Transgenerational dynamics of rDNA copy number in Drosophila male germline stem cells

Abstract

rDNA loci, composed of hundreds of tandemly duplicated arrays of rRNA genes, are known to be among the most unstable genetic elements due to their repetitive nature. rDNA instability underlies aging (replicative senescence) in yeast cells, however, its contribution to the aging of multicellular organisms is poorly understood. In this study, we investigate the dynamics of rDNA loci during aging in the Drosophila male germline stem cell (GSC) lineage, and show that rDNA copy number decreases during aging. Our study further reveals that this age-dependent decrease in rDNA copy number is heritable from generation to generation, yet GSCs in young animals that inherited reduced rDNA copy number are capable of recovering normal rDNA copy number. Based on these findings, we propose that rDNA loci are dynamic genetic elements, where rDNA copy number changes dynamically yet is maintained through a recovery mechanism in the germline.

Article and author information

Author details

  1. Kevin L Lu

    Life Sciences Institute, University of Michigan, Ann Arbor, United States
    Competing interests
    No competing interests declared.
  2. Jonathan O Nelson

    Life Sciences Institute, University of Michigan, Ann Arbor, United States
    Competing interests
    No competing interests declared.
  3. George J Watase

    Life Sciences Institute, University of Michigan, Ann Arbor, United States
    Competing interests
    No competing interests declared.
  4. Natalie Warsinger-Pepe

    Life Sciences Institute, University of Michigan, Ann Arbor, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9375-8990
  5. Yukiko M Yamashita

    Life Sciences Institute, University of Michigan, Ann Arbor, United States
    For correspondence
    yukikomy@umich.edu
    Competing interests
    Yukiko M Yamashita, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5541-0216

Funding

Howard Hughes Medical Institute

  • Yukiko M Yamashita

National Institute of General Medical Sciences

  • Yukiko M Yamashita

National Institute on Aging

  • Kevin L Lu

National Institute of Child Health and Human Development

  • Natalie Warsinger-Pepe

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Allan C Spradling, Howard Hughes Medical Institute, Carnegie Institution for Science, United States

Version history

  1. Received: September 30, 2017
  2. Accepted: January 19, 2018
  3. Accepted Manuscript published: February 13, 2018 (version 1)
  4. Version of Record published: February 13, 2018 (version 2)

Copyright

© 2018, Lu 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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  1. Kevin L Lu
  2. Jonathan O Nelson
  3. George J Watase
  4. Natalie Warsinger-Pepe
  5. Yukiko M Yamashita
(2018)
Transgenerational dynamics of rDNA copy number in Drosophila male germline stem cells
eLife 7:e32421.
https://doi.org/10.7554/eLife.32421

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