Molecular cloning and genetic characterization of the Saccharomyces cerevisiae NGS1/MRE11 gene

Curr Genet. 1998 Dec;34(5):368-74. doi: 10.1007/s002940050408.

Abstract

The Saccharomyces cerevisiae ngs1-1 mutant was previously identified by its enhanced sensitivity to simple DNA-alkylating agents such as methyl methanesulfonate but not to UV. Molecular cloning and sequencing of NGS1 as a putative DNA-alkylation repair gene revealed that it isidentical to MRE11, a gene that is involved in DNA recombinational repair. In order to investigate functional domains of the Mre11 protein, nucleotide-sequence alterations of a number of mre11 mutant alleles, including ngs1-1, mre11-1 (ts), mre11-2, mre11-3 and mre11-58, were determined. Most of these mutations map to the N-terminus ofMre11, emphasizing the importance of this highly conserved domain. The ngs1-1 and mre11-3 mutants carry nonsense mutations resulting in truncated proteins. Missense mutations were found in mre11-1 (ts), mre11-2 and mre11-58, of which mre11-2 and mre11-58 mapped to the conserved phosphoesterase domains, indicating the involvement of these motifs in the formation and/or processing of DNA double-strand breaks. Finally, mitotic-recombination assays show that the mre11 delta mutation enhances inter-chromosomal recombination but decreases the intra-chromosomal deletion frequency. In addition, MRE11 appears to play different roles during spontaneous and alkylation-induced homologous mitotic recombination.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Alkylating / adverse effects
  • Chromosomes, Fungal / drug effects
  • Chromosomes, Fungal / genetics
  • Cloning, Molecular
  • DNA / genetics
  • DNA / metabolism
  • DNA Repair / genetics
  • Endodeoxyribonucleases*
  • Exodeoxyribonucleases*
  • Fungal Proteins / genetics*
  • Genes, Fungal / genetics*
  • Methyl Methanesulfonate / adverse effects
  • Mutation
  • Recombination, Genetic / drug effects
  • Repetitive Sequences, Nucleic Acid
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins*

Substances

  • Antineoplastic Agents, Alkylating
  • Fungal Proteins
  • Saccharomyces cerevisiae Proteins
  • DNA
  • Methyl Methanesulfonate
  • Endodeoxyribonucleases
  • Exodeoxyribonucleases
  • MRE11 protein, S cerevisiae