Genetic profiling of protein burden and nuclear export overload
Abstract
Overproduction (op) of proteins triggers cellular defects. One of the consequences of overproduction is the protein burden/cost, which is produced by an overloading of the protein synthesis process. However, the physiology of cells under a protein burden is not well characterized. We performed genetic profiling of protein burden by systematic analysis of genetic interactions between GFP-op, surveying both deletion and temperature-sensitive mutants in budding yeast. We also performed genetic profiling in cells with overproduction of triple-GFP (tGFP), and the nuclear export signal-containing tGFP (NES-tGFP). The mutants specifically interacted with GFP-op were suggestive of unexpected connections between actin-related processes like polarization and the protein burden, which was supported by morphological analysis. The tGFP-op interactions suggested that this protein probe overloads the proteasome, whereas those that interacted with NES-tGFP involved genes encoding components of the nuclear export process, providing a resource for further analysis of the protein burden and nuclear export overload.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
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Funding
Japan Society for the Promotion of Science (17H03618)
- Hisao Moriya
Japan Society for the Promotion of Science (15KK0258)
- Hisao Moriya
Japan Society for the Promotion of Science (18K19300)
- Hisao Moriya
Japan Society for the Promotion of Science (20H03242)
- Hisao Moriya
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Nir Ben-Tal, Tel Aviv University, Israel
Version history
- Received: December 2, 2019
- Accepted: November 1, 2020
- Accepted Manuscript published: November 4, 2020 (version 1)
- Version of Record published: November 18, 2020 (version 2)
Copyright
© 2020, Kintaka 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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