Evidence map›Paper›PMID 24533276›Full record

ArticleInternational journal for parasitology. Drugs and drug resistance2012

Teladorsagia circumcincta: Molecular characterisation of the avr-14B subunit and its relatively minor role in ivermectin resistance.

María Martínez-Valladares, Peter Geldhof, Nicholas Jonsson, Francisco A Rojo-Vázquez, Philip Skuce

Open access · goldAbstract read
In one paragraph

Article in International journal for parasitology. Drugs and drug resistance, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
1.2field-weighted citation impact, top 18% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed, 9 citations in OpenAlex.

  1. Article
  2. Article
  3. Review
  4. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors at 4 institutions in 3 countries.

María Martínez-ValladaresInstituto de Ganadería de Montana (CSIC-ULE), Finca de Marzanas, 24346 Grulleros, León, Spain.
Peter GeldhofDepartment of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
Nicholas JonssonSchool of Veterinary Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, 464 Bearsden Road, Glasgow G61 1QH, UK.
Francisco A Rojo-VázquezInstituto de Ganadería de Montana (CSIC-ULE), Finca de Marzanas, 24346 Grulleros, León, Spain ; Faculty of Veterinary Medicine, University of León, Campus de Vegazana, 24071 León, Spain.
Philip SkuceMoredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh EH26 0PZ, UK.
Instituto de Ganadería de Montaña · ESGhent University · BEMoredun Research Institute · GBUniversity of Glasgow · GB

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Individual mutations (e.g. L256F) and polymorphisms in the avr-14B gene, a glutamate-gated chloride channel subunit, have been associated with ivermectin (IVM) resistance in Caenorhabditis elegans and Cooperia oncophora. The aim of the present study was to determine the full-length coding sequence of the avr-14B subunit homologue in Teladorsagia circumcincta and determine the presence/absence of the putative L256F SNP or any other potential SNPs of interest. Subsequently, we investigated sequence polymorphisms and transcription patterns between four different T. circumcincta isolates: two from Scotland (MTci1 susceptible and MTci5 triple resistant to benzimidazoles, levamisole and IVM) and two from Spain (S-Sp susceptible and R-Sp double resistant to levamisole and IVM). The complete amino acid sequence of the T. circumcincta avr-14B subunit comprises 438 amino acids. Pyrosequencing analysis failed to detect the presence of the L256F mutation in any of the MTci5 or Sp-R samples tested. However, we revealed significant allele frequency changes by means of SSCP analysis of a 106 bp region encompassing the L256F SNP. Allele E showed the greatest change, following IVM exposure in vitro and in vivo, although sequence analysis did not reveal any coding changes. Sequence analysis of the full-length avr-14B coding sequence showed that two SNPs exclusively found in the resistant strain McTi5 (I270F and T305A) are situated in codons involved in the interaction of the receptor with IVM. Moreover, other potentially significant SNPs (K361E and L364M) were identified between transmembrane regions 3 and 4. However, due to the low frequency of all these SNPs, we cannot conclude they confer IVM resistance in T. circumcincta. Moreover, a modest increase in expression of the avr-14B in both resistant isolates has been shown although these differences were not sufficiently great to consider avr-14B to be the sole or even a major determinant of IVM resistance in this species.

Indexed as

Anthelmintic resistanceGluCl channelsIvermectinSheepTeladorsagia circumcincta

Identifiers

PMID24533276
PMCPMC3862489
OpenAlexW1998696021

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.