An aging-independent replicative lifespan in a symmetrically dividing eukaryote
Abstract
The replicative lifespan (RLS) of a cell-defined as the number of cell divisions before death-has informed our understanding of the mechanisms of cellular aging. However, little is known about aging and longevity in symmetrically dividing eukaryotic cells because most prior studies have used budding yeast for RLS studies. Here, we describe a multiplexed fission yeast lifespan micro-dissector (multFYLM) and an associated image processing pipeline for performing high-throughput and automated single-cell micro-dissection. Using the multFYLM, we observe continuous replication of hundreds of individual fission yeast cells for over seventy-five generations. Surprisingly, cells die without the classic hallmarks of cellular aging, such as progressive changes in size, doubling time, or sibling health. Genetic perturbations and drugs can extend the RLS via an aging-independent mechanism. Using a quantitative model to analyze these results, we conclude that fission yeast does not age and that cellular aging and replicative lifespan can be uncoupled in a eukaryotic cell.
Data availability
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The genome sequence of Schizosaccharomyces pombePublicly available at the NCBI Nucleotide (sccession no: CU329670.1).
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The genome sequence of Schizosaccharomyces pombePublicly available at the NCBI Nucleotide (sccession no: CU329671.1).
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The genome sequence of Schizosaccharomyces pombePublicly available at the NCBI Nucleotide (sccession no: CU329672.1).
Article and author information
Author details
Funding
American Federation for Aging Research (AFAR-020)
- Eric C Spivey
- Stephen K Jones
- James R Rybarski
- Fatema A Saifuddin
- Ilya J Finkelstein
National Institute on Aging (F32 AG053051)
- Stephen K Jones
Cancer Prevention and Research Institute of Texas (R1214)
- James R Rybarski
- Fatema A Saifuddin
- Ilya J Finkelstein
Welch Foundation (F-l808)
- Eric C Spivey
- Stephen K Jones
- James R Rybarski
- Fatema A Saifuddin
- Ilya J Finkelstein
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Spivey 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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