1. Cell Biology
  2. Chromosomes and Gene Expression
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The asymmetry of female meiosis reduces the frequency of inheritance of unpaired chromosomes

  1. Daniel B Cortes
  2. Karen L McNally
  3. Paul E Mains
  4. Francis J McNally  Is a corresponding author
  1. University of California, Davis, United States
  2. University of Calgary, Canada
Research Article
  • Cited 17
  • Views 2,866
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Cite this article as: eLife 2015;4:e06056 doi: 10.7554/eLife.06056

Abstract

Trisomy, the presence of a third copy of one chromosome, is deleterious and results in inviable or defective progeny if passed through the germ line. Random segregation of an extra chromosome is predicted to result in a high frequency of trisomic offspring from a trisomic parent. C. elegans with trisomy of the X chromosome, however, have far fewer trisomic offspring than expected. We found that the extra X chromosome was preferentially eliminated during anaphase I of female meiosis. We utilized a mutant with a specific defect in pairing of the X chromosome as a model to investigate the apparent bias against univalent inheritance. First, univalents lagged during anaphase I and their movement was biased toward the cortex and future polar body. Second, late-lagging univalents were frequently captured by the ingressing polar body contractile ring. The asymmetry of female meiosis can thus partially correct pre-existing trisomy.

Article and author information

Author details

  1. Daniel B Cortes

    Department of Molecular and Cellular Biology, University of California, Davis, Davis, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Karen L McNally

    Department of Molecular and Cellular Biology, University of California, Davis, Davis, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Paul E Mains

    Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Francis J McNally

    Department of Molecular and Cellular Biology, University of California, Davis, Davis, United States
    For correspondence
    fjmcnally@ucdavis.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Anthony A Hyman, Max Planck Institute of Molecular Cell Biology and Genetics, Germany

Publication history

  1. Received: December 12, 2014
  2. Accepted: April 3, 2015
  3. Accepted Manuscript published: April 7, 2015 (version 1)
  4. Version of Record published: April 29, 2015 (version 2)

Copyright

© 2015, Cortes 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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