Cohesin SMC1 beta is required for meiotic chromosome dynamics, sister chromatid cohesion and DNA recombination

Nat Cell Biol. 2004 Jun;6(6):555-62. doi: 10.1038/ncb1135. Epub 2004 May 16.


Sister chromatid cohesion ensures the faithful segregation of chromosomes in mitosis and in both meiotic divisions. Meiosis-specific components of the cohesin complex, including the recently described SMC1 isoform SMC1 beta, were suggested to be required for meiotic sister chromatid cohesion and DNA recombination. Here we show that SMC1 beta-deficient mice of both sexes are sterile. Male meiosis is blocked in pachytene; female meiosis is highly error-prone but continues until metaphase II. Prophase axial elements (AEs) are markedly shortened, chromatin extends further from the AEs, chromosome synapsis is incomplete, and sister chromatid cohesion in chromosome arms and at centromeres is lost prematurely. In addition, crossover-associated recombination foci are absent or reduced, and meiosis-specific perinuclear telomere arrangements are impaired. Thus, SMC1 beta has a key role in meiotic cohesion, the assembly of AEs, synapsis, recombination, and chromosome movements.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Centromere / genetics
  • Chromatids / genetics*
  • Chromosomal Proteins, Non-Histone
  • Chromosome Pairing / genetics
  • Chromosome Segregation / genetics
  • Cohesins
  • DNA / genetics
  • Female
  • Fungal Proteins
  • Infertility / genetics*
  • Male
  • Meiosis / genetics*
  • Metaphase / genetics
  • Mice
  • Mice, Knockout
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Oogenesis / genetics
  • Recombination, Genetic / genetics*
  • Spermatogenesis / genetics
  • Telomere / genetics


  • Cell Cycle Proteins
  • Chromosomal Proteins, Non-Histone
  • Fungal Proteins
  • Nuclear Proteins
  • Smc1l2 protein, mouse
  • DNA