Gene SNQ2 of Saccharomyces cerevisiae, which confers resistance to 4-nitroquinoline-N-oxide and other chemicals, encodes a 169 kDa protein homologous to ATP-dependent permeases

Mol Gen Genet. 1993 Jan;236(2-3):214-8. doi: 10.1007/BF00277115.


The yeast gene SNQ2 confers hyper-resistance to the mutagens 4-nitroquinoline-N-oxide (4-NQO) and Triaziquone, as well as to the chemicals sulphomethuron methyl and phenanthroline when present in multiple copies in transformants of Saccharomyces cerevisiae. Subcloning and sequencing of a 5.5 kb yeast DNA fragment revealed that SNQ2 has an open reading frame of 4.5 kb. The putative encoded polypeptide of 1501 amino acids has a predicted molecular weight of 169 kDa and has several hydrophobic regions. Northern analysis showed a transcript of 5.5 kb. Haploid cells with a disrupted SNQ2 reading frame are viable. The SNQ2-encoded protein has domains believed to be involved in ATP binding and is likely to be membrane associated. It most probably serves as an ATP-dependent permease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 4-Nitroquinoline-1-oxide / pharmacology*
  • ATP-Binding Cassette Transporters / genetics*
  • Adenosine Triphosphate / pharmacology*
  • Amino Acid Sequence
  • Cloning, Molecular
  • Drug Resistance, Microbial
  • Genes, Fungal / genetics*
  • Membrane Transport Proteins / drug effects
  • Membrane Transport Proteins / genetics*
  • Molecular Sequence Data
  • Protein Conformation
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins*
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Solubility
  • Transformation, Genetic


  • ATP-Binding Cassette Transporters
  • Membrane Transport Proteins
  • SNQ2 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • 4-Nitroquinoline-1-oxide
  • Adenosine Triphosphate