Monitoring single-cell dynamics of entry into quiescence during an unperturbed lifecycle
Abstract
The life cycle of microorganisms is associated with dynamic metabolic transitions and complex cellular responses. In yeast, how metabolic signals control the progressive choreography of structural reorganizations observed in quiescent cells during a natural life cycle remains unclear. We have developed an integrated microfluidic device to address this question, enabling continuous single-cell tracking in a batch culture experiencing unperturbed nutrient exhaustion to unravel the coordination between metabolic and structural transitions within cells. Our technique reveals an abrupt fate divergence in the population, whereby a fraction of cells is unable to transition to respiratory metabolism and undergoes a reversible entry into a quiescence-like state leading to premature cell death. Further observations reveal that non-monotonous internal pH fluctuations in respiration-competent cells orchestrate the successive waves of protein super-assemblies formation that accompany the entry into a bona fide quiescent state. This ultimately leads to an abrupt cytosolic glass transition that occurs stochastically long after proliferation cessation. This new experimental framework provides a unique way to track single-cell fate dynamics over a long timescale in a population of cells that continuously modify their ecological niche.
Data availability
The CAD file used to generate the microfluidic device is available on a github repository. The source data used to make the panels (excluding raw image files) are included for each figure. Due to size constraints representative raw image data for Figure 1 is available at Zenodo (https://doi.org/10.5281/zenodo.5592983) and the remaining raw image data, including files for Figures 2 and 3, are available on request from the corresponding author.
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Dataset pHluorin cells experiencing entry into quiescenceZenodo, doi:10.5281/zenodo.5592983.
Article and author information
Author details
Funding
Fondation pour la Recherche Médicale
- Basile Jacquel
Agence Nationale de la Recherche
- Théo Aspert
Agence Nationale de la Recherche
- Gilles Charvin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Jacquel 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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