Molecular cloning of a phospholipid-hydroperoxide glutathione peroxidase gene from the tick, Boophilus microplus (Acari: Ixodidae)

  • Cossío-Bayúgar R
  • Miranda E
  • Holman P
 et al. 
  • 1


    Mendeley users who have this article in their library.
  • N/A


    Citations of this article.


Phospholipid-hydroperoxide glutathione peroxidase (PHGPx) enzymes are associated with cellular protection by the role they play in reducing hydroperoxides of phospholipids, thereby preventing membrane lipoperoxidation. As part of their toxic effect, some pesticides stimulate peroxidation of cellular membranes. We isolated and sequenced a PHGPx gene from the cattle tick Boophilus microplus that encodes a protein of 169 amino acids, including a TGA-encoded selenocysteine at residue 46 and active site residues Gln(82) and Trp(135) that interact with the selenocysteine. The motif that directs the insertion of selenocysteine at the opal codon is found in the 3'-untranslated region. PHGPx sequences from pesticide-resistant and susceptible B. microplus ticks show nucleotide differences at eight positions among the strains, with five resulting in amino acid substitutions in the deduced protein sequence. Two distinct PHGPx alleles were identified in an organophosphate-resistant tick strain. Real-time PCR quantification of gene expression revealed increased PHGPx in two strains resistant to a single acaricide class. Strains resistant to two or more classes showed a reduction in PHGPx.

Author-supplied keywords

  • 3' Untranslated Regions/genetics
  • Amino Acid
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Boophilus microplus
  • Cattle
  • Cloning
  • Complementary/genetics
  • Conserved Sequence
  • DNA
  • DNA Primers
  • Glutathione Peroxidase/chemistry/*genetics
  • Humans
  • Insect Proteins/*genetics
  • Insecticides/pharmacology
  • Larva
  • Molecular
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Phospholipid-hydroperoxide glutathione peroxidase
  • Pyrethrins/pharmacology
  • SECIS region
  • Selenocysteine
  • Sequence Alignment
  • Sequence Homology
  • Ticks/enzymology/*genetics
  • cDNA

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in


  • Raquel Cossío-Bayúgar

  • Estefan Miranda

  • Patricia J. Holman

  • R Cossio-Bayugar

  • Estefan Miranda

  • Patricia J. Holman

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free