1. Cell Biology

An aging-independent replicative lifespan in a symmetrically dividing eukaryote

  1. Eric C Spivey
  2. Stephen K Jones
  3. James R Rybarski
  4. Fatema A Saifuddin
  5. Ilya J Finkelstein  Is a corresponding author
  1. The University of Texas at Austin, United States
https://doi.org/10.7554/eLife.20340
Share this article
Cite this article
  1. Eric C Spivey
  2. Stephen K Jones
  3. James R Rybarski
  4. Fatema A Saifuddin
  5. Ilya J Finkelstein
(2017)
An aging-independent replicative lifespan in a symmetrically dividing eukaryote
eLife 6:e20340.
https://doi.org/10.7554/eLife.20340
  2. Download BibTeX
  3. Download .RIS

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

The following previously published data sets were used
    1. Wood et al.
    (2002) The genome sequence of Schizosaccharomyces pombe
    Publicly available at the NCBI Nucleotide (sccession no: CU329670.1).
    https://www.ncbi.nlm.nih.gov/nuccore/CU329670.1
    1. Wood et al.
    (2002) The genome sequence of Schizosaccharomyces pombe
    Publicly available at the NCBI Nucleotide (sccession no: CU329671.1).
    https://www.ncbi.nlm.nih.gov/nuccore/CU329671.1
    1. Wood et al.
    (2002) The genome sequence of Schizosaccharomyces pombe
    Publicly available at the NCBI Nucleotide (sccession no: CU329672.1).
    https://www.ncbi.nlm.nih.gov/nuccore/CU329672.1

Article and author information

Author details

  1. Eric C Spivey

    Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4080-8616

  2. Stephen K Jones

    Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. James R Rybarski

    Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Fatema A Saifuddin

    Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Ilya J Finkelstein

    Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
    For correspondence
    ifinkelstein@cm.utexas.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9371-2431

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.

Metrics

  • 4,569
    views
  • 764
    downloads
  • 34
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

Share this article

https://doi.org/10.7554/eLife.20340

Categories and tags

Research organism

Further reading

    1. Cancer Biology
    2. Cell Biology

    N6-methyladenosine in DNA promotes genome stability

    Brooke A Conti, Leo Novikov ... Mariano Oppikofer
    Research Article

    DNA base lesions, such as incorporation of uracil into DNA or base mismatches, can be mutagenic and toxic to replicating cells. To discover factors in repair of genomic uracil, we performed a CRISPR knockout screen in the presence of floxuridine, a chemotherapeutic agent that incorporates uracil and fluorouracil into DNA. We identified known factors, such as uracil DNA N-glycosylase (UNG), and unknown factors, such as the N6-adenosine methyltransferase, METTL3, as required to overcome floxuridine-driven cytotoxicity. Visualized with immunofluorescence, the product of METTL3 activity, N6-methyladenosine, formed nuclear foci in cells treated with floxuridine. The observed N6-methyladenosine was embedded in DNA, called 6mA, and these results were confirmed using an orthogonal approach, liquid chromatography coupled to tandem mass spectrometry. METTL3 and 6mA were required for repair of lesions driven by additional base-damaging agents, including raltitrexed, gemcitabine, and hydroxyurea. Our results establish a role for METTL3 and 6mA in promoting genome stability in mammalian cells, especially in response to base damage.

    1. Cell Biology

    Stratification of enterochromaffin cells by single-cell expression analysis

    Yan Song, Linda J Fothergill ... Gene W Yeo
    Research Article

    Dynamic interactions between gut mucosal cells and the external environment are essential to maintain gut homeostasis. Enterochromaffin (EC) cells transduce both chemical and mechanical signals and produce 5-hydroxytryptamine to mediate disparate physiological responses. However, the molecular and cellular basis for functional diversity of ECs remains to be adequately defined. Here, we integrated single-cell transcriptomics with spatial image analysis to identify 14 EC clusters that are topographically organized along the gut. Subtypes predicted to be sensitive to the chemical environment and mechanical forces were identified that express distinct transcription factors and hormones. A Piezo2+ population in the distal colon was endowed with a distinctive neuronal signature. Using a combination of genetic, chemogenetic, and pharmacological approaches, we demonstrated Piezo2+ ECs are required for normal colon motility. Our study constructs a molecular map for ECs and offers a framework for deconvoluting EC cells with pleiotropic functions.

    1. Cell Biology

    Small-molecule activation of TFEB alleviates Niemann–Pick disease type C via promoting lysosomal exocytosis and biogenesis

    Kaili Du, Hongyu Chen ... Dan Li
    Research Article

    Niemann–Pick disease type C (NPC) is a devastating lysosomal storage disease characterized by abnormal cholesterol accumulation in lysosomes. Currently, there is no treatment for NPC. Transcription factor EB (TFEB), a member of the microphthalmia transcription factors (MiTF), has emerged as a master regulator of lysosomal function and promoted the clearance of substrates stored in cells. However, it is not known whether TFEB plays a role in cholesterol clearance in NPC disease. Here, we show that transgenic overexpression of TFEB, but not TFE3 (another member of MiTF family) facilitates cholesterol clearance in various NPC1 cell models. Pharmacological activation of TFEB by sulforaphane (SFN), a previously identified natural small-molecule TFEB agonist by us, can dramatically ameliorate cholesterol accumulation in human and mouse NPC1 cell models. In NPC1 cells, SFN induces TFEB nuclear translocation via a ROS-Ca2+-calcineurin-dependent but MTOR-independent pathway and upregulates the expression of TFEB-downstream genes, promoting lysosomal exocytosis and biogenesis. While genetic inhibition of TFEB abolishes the cholesterol clearance and exocytosis effect by SFN. In the NPC1 mouse model, SFN dephosphorylates/activates TFEB in the brain and exhibits potent efficacy of rescuing the loss of Purkinje cells and body weight. Hence, pharmacological upregulating lysosome machinery via targeting TFEB represents a promising approach to treat NPC and related lysosomal storage diseases, and provides the possibility of TFEB agonists, that is, SFN as potential NPC therapeutic candidates.