Csm4, in collaboration with Ndj1, mediates telomere-led chromosome dynamics and recombination during yeast meiosis

PLoS Genet. 2008 Sep 26;4(9):e1000188. doi: 10.1371/journal.pgen.1000188.

Abstract

Chromosome movements are a general feature of mid-prophase of meiosis. In budding yeast, meiotic chromosomes exhibit dynamic movements, led by nuclear envelope (NE)-associated telomeres, throughout the zygotene and pachytene stages. Zygotene motion underlies the global tendency for colocalization of NE-associated chromosome ends in a "bouquet." In this study, we identify Csm4 as a new molecular participant in these processes and show that, unlike the two previously identified components, Ndj1 and Mps3, Csm4 is not required for meiosis-specific telomere/NE association. Instead, it acts to couple telomere/NE ensembles to a force generation mechanism. Mutants lacking Csm4 and/or Ndj1 display the following closely related phenotypes: (i) elevated crossover (CO) frequencies and decreased CO interference without abrogation of normal pathways; (ii) delayed progression of recombination, and recombination-coupled chromosome morphogenesis, with resulting delays in the MI division; and (iii) nondisjunction of homologs at the MI division for some reason other than absence of (the obligatory) CO(s). The recombination effects are discussed in the context of a model where the underlying defect is chromosome movement, the absence of which results in persistence of inappropriate chromosome relationships that, in turn, results in the observed mutant phenotypes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Chromosome Segregation
  • Chromosomes, Fungal / genetics*
  • Crosses, Genetic
  • Meiosis*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Nuclear Envelope / genetics
  • Nuclear Envelope / metabolism
  • Recombination, Genetic*
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Telomere / genetics*
  • Telomere / metabolism
  • Telomere-Binding Proteins / genetics
  • Telomere-Binding Proteins / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism

Substances

  • CSM4 protein, S cerevisiae
  • Cell Cycle Proteins
  • Membrane Proteins
  • Ndj1 protein, S cerevisiae
  • RAP1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Telomere-Binding Proteins
  • Transcription Factors