title: Differential expression of liver fluke β-tubulin isotypes at selected life cycle stages.
abstract: We have shown that Fasciola hepatica expresses at least six β-tubulins in the adult stage of its life cycle, designated F.hep-β-tub1-6 (Ryan et al., 2008). Here we show that different complements of tubulin isotypes are expressed in different tissues and at different life cycle stages; this information may inform the search for novel anthelmintics. The predominant (as judged by quantitative PCR) isotype transcribed at the adult stage was F.hep-β-tub1 and immunolocalisation studies revealed that this isotype occurred mainly in mature spermatozoa and vitelline follicles. Quantitative PCR indicated that changes occurred in the transcription levels of β-tubulin isotypes at certain life cycle stages and may be of importance in the efficacy of benzimidazole-based anthelmintic drugs, but there were no significant differences between the triclabendazole-susceptible Leon isolate and the triclabendazole-resistant Oberon isolate in the transcription levels of each of the isotypes. When three well-characterised isolates with differing susceptibilities to triclabendazole were compared, only one amino acid change resulting from a homozygous coding sequence difference (Gly269Ser) in isotype 4 was observed. However, this change was not predicted to alter the overall structure of the protein. In conclusion, these findings indicate that there is tissue-specific expression of tubulin isotypes in the liver fluke but the development of resistance to triclabendazole is not associated with changes in its presumed target molecule.
authors.affiliation: School of Biological Sciences, The Queen's University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
authors.forename: Marc-Aurel
authors.initials: MA
authors.lastname: Fuchs
authors.forename: Louise A
authors.initials: LA
authors.lastname: Ryan
authors.forename: Emma L
authors.initials: EL
authors.lastname: Chambers
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Moore
authors.forename: Ian
authors.initials: I
authors.lastname: Fairweather
authors.forename: Alan
authors.initials: A
authors.lastname: Trudgett
authors.forename: David J
authors.initials: DJ
authors.lastname: Timson
authors.forename: Gerry P
authors.initials: GP
authors.lastname: Brennan
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Hoey
mesh_terms: D000818:Animals; D000871:Anthelmintics / Q000494:pharmacology; D001562:Benzimidazoles / Q000494:pharmacology; D004351:Drug Resistance; D005210:Fasciola hepatica / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D008018:Life Cycle Stages; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D014158:Transcription, Genetic; D000077682:Triclabendazole; D014404:Tubulin / Q000096:biosynthesis* / Q000235:genetics*
chemical_list: D000871:Anthelmintics; D001562:Benzimidazoles; D020033:Protein Isoforms; D014404:Tubulin; D000077682:Triclabendazole
keywords: Anthelmintic resistance; Fasciola hepatica; Microtubule; Tubulin isotype