Mutations in the Hco-mptl-1 gene in a field-derived monepantel-resistant isolate of Haemonchus contortus

We examined the receptor gene, Hco-mptl-1, in a highly Zolvix®-resistant and a -susceptible isolate of the parasitic nematode Haemonchus contortus. cDNA coding for the full length receptor protein (Hco-MPTL-1) was present in all clones prepared from a pool of susceptible larvae (21/21 clones) and approximately 50% of those from the resistant isolate (17/33). On the other hand, the remaining clones from the resistant isolate showed various mutations that resulted in truncated predicted proteins, missing at least one transmembrane domain. The most common mutation (11/33 clones) resulted in the retention of intron 15, a premature stop codon, and a truncated protein. Sequencing of intron 15 genomic DNA showed very few SNPs in susceptible larvae and in 12/18 clones from resistant larvae, alongside the presence of at least 17 SNPs in the remaining resistant clones. The present study shows that the highly resistant isolate has a number of mutations in the drug target gene that would most-likely result in a non-functional receptor, thus rendering the larvae insensitive to the drug. The presence of many wild-type sequences in this highly-resistant population suggests that there was a significant presence of heterozygotes in the survivors of the field drench treatment from which the isolate was derived, and hence that at least some of the mutations may be dominant. Alternatively, their presence may be due to the additional influence of mutations at another locus contributing to the...
Source: International Journal for Parasitology: Drugs and Drug Resistance - Category: Parasitology Source Type: research

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ConclusionsFour subtypes (STs) of Blastocystis in human was identified in our study and subtype 3 was the most prevalent subtype. The common subtype (ST3) in this study was identical to the reports from other regions of Iran. For identification of the more subtypes of Blastocystis, comprehensive molecular studies with a large number of Blastocystis isolates are suggested.
Source: Clinical Epidemiology and Global Health - Category: Epidemiology Source Type: research
ConclusionsThe first study of its kind in Australia found T. gondii infection to be highly prevalent. Toxoplasma gondii infection has been neglected in Australian notifiable disease programs therefore Australian public health authorities should focus on improving education to raise awareness and commence longitudinal epidemiological data collection to supplement public health models targeting T. gondii transmission control.
Source: Clinical Epidemiology and Global Health - Category: Epidemiology Source Type: research
(eLife) Malaria parasites can sense a molecule produced by approaching immune cells and then use it to protect themselves from destruction, according to new findings published today in eLife.
Source: EurekAlert! - Infectious and Emerging Diseases - Category: Infectious Diseases Source Type: news
Contributors : Carlos Cordon-Obras ; Anna Barcons-Simon ; Christine Scheidig-Benatar ; Aurelie Cla ës ; Florent Dingli ; Damarys Loew ; Artur ScherfSeries Type : Genome binding/occupancy profiling by high throughput sequencingOrganism : Plasmodium falciparumHeterochromatin is essential in all eukaryotic systems to maintain genome integrity, long-term gene repression and to help chromosome segregation during mitosis. However, heterochromatin regions must be isolated to avoid its spreading over actively transcribed loci. Such function is accomplished by chromatin boundaries, DNA elements that block heterochromatin self-...
Source: GEO: Gene Expression Omnibus - Category: Genetics & Stem Cells Tags: Genome binding/occupancy profiling by high throughput sequencing Plasmodium falciparum Source Type: research
In malaria, rosetting is described as a phenomenon where an infected erythrocyte (IRBC) is attached to uninfected erythrocytes (URBC). In some studies, rosetting has been associated with malaria pathogenesis. Here, we have identified a new type of rosetting. Using a step-by-step approach, we identified IGFBP7, a protein secreted by monocytes in response to parasite stimulation, as a rosette-stimulator forPlasmodium falciparum- andP. vivax-IRBC. IGFBP7-mediated rosette-stimulation was rapid yet reversible. Unlike type I rosetting that involves direct interaction of rosetting ligands on IRBC and receptors on URBC, The IGFBP7...
Source: eLife - Category: Biomedical Science Tags: Immunology and Inflammation Microbiology and Infectious Disease Source Type: research
Infection by the parasite Toxoplasma, which affects about 33% of world population, is associated with an increased risk of several mental health disorders, the most strongly with schizophrenia. It is unknown whether schizophrenia is associated with this infection the most strongly, or whether this association has just been the most intensively studied for historical reasons. We used the data from 6,367 subjects tested for toxoplasmosis who took part in an internet survey to search for associations of these infections with 24 mental health disorders and evidence of otherwise impaired mental health. The typical symptom assoc...
Source: Frontiers in Psychiatry - Category: Psychiatry Source Type: research
mans Roelants A wide range of frogs produce skin poisons composed of bioactive peptides for defence against pathogens, parasites and predators. While several frog families have been thoroughly screened for skin-secreted peptides, others, like the Microhylidae, have remained mostly unexplored. Previous studies of microhylids found no evidence of peptide secretion, suggesting that this defence adaptation was evolutionarily lost. We conducted transcriptome analyses of the skins of Phrynomantis bifasciatus and Phrynomantis microps, two African microhylid species long suspected to be poisonous. Our analyses reveal 17 evo...
Source: Molecules - Category: Chemistry Authors: Tags: Article Source Type: research
an Bishop In this era of precision medicine, insights into the resistance mechanism of drugs are integral for the development of potent therapeutics. Here, we sought to understand the contribution of four point mutations (N51I, C59R, S108N, and I164L) within the active site of the malaria parasite enzyme dihydrofolate reductase (DHFR) towards the resistance of the antimalarial drug pyrimethamine. Homology modeling was used to obtain full-length models of wild type (WT) and mutant DHFR. Molecular docking was employed to dock pyrimethamine onto the generated structures. Subsequent all-atom molecular dynamics (MD) simulat...
Source: Molecules - Category: Chemistry Authors: Tags: Article Source Type: research
The parasitic worms, Schistosoma mansoni and Schistosoma japonicum, reside in the mesenteric veins, where they release eggs that induce a dramatic granulomatous response in the liver and intestines. Subsequently, infection may further develop into significant fibrosis and portal hypertension. Over the past several years, uncovering the mechanism of immunopathology in schistosomiasis has become a major research objective. It is known that T lymphocytes, especially CD4+ T cells, are essential for immune responses against Schistosoma species. However, obtaining a clear understanding of how T lymphocytes regulate the pathologi...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
Plants and fungi are closely associated through parasitic or symbiotic relationships in which bidirectional exchanges of cellular contents occur. Recently, a plant virus was shown to be transmitted from a plant to a fungus, but it is unknown whether fungal viruses can also cross host barriers and spread to plants....
Source: Proceedings of the National Academy of Sciences - Category: Science Authors: Tags: Biological Sciences Source Type: research
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