Temporal profiling of redox-dependent heterogeneity in single cells
- The Hebrew University of Jerusalem, Israel
- Weizmann Institute of Science, Israel
Abstract
Cellular redox status affects diverse cellular functions, including proliferation, protein homeostasis, and aging. Thus, individual differences in redox status can give rise to distinct sub-populations even among cells with identical genetic backgrounds. Here, we have created a novel methodology to track redox status at single cell resolution using the redox-sensitive probe Grx1-roGFP2. Our method allows identification and sorting of sub-populations with different oxidation levels in either the cytosol, mitochondria or peroxisomes. Using this approach, we defined a redox-dependent heterogeneity of yeast cells and characterized growth, as well as proteomic and transcriptomic profiles of distinctive redox subpopulations. We report that, starting in late logarithmic growth, cells of the same age have a bi-modal distribution of oxidation status. A comparative proteomic analysis between these populations identified three key proteins, Hsp30, Dhh1, and Pnc1, which affect basal oxidation levels and may serve as first line of defense proteins in redox homeostasis.
Data availability
All data generated or analyses during this study are included in the manuscript and supporting files. Proteomic data was uploadedto the PRIDE database with the dataset identifier PXD009443. Transcriptomic data was uploaded to the GEO database as described in the manuscript (methods).
Article and author information
Author details
Funding
Israel Science Foundation
- Dana Reichmann
Human Frontier Science Program
- Dana Reichmann
European Commission
- Dana Reichmann
US-Binational Science Foundation
- Dana Reichmann
Joint Berlin-Jerusalem postdoc fellowship, Hebrew University and Freie University
- Sidra Ilyas
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Radzinski 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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Temporal profiling of redox-dependent heterogeneity in single cells
eLife 7:e37623.
https://doi.org/10.7554/eLife.37623
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