Bqt2p is essential for initiating telomere clustering upon pheromone sensing in fission yeast

J Cell Biol. 2006 Jun 19;173(6):845-51. doi: 10.1083/jcb.200602152. Epub 2006 Jun 12.

Abstract

The telomere bouquet, i.e., telomere clustering on the nuclear envelope (NE) during meiotic prophase, is thought to promote homologous chromosome pairing. Using a visual screen, we identified bqt2/im295, a mutant that disrupts telomere clustering in fission yeast. Bqt2p is required for linking telomeres to the meiotic spindle pole body (SPB) but not for attachment of telomeres or the SPB to the NE. Bqt2p is expressed upon pheromone sensing and colocalizes thereafter to Sad1p, an SPB protein. This localization only depends on Bqt1p, not on other identified proteins required for telomere clustering. Upon pheromone sensing, generation of Sad1p foci next to telomeres depends on Bqt2p. However, depletion of Bqt2p from the SPB is dispensable for dissolving the telomere bouquet at the end of meiotic prophase. Therefore, telomere bouquet formation requires Bqt2p as a linking component and is finely regulated during meiotic progression.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Heterochromatin / metabolism
  • Mutation
  • Pheromones / metabolism*
  • Prophase
  • Schizosaccharomyces / metabolism*
  • Schizosaccharomyces pombe Proteins / genetics
  • Schizosaccharomyces pombe Proteins / metabolism
  • Schizosaccharomyces pombe Proteins / physiology*
  • Shelterin Complex
  • Spindle Apparatus / metabolism
  • Telomere / metabolism*
  • Telomere-Binding Proteins / genetics
  • Telomere-Binding Proteins / physiology*

Substances

  • Bqt2 protein, S pombe
  • Heterochromatin
  • KMS1 protein, S pombe
  • Pheromones
  • Rap1 protein, S pombe
  • SAD1 protein, S pombe
  • Schizosaccharomyces pombe Proteins
  • Shelterin Complex
  • Telomere-Binding Proteins