090323MA)
- Eddie CY Wang
- Gavin WG Wilkinson
- Richard J Stanton
Medical Research Council (MC_UU_12014/3)
- Andrew J Davison
National Institutes of Health (U24 HG006673)
- Edward L Huttlin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Nobre 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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Human cytomegalovirus interactome analysis identifies degradation hubs, domain associations and viral protein functions
eLife 8:e49894.
https://doi.org/10.7554/eLife.49894
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