Using Caenorhabditis elegans to produce functional secretory proteins of parasitic nematodes

Treatment of parasitic nematode infections depends primarily on the use of anthelmintics. However, this drug arsenal is limited, and resistance against most anthelmintics is widespread. Emodepside is a new anthelmintic drug effective against gastrointestinal and filarial nematodes. Nematodes that are resistant to other anthelmintic drug classes are susceptible to emodepside, indicating that the emodepside mode of action is distinct from previous anthelmintics. The laboratory-adapted Caenorhabditis elegans strain N2 is sensitive to emodepside, and genetic selection and in vitro experiments implicated slo-1, a BK potassium channel gene, in emodepside mode of action. In an effort to understand how natural populations will respond to emodepside, we measured brood sizes and developmental rates of wild C. elegans strains after exposure to the drug and found natural variation across the species. Some variation in emodepside responses can be explained by natural differences in slo-1. This result suggests that other genes in addition to slo-1 underlie emodepside resistance in wild C. elegans strains. Additionally, all assayed strains have higher offspring production in low concentrations of emodepside (a hormetic effect), which could impact treatment strategies. We find that natural variation affects emodepside sensitivity, supporting the suitability of C. elegans as a model system to study emodepside responses across parasitic nematodes.

Download Full-text

In Vitro Efficacy of Aqueous and Methanol Extract of Cassia siamea Against the Motility of Caenorhabditis elegans

Tropical Life Sciences Research ◽

10.21315/tlsr2020.31.3.10 ◽

2020 ◽

Vol 31 (3) ◽

pp. 145-159

Author(s):

Haladu Ali Gagman ◽

Nik Ahmad Irwan Izzauddin Nik Him ◽

Hamdan Ahmad ◽

Shaida Fariza Sulaiman ◽

Rahmad Zakaria ◽

...

Keyword(s):

Caenorhabditis Elegans ◽

Methanol Extract ◽

Anthelmintic Resistance ◽

Gastrointestinal Nematode ◽

Parasitic Nematodes ◽

Cassia Siamea ◽

Methanol Extracts ◽

C Elegans ◽

Significant Difference

Gastrointestinal nematode infections can cause great losses in revenue due to decrease livestock production and animal death. The use of anthelmintic to control gastrointestinal nematode put a selection pressure on nematode populations which led to emergence of anthelmintic resistance. Because of that, this study was carried out to investigate the efficacy of aqueous and methanol extract of Cassia siamea against the motility of C. elegans Bristol N2 and C. elegans DA1316. Caenorhabditis elegans Bristol N2 is a susceptible strain and C. elegans DA1316 is an ivermectin resistant strain. In vitro bioassay of various concentrations of (0.2, 0.6, 0.8, 1.0 and 2.0 mg mL–1) aqueous and methanol extracts of C. siamea was conducted against the motility of L4 larvae of C. elegans Bristol N2 and C. elegans DA1316. The L4 larvae were treated with 0.02 μg mL–1 of ivermectin served as positive control while those in M9 solution served as negative control. The activity of the extracts was observed after 24 h and 48 h. A significant difference was recorded in the extract performance compared to control at (P < 0.001) after 48 h against the motility of the larvae of both strains. The methanol extracts inhibited the motility of C. elegans Bristol N2 by 86.7% as well as DA1316 up to 84.9% at 2.0 mg mL–1 after 48 h. The methanol extract was more efficient than aqueous extract (P < 0.05) against the motility of both strains of C. elegans. Cassia siamea may be used as a natural source of lead compounds for the development of alternative anthelmintic against parasitic nematodes as well ivermectin resistant strains of nematodes.

Download Full-text

Identification of a putative expansin gene expressed in the subventral glands of the cereal cyst nematode Heterodera avenae

Nematology ◽

10.1163/156854111x614674 ◽

2012 ◽

Vol 14 (5) ◽

pp. 571-577 ◽

Cited By ~ 6

Author(s):

Haibo Long ◽

Deliang Peng ◽

Wenkun Huang ◽

Yanke Liu ◽

Huan Peng

Keyword(s):

Cyst Nematode ◽

Developmental Expression ◽

Heterodera Avenae ◽

Parasitic Nematodes ◽

Secretory Proteins ◽

Expansin Gene ◽

Genes Encoding ◽

Juvenile Stages ◽

Stage Process ◽

Parasitism Genes

Parasitism genes encoding secretory proteins expressed in the pharyngeal glands of plant-parasitic nematodes play important roles in the parasitic process. A new expansin gene (Ha-expb1) expressed in the subventral glands of the sedentary cyst nematode, Heterodera avenae, was cloned. Southern blot analysis suggested that Ha-expb1 is a member of a multigene family. The deduced protein Ha-EXPB1 consists of a signal peptide, a CBM II and an expansin domain, and was significantly similar to expansins and expansin-like proteins from the potato cyst nematode, Globodera rostochiensis, and the pine wood nematodes, Bursaphelenchus spp. In situ hybridisation showed that Ha-expb1 transcript specifically accumulated in the two subventral gland cells of the second-stage juveniles. Developmental expression confirmed that its transcript abundances were high in the motile juvenile stages and low in the sedentary stage of the nematode, implying a role in the early parasitic-stage process, most likely in aiding migration within the plant.

Download Full-text

Expression of nicotinic acetylcholine receptor subunits from parasitic nematodes in Caenorhabditis elegans

Molecular and Biochemical Parasitology ◽

10.1016/j.molbiopara.2015.12.006 ◽

2015 ◽

Vol 204 (1) ◽

pp. 44-50 ◽

Cited By ~ 9

Author(s):

Megan A. Sloan ◽

Barbara J. Reaves ◽

Mary J. Maclean ◽

Bob E. Storey ◽

Adrian J. Wolstenholme

Keyword(s):

Caenorhabditis Elegans ◽

Acetylcholine Receptor ◽

Nicotinic Acetylcholine Receptor ◽

Parasitic Nematodes ◽

Nicotinic Acetylcholine

Download Full-text

An Enterotoxin-Like Binary Protein from Pseudomonas protegens with Potent Nematicidal Activity

Applied and Environmental Microbiology ◽

10.1128/aem.00942-17 ◽

2017 ◽

Vol 83 (19) ◽

Author(s):

Jun-Zhi Wei ◽

Daniel L. Siehl ◽

Zhenglin Hou ◽

Barbara Rosen ◽

Jarred Oral ◽

...

Keyword(s):

Escherichia Coli ◽

Caenorhabditis Elegans ◽

Cholera Toxin ◽

Nematicidal Activity ◽

Binary Toxin ◽

Parasitic Nematodes ◽

Free Living ◽

Subunit A ◽

Content Type ◽

Panagrellus Redivivus

ABSTRACT Soil microbes are a major food source for free-living soil nematodes. It is known that certain soil bacteria have evolved systems to combat predation. We identified the nematode-antagonistic Pseudomonas protegens strain 15G2 from screening of microbes. Through protein purification we identified a binary protein, designated Pp-ANP, which is responsible for the nematicidal activity. This binary protein inhibits Caenorhabditis elegans growth and development by arresting larvae at the L1 stage and killing older-staged worms. The two subunits, Pp-ANP1a and Pp-ANP2a, are active when reconstituted from separate expression in Escherichia coli. The binary toxin also shows strong nematicidal activity against three other free-living nematodes (Pristionchus pacificus, Panagrellus redivivus, and Acrobeloides sp.), but we did not find any activity against insects and fungi under test conditions, indicating specificity for nematodes. Pp-ANP1a has no significant identity to any known proteins, while Pp-ANP2a shows ∼30% identity to E. coli heat-labile enterotoxin (LT) subunit A and cholera toxin (CT) subunit A. Protein modeling indicates that Pp-ANP2a is structurally similar to CT/LT and likely acts as an ADP-ribosyltransferase. Despite the similarity, Pp-ANP shows several characteristics distinct from CT/LT toxins. Our results indicate that Pp-ANP is a new enterotoxin-like binary toxin with potent and specific activity to nematodes. The potency and specificity of Pp-ANP suggest applications in controlling parasitic nematodes and open an avenue for further research on its mechanism of action and role in bacterium-nematode interaction. IMPORTANCE This study reports the discovery of a new enterotoxin-like binary protein, Pp-ANP, from a Pseudomonas protegens strain. Pp-ANP shows strong nematicidal activity against Caenorhabditis elegans larvae and older-staged worms. It also shows strong activity on other free-living nematodes (Pristionchus pacificus, Panagrellus redivivus, and Acrobeloides sp.). The two subunits, Pp-ANP1a and Pp-ANP2a, can be expressed separately and reconstituted to form the active complex. Pp-ANP shows some distinct characteristics compared with other toxins, including Escherichia coli enterotoxin and cholera toxin. The present study indicates that Pp-ANP is a novel binary toxin and that it has potential applications in controlling parasitic nematodes and in studying toxin-host interaction.

Download Full-text

The use of Caenorhabditis elegans in parasitic nematode research

Parasitology ◽

10.1017/s003118200400647x ◽

2004 ◽

Vol 128 (S1) ◽

pp. S49-S70 ◽

Cited By ~ 39

Author(s):

J. S. GILLEARD

Keyword(s):

Caenorhabditis Elegans ◽

Parasitic Nematode ◽

Expression System ◽

Nematode Species ◽

Current Status ◽

Evolutionary Development ◽

Parasitic Nematodes ◽

Free Living ◽

C Elegans ◽

Free Living Nematode

There is increasing interest in the use of the free-living nematode Caenorhabditis elegans as a tool for parasitic nematode research and there are now a number of compelling examples of its successful application. C. elegans has the potential to become a standard tool for molecular helminthology researchers, just as yeast is routinely used by molecular biologists to study vertebrate biology. However, in order to exploit C. elegans in a meaningful manner, we need a detailed understanding of the extent to which different aspects of C. elegans biology have been conserved with particular groups of parasitic nematodes. This review first considers the current state of knowledge regarding the conservation of genome organisation across the nematode phylum and then discusses some recent evolutionary development studies in free-living nematodes. The aim is to provide some important concepts that are relevant to the extrapolation of information from C. elegans to parasitic nematodes and also to the interpretation of experiments that use C. elegans as a surrogate expression system. In general, examples have been specifically chosen because they highlight the importance of careful experimentation and interpretation of data. Consequently, the focus is on the differences that have been found between nematode species rather than the similarities. Finally, there is a detailed discussion of the current status of C. elegans as a heterologous expression system to study parasite gene function and regulation using successful examples from the literature.

Download Full-text

Chemoreception of Meloidogyne incognita and Caenorhabditis elegans on botanical nematicidals

10.1101/274092 ◽

2018 ◽

Author(s):

Robert Sobkowiak ◽

Natalia Bojarska ◽

Emilia Krzyżaniak ◽

Karolina Wągiel ◽

Nikoletta Ntalli

Keyword(s):

Caenorhabditis Elegans ◽

Meloidogyne Incognita ◽

Plant Secondary Metabolites ◽

Model Organism ◽

Nematode Species ◽

Sublethal Concentration ◽

Parasitic Nematodes ◽

Small Molecular Weight ◽

C Elegans ◽

Aldehydes And Ketones

AbstractPlant–parasitic nematodes cause serious damage to various agricultural crops worldwide, and their control necessitates environmentally safe measures. Plant secondary metabolites of botanical origin are tested here–in to study their effect in Meloidogyne incognita locomotion, being this an important factor affecting host inoculation inside the soil. We compare the effect to the respective behavioral responses of the model organism Caenorhabditis elegans. The tested botanical nematicidals, all reported of activity against Meloidogyne sp. in our previous works, belong to different chemical groups of small molecular weight molecules encompassing acids, alcohols, aldehydes and ketones. Specifically we report on the attractant or repellent properties of trans–anethole, (E,E)–2,4–decadienal, (E)–2–decenal, fostiazate, and 2–undecanone. The treatments for both nematode species were made at sublethal concentration levels, namely 1mM (<EC50), and the chemical control used for the experiment was the commercial nematicide fosthiazate and oxamyl. According to our results, trans–anethole, decenal, and oxamyl act as C. elegans attractants. 2–undecanone strongly attracts M. incognita. These findings can be of use in the development of nematicidal formulates, contributing to the disruption of nematode chemotaxis to root systems.

Download Full-text

Brugia malayi Glycoproteins Detected by the Filariasis Test Strip Antibody AD12.1

Frontiers in Tropical Diseases ◽

10.3389/fitd.2021.729294 ◽

2021 ◽

Vol 2 ◽

Author(s):

Marla I. Hertz ◽

Irene Hamlin ◽

Amy Rush ◽

Philip J. Budge

Keyword(s):

Lectin Binding ◽

Protein Composition ◽

Brugia Malayi ◽

Wuchereria Bancrofti ◽

Test Strip ◽

Parasitic Nematodes ◽

Secretory Proteins ◽

Carbohydrate Epitope ◽

Lectin Array ◽

Human Sera

BackgroundRapid and accurate prevalence mapping of lymphatic filariasis (LF) is necessary to eliminate this disfiguring and disabling neglected tropical disease. Unfortunately, rapid tests such as the filariasis test strip (FTS) for Wuchereria bancrofti, the causative agent of LF in Africa, can cross-react with antigens circulating in some persons infected by the African eye worm, Loa loa, rendering the test unreliable in eleven co-endemic nations. The intended target of the FTS is a heavily glycosylated W. bancrofti circulating filarial antigen (Wb-CFA). Previously, we determined that the FTS monoclonal antibody, AD12.1, which detects a carbohydrate epitope on Wb-CFA, also detects multiple L. loa proteins in cross-reactive sera from persons with loiasis. Since the carbohydrate epitope recognized by AD12.1 is present on glycoproteins of other parasitic nematodes, including Brugia species, it is unclear why reactive glycoproteins are not detected in infections with other filarial parasites.MethodsTo gain a better understanding of the proteins recognized by the FTS diagnostic antibody, we used proteomics and lectin array technology to characterize filarial glycoproteins that are bound by the AD12.1 antibody using Brugia malayi as a model.ResultsDistinct but overlapping sets of AD12 glycoproteins were identified from somatic and excretory/secretory worm products. One of the identified proteins, Bm18019 was confirmed as a secreted AD12-reactive glycoprotein by in-gel proteomics and immunoassays. Based on lectin binding patterns, Brugia AD12-reactive glycoproteins express glycans including core fucose, galactose, N-acetylglucosamine and galactose(β1-3)N-acetylgalactosamine in addition to the epitope recognized by AD12.1. None of the lectins that bound B. malayi AD12 glycoproteins had affinity for the Wb-CFA, highlighting a key difference between it and other AD12 glycoproteins.ConclusionsB. malayi somatic and excretory/secretory proteins are similar to L. loa antigens found in FTS-positive human sera, bolstering the hypothesis that circulating L. loa AD12 antigens result from worm tissue damage or death. The difference in glycan and protein composition between the Wb-CFA and other AD12 glycoproteins can be used to differentiate LF from cross-reactive loiasis.

Download Full-text