Molecular and General Genetics MGG

, Volume 227, Issue 2, pp 260–266

Molecular cloning of a glutathione S-transferase overproduced in an insecticide-resistant strain of the housefly (Musca domestica)

  • Jian-ying Wang
  • Steve McCommas
  • Michael Syvanen
Article

DOI: 10.1007/BF00259679

Cite this article as:
Wang, J., McCommas, S. & Syvanen, M. Molec. Gen. Genet. (1991) 227: 260. doi:10.1007/BF00259679

Summary

We report the cloning and sequencing of a glutathione S-transferase (GST) gene from the housefly Musca domestica. A cDNA λgt11 library was prepared from the organophosphate insecticide-resistant housefly strain Cornell-R — a variant that has elevated GST activity. The λ phage GST clone was identified on the basis of its ability to cross-hybridize to a GST DNA probe from Drosophila melanogaster. Based on amino acid homology to other GSTs and expression of GST activity in Escherichia coli, the Musca GST gene (MdGST-1) belongs to the GST gene family. Although organophosphate resistance in Cornell-R is largely due to one of the GSTs, MdGST-1 is probably not the enzyme responsible for resistance. The mutation that controls resistance to organophosphate insecticides in Cornell-R is highly unstable and we isolated spontaneous variants to both insecticide sensitivity and to even higher levels of resistance. This provided us with an isogenic set of three strains. We found that MdGST-1 transcript levels as measured by Northern assays are higher in all three Cornell-R strains relative to the sensitive wild type, but that the sensitive Cornell-R strain has more MdGST-1 transcript than does the highly resistant Cornell-R strain. These data as well as Southern analysis of genomic DNA allow us to conclude: (1) there are multiple GST genes in M. domestica; (2) the natural variant Cornell-R excess transcript from two and probably more of these genes; and (3) the unstable mutation in Cornell-R influences the levels of multiple GSTs.

Key words

Glutathione S-transferaseMusca domesticacDNA sequenceOrganophosphate triestersInsecticide resistance

Copyright information

© Springer-Verlag 1991

Authors and Affiliations

  • Jian-ying Wang
    • 1
  • Steve McCommas
    • 2
  • Michael Syvanen
    • 1
  1. 1.Department of Medical Microbiology and Immunology, School of MedicineUniversity of CaliforniaDavisUSA
  2. 2.Department of Biological SciencesUniversity of Southern IllinoisEdwardsvilleUSA