Synaptonemal complex assembly in C. elegans is dispensable for loading strand-exchange proteins but critical for proper completion of recombination

Dev Cell. 2003 Sep;5(3):463-74. doi: 10.1016/s1534-5807(03)00232-6.


Here we probe the relationships between assembly of the synaptonemal complex (SC) and progression of recombination between homologous chromosomes during Caenorhabditis elegans meiosis. We identify SYP-2 as a structural component of the SC central region and show that central region assembly depends on proper morphogenesis of chromosome axes. We find that the SC central region is dispensable for initiation of recombination and for loading of DNA strand-exchange protein RAD-51, despite the fact that extensive RAD-51 loading normally occurs in the context of assembled SC. Further, persistence of RAD-51 foci and absence of crossover products in meiotic mutants suggests that SC central region components and recombination proteins MSH-4 and MSH-5 are required to promote conversion of resected double-strand breaks into stable post-strand exchange intermediates. Our data also suggest that early prophase barriers to utilization of sister chromatids as repair templates do not depend on central region assembly.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans
  • Caenorhabditis elegans Proteins / isolation & purification
  • Caenorhabditis elegans Proteins / metabolism
  • Caenorhabditis elegans Proteins / physiology*
  • Chromosome Pairing
  • Chromosomes / metabolism
  • Crossing Over, Genetic
  • DNA Damage / genetics
  • DNA-Binding Proteins / metabolism
  • Endodeoxyribonucleases
  • Esterases / metabolism
  • Immunohistochemistry
  • Indoles / metabolism
  • Meiosis*
  • Molecular Sequence Data
  • Mutation
  • Nerve Tissue Proteins / isolation & purification
  • Nerve Tissue Proteins / physiology*
  • RNA, Small Interfering / metabolism
  • Rad51 Recombinase
  • Recombination, Genetic / physiology*
  • Saccharomyces cerevisiae Proteins / metabolism
  • Sequence Alignment
  • Synaptonemal Complex / metabolism*
  • Synaptonemal Complex / ultrastructure
  • Time Factors


  • Caenorhabditis elegans Proteins
  • DNA-Binding Proteins
  • Indoles
  • MSH4 protein, S cerevisiae
  • MSH5 protein, S cerevisiae
  • Nerve Tissue Proteins
  • RNA, Small Interfering
  • SYP-2 protein, C elegans
  • Saccharomyces cerevisiae Proteins
  • DAPI
  • Rad51 Recombinase
  • rad-51 protein, C elegans
  • Endodeoxyribonucleases
  • Esterases
  • meiotic recombination protein SPO11