The Neurospora crassa mus-19 gene is identical to the qde-3 gene, which encodes a RecQ homologue and is involved in recombination repair and postreplication repair

Curr Genet. 2004 Feb;45(1):37-44. doi: 10.1007/s00294-003-0459-3. Epub 2003 Nov 1.


An allele called mus-19 was identified by screening temperature-sensitive and mutagen-sensitive mutants of Neurospora crassa. The mus-19 gene was genetically mapped to a region near the end of the right arm of linkage group I, where a RecQ homologue called qde-3 had been physically mapped in the Neurospora database. Complementation tests between the mus-19 mutant and the qde-3(RIP) mutant showed that mus-19 and qde-3 were the same gene. The qde-3 genes of both mutants were cloned and sequenced; and the results showed that they have mutation(s) in their qde-3 genes. The original mus-19 and qde-3(RIP) mutants are defective in quelling, as reported for other qde-3 mutants. The mutants show high sensitivity to methyl methanesulfonate, ethyl methanesulfonate, N-methyl- N'-nitro- N-nitrosoguanidine, tert-butyl hydroperoxide, 4-nitroquinoline-1-oxide, hydroxyurea and histidine. Epistasis analysis indicated that the qde-3 gene belongs both to the uvs-6 recombination repair pathway and the uvs-2 postreplication repair pathway. The qde-3 mutation has no effect on the integration of a plasmid carrying the mtr gene by homologous recombination. In homozygous crosses, the qde-3 mutant is defective in ascospore production.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / genetics*
  • Chromosome Mapping
  • DNA Damage / drug effects
  • DNA Damage / radiation effects
  • DNA Helicases / chemistry
  • DNA Helicases / genetics*
  • DNA Repair*
  • DNA Replication
  • DNA, Fungal / genetics
  • Epistasis, Genetic
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics*
  • Genes, Fungal / genetics*
  • Mutagens / pharmacology
  • Neurospora crassa / drug effects
  • Neurospora crassa / enzymology
  • Neurospora crassa / genetics*
  • Neurospora crassa / radiation effects
  • RecQ Helicases
  • Recombination, Genetic*
  • Temperature
  • Ultraviolet Rays


  • DNA, Fungal
  • Fungal Proteins
  • Mutagens
  • Adenosine Triphosphatases
  • DNA Helicases
  • RecQ Helicases
  • QDE-3 protein, Neurospora crassa