Pat1: a topoisomerase II-associated protein required for faithful chromosome transmission in Saccharomyces cerevisiae

Nucleic Acids Res. 1996 Dec 1;24(23):4791-7. doi: 10.1093/nar/24.23.4791.


Saccharomyces cerevisiae top2 mutants deficient in topoisomerase II activity are defective in chromosome segregation during both mitotic and meiotic cell divisions. To identify proteins that act in concert with topoisomerase II during chromosome segregation in S.cerevisiae, we have used a two-hybrid cloning approach. We report the isolation of the PAT1 gene (for protein associated with topoisomerase II), which encodes a novel 90 kDa proline- and glutamine-rich protein that interacts with a highly conserved, leucine-rich region of topoisomerase II in vivo. Strains lacking Pat1p exhibit a slow growth rate and a phenotype reminiscent of conditional top2 mutants grown at the semi-permissive temperature; most notably, a reduced fidelity of chromosome segregation during both mitosis and meiosis. These findings indicate that the PAT1 gene is necessary for accurate chromosome transmission during cell division in eukaryotic cells and suggest that the interaction of Pat1p and topoisomerase II is an important component of this function.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Binding Sites
  • Cell Division
  • Chromosomes, Fungal / genetics*
  • Cloning, Molecular
  • DNA Topoisomerases, Type II / chemistry
  • DNA Topoisomerases, Type II / genetics
  • DNA Topoisomerases, Type II / metabolism*
  • DNA, Fungal / chemistry
  • DNA, Fungal / genetics
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Gene Deletion
  • Gene Expression
  • Leucine
  • Meiosis
  • Mitosis
  • Mutation
  • Phenotype
  • RNA-Binding Proteins
  • Recombinant Proteins
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae Proteins*


  • DNA, Fungal
  • DNA-Binding Proteins
  • PAT1 protein, S cerevisiae
  • RNA-Binding Proteins
  • Recombinant Proteins
  • Saccharomyces cerevisiae Proteins
  • DNA Topoisomerases, Type II
  • Leucine