title: An amino acid substitution in Fasciola hepatica P-glycoprotein from triclabendazole-resistant and triclabendazole-susceptible populations.
abstract: Control of fasciolosis is threatened by the development of anthelmintic resistance. Enhanced triclabendazole (TCBZ) efflux by ABC transporters such as P-glycoprotein (Pgp) has been implicated in this process. A putative full length cDNA coding for a Pgp expressed in adult Fasciola hepatica has been constructed and used to design a primer set capable of amplifying a region encoding part of the second nucleotide binding domain of Pgp when genomic DNA was used as a template. Application of this primer set to genomic DNA from TCBZ-resistant and -susceptible field populations has shown a significant difference in the alleles present. Analysis of an allele occurring at a three-fold higher frequency in the "resistant" population revealed that it was characterised by a serine to arginine substitution at residue 1144. Homology modelling studies have been used to locate this site in the Pgp structure and hence assess its potential to modify functional activity.
authors.affiliation: School of Biological Sciences, The Queen's University of Belfast, 97, Lisburn Road, Belfast BT9 7BL, N. Ireland, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Wilkinson
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Law
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Hoey
authors.forename: Ian
authors.initials: I
authors.lastname: Fairweather
authors.forename: Gerard P
authors.initials: GP
authors.lastname: Brennan
authors.forename: Alan
authors.initials: A
authors.lastname: Trudgett
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000483:Alleles; D019943:Amino Acid Substitution; D000818:Animals; D000871:Anthelmintics / Q000494:pharmacology*; D001562:Benzimidazoles / Q000494:pharmacology*; D017931:DNA Primers / Q000235:genetics; D004351:Drug Resistance; D005210:Fasciola hepatica / Q000187:drug effects* / Q000235:genetics*; D008958:Models, Molecular; D016133:Polymerase Chain Reaction; D011487:Protein Conformation; D000077682:Triclabendazole
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000871:Anthelmintics; D001562:Benzimidazoles; D017931:DNA Primers; D000077682:Triclabendazole