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[
Trends Biotechnol,
1996]
Toxicity bioassays rely largely on lethality measurements. Such assays are generally lengthy and expensive, and provide little information on mechanisms of toxicity. A desire to understand the mechanisms by which cells respond to physical and chemical stresses has led to interest in measuring stress proteins as toxicological endpoints. Transgenic strains of the nematode Caenorhabditis elegans that carry a reporter enzyme under control of a stress-inducible promoter have been created. The reporter is easily quantified in intact nematodes, and it responds to a wide range of chemical stressors. Therefore, transgenic C. elegans can provide the basis for a wide range of quick, simple and informative bioassays.
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[
Neuromuscul Disord,
2002]
We investigated the function of dystrophin in the nematode Caenorhabditis elegans. Although nematodes and mammals diverged early in evolution, their muscles share many structural and molecular features, thus rendering C. elegans relevant as a model to study muscle function. Dystrophin, dystrobrevin, dystroglycans and several sarcoglycans have conserved homologues in the genome of C. elegans. The major strength of the model comes from its genetic tractability, which allows the quick and easy manipulation of gene expression, either to inactivate genes, or to create transgenic animals. Over the last 2 years, work on C. elegans dystrophin has led to the identification of a putative new member of the dystrophin-glycoprotein complex, and has brought additional data suggesting that dystrophin mutations affect ion
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[
Genetics,
2016]
The use of next-generation sequencing (NGS) has revolutionized the way phenotypic traits are assigned to genes. In this review, we describe NGS-based methods for mapping a mutation and identifying its molecular identity, with an emphasis on applications in Caenorhabditis elegans In addition to an overview of the general principles and concepts, we discuss the main methods, provide practical and conceptual pointers, and guide the reader in the types of bioinformatics analyses that are required. Owing to the speed and the plummeting costs of NGS-based methods, mapping and cloning a mutation of interest has become straightforward, quick, and relatively easy. Removing this bottleneck previously associated with forward genetic screens has significantly advanced the use of genetics to probe fundamental biological processes in an unbiased manner.
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[
Trends Genet,
1997]
The 100 Mb sequence of the nematode Caenorhabditis elegans genome will be completed in 1998. More than 10,000 predicted genes have been identified to date, so it should come as no surprise to find a C. elegans homologue of your favourite gene in current databases. For some investigators, the discovery of a C. elegans homologue represents a unique opportunity to adopt a genetic approach and to take advantage of the extensive repertoire of C. elegans gene characterization and manipulation tools. RNA injection provides a quick and efficient method for obtaining clues about wild-type gene function. Reverse genetic approaches also make it feasible to screen de novo for mutations in specific gene sequences. This review highlights the resources available for analysing a C. elegans homologue, starting from the gene sequence and proceeding to the biological function.
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Phytomedicine,
2017]
BACKGROUND: Biofilms contribute to the pathogenesis of many chronic and difficult-to eradicate infections whose treatment is complicated due to the intrinsic resistance to conventional antibiotics. As a consequence, there is an urgent need for strategies that can be used for the prevention and treatment of biofilm-associated infections. The combination therapy comprising an antimicrobial drug with a low molecular weight (MW) natural product and an antimicrobial drug (antifungal or antibacterial) appeared as a good alternative to eradicate biofilms. PURPOSE: The aims of this review were to perform a literature search on the different natural products that have showed the ability of potentiating the antibiofilm capacity of antimicrobial drugs, to analyze which are the antimicrobial drugs most used in combination, and to have a look on the microbial species most used to prepare biofilms. RESULTS: Seventeen papers, nine on combinations against antifungal biofilms and eight against antibacterial biofilms were collected. Within the text, the following topics have been developed: breaf history of the discovery of biofilms; stages in the development of a biofilm; the most used methodologies to assess antibiofilm-activity; the natural products with capacity of eradicating biofilms when acting alone; the combinations of low MW natural products with antibiotics or antifungal drugs as a strategy for eradicating microbial biofilms and a list of the low MW natural products that potentiate the inhibition capacity of antifungal and antibacterial drugs against biofilms. CONCLUSIONS AND PERSPECTIVES: Regarding combinations against antifungal biofilms, eight over the nine collected works were carried out with in vitro studies while only one was performed with in vivo assays by using Caenorhabditis elegans nematode. All studies use biofilms of the Candida genus. A 67% of the potentiators were monoterpenes and sesquiterpenes and six over the nine works used FCZ as the antifungal drug. The activity of AmpB and Caspo was enhanced in one and two works respectively. Regarding combinations against bacterial biofilms, in vitro studies were performed in all works by using several different methods of higher variety than the used against fungal biofilms. Biofilms of both the gram (+) and gram (-) bacteria were prepared, although biofilm of Staphylococcus spp. were the most used in the collected works. Among the discovered potentiators of antibacterial drugs, 75% were terpenes, including mono, di- and triterpenes, and, among the atibacterial drugs, several structurally diverse types were used in the combinations: aminoglycosides, -lactams, glucopeptides and fluoroquinolones. The potentiating capacity of natural products, mainly terpenes, on the antibiofilm effect of antimicrobial drugs opens a wide range of possibilities for the combination antimicrobial therapy. More in vivo studies on combinations of natural products with antimicrobial drugs acting against biofilms are highly required to cope the difficult to treat biofilm-associated infections.
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Trends Cell Biol,
2019]
Fluorescent proteins have revolutionized biomedical research as they are easy to use for protein tagging, cope without fixation or permeabilization, and thus, enable live cell imaging in various models. Current methods allow easy and quick integration of fluorescent markers to endogenous genes of interest. In this review, we introduce the three central methods, zinc finger nucleases (ZFNs), transcription activator-like effectors (TALENs), and CRISPR, that have been widely used to manipulate cells or organisms. Focusing on CRISPR technology, we give an overview on homology-directed repair (HDR)-, microhomology-mediated end joining (MMEJ)-, and nonhomologous end joining (NHEJ)-based strategies for the knock-in of markers, figure out recent developments of the technique for highly efficient knock-in, and demonstrate pros and cons. We highlight the unique aspects of fluorescent protein knock-ins and pinpoint specific improvements and perspectives, like the combination of editing with stem cell derived organoid development.
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[
Trends Genet,
1996]
In the 15 years since they were first discovered, Wnt proteins have emerged as one of the pre-eminent families of signalling molecules in animal development. Everything, from axis specification to kidney development, from the polarity of a mouse limb to the polarity of a nematode cell division, apparently depends one way or another on the activity of these secreted factors. Yet, while the discovery and characterization of Wnt genes has continued apace, progress in discovering how Wnt signals are received and interpreted has been rather less impressive. When confronted with their failure to identify a receptor, Wnt aficionados are quick to point to the notorious difficulty in obtaining soluble forms of these proteins as the principal obstacle to their progress. Recognizing this problem, Roel Nusse took the inspired step of switching to Drosophila to study Wnt signalling. The reasoning was simple: if only a Wnt gene could be discovered in the fly, it should be relatively trivial to use the sophisticated genetics of Drosophila to identify mutations in the reception pathway. Now, some 10 years later, genetic analysis has, indeed, led Nusse and his colleagues to a putative Wnt receptor-but the route has been rather less direct than might originally have been anticipated.
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Klin Onkol,
2024]
BACKGROUND: Early diagnosis of cancer is essential for its effective treatment. Currently, established screening tests are cancer-specific and require screening for each type of cancer separately. The primary objective of cancer research is to develop methods that can detect multiple types of tumors from a single body fluid sample. Multicancer early detection tests aim to detect fragments of circulating tumor DNA, cell-free DNA, circulating microRNAs, or proteins released by cancer cells in the patient's body fluids. However, these tests are not suitable for routine cancer prevention due to their high cost. Therefore, in recent years, cancer screening tests have been developed to detect volatile organic compounds in urine using living organisms, such as nematodes, Caenorhabditis elegans. Measuring only 1&#
x2005;mm in length, C. elegans has the potential to offer a new, efficient, cost-effective, quick, and painless method to detect the presence of tumor. PURPOSE: The purpose of this review is to present an overview of the literature on the development and validation of C. elegans-based cancer detection methods. The potential benefits of these assays are significant, as they could become a valuable tool for the early identification and diagnosis of cancer, even though this research is still in its initial stages of development.
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Le Mentec H, Heindel JJ, Mohajer N, Podechard N, Kassotis CD, Touma C, Babin PJ, Howard S, Shree N, Martin-Chouly C, Lagadic-Gossmann D, Choudhury M, Munic Kos V, Barouki R, Bansal A, Ji Kim M, Legrand A, Vom Saal FS, Audouze K, Langouet S, Blumberg B
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Biochem Pharmacol,
2022]
There is increasing evidence of a role for environmental contaminants in disrupting metabolic health in both humans and animals. Despite a growing need for well-understood models for evaluating adipogenic and potential obesogenic contaminants, there has been a reliance on decades-old in vitro models that have not been appropriately managed by cell line providers. There has been a quick rise in available in vitro models in the last ten years, including commercial availability of human mesenchymal stem cell and preadipocyte models; these models require more comprehensive validation but demonstrate real promise in improved translation to human metabolic health. There is also progress in developing three-dimensional and co-culture techniques that allow for the interrogation of a more physiologically relevant state. While diverse rodent models exist for evaluating putative obesogenic and/or adipogenic chemicals in a physiologically relevant context, increasing capabilities have been identified for alternative model organisms such as Drosophila, C. elegans, zebrafish, and medaka in metabolic health testing. These models have several appreciable advantages, including most notably their size, rapid development, large brood sizes, and ease of high-resolution lipid accumulation imaging throughout the organisms. They are anticipated to expand the capabilities of metabolic health research, particularly when coupled with emerging obesogen evaluation techniques as described herein.
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[
WormBook,
2006]
Contrary to textbook dogma, nematodes are not only highly diverse, but often also complex and biologically specialized metazoans. Just a few of the many fascinating adaptations are reviewed in this chapter, as a prelude to a quick tour through phylogenetic relationships within the phylum. Small Subunit rDNA sequences have confirmed several controversial prior hypotheses, as well as revealing some unexpected relationships, resulting in a recent proposal for revised classification. Three major lineages exist within the phylum: Chromadoria, Enoplia and Dorylaimia. The exact order of appearance of these lineages is not yet resolved, which also leaves room for uncertainty about the biology and morphology of the exclusive common ancestor of nematodes. Enoplia and Dorylaimia differ considerably in many respects from C. elegans, which is a member of Chromadoria. The latter group is extremely diverse in its own right, for example in ecological range, in properties of the cuticle and in structure of the pharynx. The formerly relatively widely accepted class Secernentea is deeply nested within Chromadoria, and has therefore recently been relegated to the rank and name of order Rhabditida. Within this order, closer relatives of C. elegans include strongylids, diplogasterids and bunonematids. Tylenchs, cephalobs and panagrolaimids are also members of Rhabditida, albeit probably more distantly related to C. elegans.