1. Cell Biology
  2. Chromosomes and Gene Expression
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Divergent kleisin subunits of cohesin specify mechanisms to tether and release meiotic chromosomes

  1. Aaron F Severson
  2. Barbara J Meyer  Is a corresponding author
  1. Cleveland State University, United States
  2. Howard Hughes Medical Institute, University of California, Berkeley, United States
Research Article
  • Cited 35
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Cite this article as: eLife 2014;3:e03467 doi: 10.7554/eLife.03467

Abstract

We show that multiple, functionally specialized cohesin complexes mediate the establishment and two-step release of sister chromatid cohesion that underlies the production of haploid gametes. In C. elegans, the meiotic kleisin subunits REC-8 and COH-3/4 endow cohesins with distinctive properties, specifying how cohesins load onto chromosomes and then trigger and release cohesion. Unlike REC-8 cohesin, COH-3/4 cohesin becomes cohesive through a replication-independent mechanism initiated by the DNA double-stranded breaks that induce crossover recombination. Thus, break-induced cohesion also tethers replicated meiotic chromosomes. Later, recombination stimulates separase-independent removal of REC-8 and COH-3/4 cohesins from reciprocal chromosomal territories flanking the crossover site. This region-specific removal likely underlies the two-step separation of homologs and sisters. Unexpectedly, COH-3/4 performs cohesion-independent functions in synaptonemal complex assembly. This new model for cohesin function in reducing genome copy number diverges from that established in yeast but likely applies directly to plants and mammals, which utilize similar meiotic kleisins.

Article and author information

Author details

  1. Aaron F Severson

    Cleveland State University, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Barbara J Meyer

    Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
    For correspondence
    bjmeyer@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Bernard de Massy, Institute of Human Genetics, CNRS UPR 1142, France

Publication history

  1. Received: May 23, 2014
  2. Accepted: August 28, 2014
  3. Accepted Manuscript published: August 29, 2014 (version 1)
  4. Version of Record published: September 25, 2014 (version 2)

Copyright

© 2014, Severson & Meyer

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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