Identification and characterization of SNQ2, a new multidrug ATP binding cassette transporter of the yeast plasma membrane

J Biol Chem. 1995 Jul 28;270(30):18150-7. doi: 10.1074/jbc.270.30.18150.

Abstract

The SNQ2 gene of Saccharomyces cerevisiae, which encodes an ATP binding cassette protein responsible for resistance to the mutagen 4-nitroquinoline oxide, is regulated by the DNA-binding proteins PDR1 and PDR3. In a plasma membrane-enriched fraction from a pdr1 mutant, the SNQ2 protein is found in the 160-kDa over-expressed band, together with PDR5. The SNQ2 protein was solubilized with n-dodecyl beta-D-maltoside from the plasma membranes of a PDR5-deleted strain and separated from the PMA1 H(+/-)ATPase by sucrose gradient centrifugation. The enzyme shows a nucleoside triphosphatase activity that differs biochemically from that of PDR5 (Decottignies, A., Kolaczkowski, M., Balzi, E., and Goffeau, A. (1994) J. Biol. Chem. 269, 12797-12803) and is sensitive to vanadate, erythrosine B, and Triton X-100 but not to oligomycin, which inhibits the PDR5 activity only. Disruption of both PDR5 and SNQ2 in a pdr1 mutant decreases the cell growth rate and reveals the presence of at least two other ATP binding cassette proteins in the 160-kDa overexpressed band that have been identified by amino-terminal microsequencing.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • ATP-Binding Cassette Transporters / chemistry
  • ATP-Binding Cassette Transporters / genetics
  • ATP-Binding Cassette Transporters / metabolism*
  • Base Sequence
  • Carrier Proteins / antagonists & inhibitors
  • Carrier Proteins / isolation & purification
  • Carrier Proteins / metabolism
  • Cell Division / genetics
  • Cell Membrane / metabolism
  • DNA Primers
  • DNA-Binding Proteins / metabolism
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics
  • Fungal Proteins / isolation & purification
  • Fungal Proteins / metabolism*
  • Hydrolysis
  • Membrane Proteins / antagonists & inhibitors
  • Membrane Proteins / isolation & purification
  • Membrane Proteins / metabolism
  • Molecular Sequence Data
  • Pyrophosphatases / metabolism
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins*
  • Transcription, Genetic

Substances

  • ATP-Binding Cassette Transporters
  • Carrier Proteins
  • DNA Primers
  • DNA-Binding Proteins
  • Fungal Proteins
  • Membrane Proteins
  • PDR5 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Pyrophosphatases
  • uridine triphosphatase