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1.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38152979

RESUMO

The identification and characterization of essential genes are central to our understanding of the core biological functions in eukaryotic organisms, and has important implications for the treatment of diseases caused by, for example, cancers and pathogens. Given the major constraints in testing the functions of genes of many organisms in the laboratory, due to the absence of in vitro cultures and/or gene perturbation assays for most metazoan species, there has been a need to develop in silico tools for the accurate prediction or inference of essential genes to underpin systems biological investigations. Major advances in machine learning approaches provide unprecedented opportunities to overcome these limitations and accelerate the discovery of essential genes on a genome-wide scale. Here, we developed and evaluated a large language model- and graph neural network (LLM-GNN)-based approach, called 'Bingo', to predict essential protein-coding genes in the metazoan model organisms Caenorhabditis elegans and Drosophila melanogaster as well as in Mus musculus and Homo sapiens (a HepG2 cell line) by integrating LLM and GNNs with adversarial training. Bingo predicts essential genes under two 'zero-shot' scenarios with transfer learning, showing promise to compensate for a lack of high-quality genomic and proteomic data for non-model organisms. In addition, the attention mechanisms and GNNExplainer were employed to manifest the functional sites and structural domain with most contribution to essentiality. In conclusion, Bingo provides the prospect of being able to accurately infer the essential genes of little- or under-studied organisms of interest, and provides a biological explanation for gene essentiality.


Assuntos
Proteínas de Drosophila , Genes Essenciais , Camundongos , Animais , Proteômica , Drosophila melanogaster/genética , Fluxo de Trabalho , Redes Neurais de Computação , Proteínas/genética , Proteínas dos Microfilamentos/genética , Proteínas de Drosophila/genética
2.
PLoS Pathog ; 18(2): e1010288, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35167626

RESUMO

Urogenital schistosomiasis is caused by the blood fluke Schistosoma haematobium and is one of the most neglected tropical diseases worldwide, afflicting > 100 million people. It is characterised by granulomata, fibrosis and calcification in urogenital tissues, and can lead to increased susceptibility to HIV/AIDS and squamous cell carcinoma of the bladder. To complement available treatment programs and break the transmission of disease, sound knowledge and understanding of the biology and ecology of S. haematobium is required. Hybridisation/introgression events and molecular variation among members of the S. haematobium-group might effect important biological and/or disease traits as well as the morbidity of disease and the effectiveness of control programs including mass drug administration. Here we report the first chromosome-contiguous genome for a well-defined laboratory line of this blood fluke. An exploration of this genome using transcriptomic data for all key developmental stages allowed us to refine gene models (including non-coding elements) and annotations, discover 'new' genes and transcription profiles for these stages, likely linked to development and/or pathogenesis. Molecular variation within S. haematobium among some geographical locations in Africa revealed unique genomic 'signatures' that matched species other than S. haematobium, indicating the occurrence of introgression events. The present reference genome (designated Shae.V3) and the findings from this study solidly underpin future functional genomic and molecular investigations of S. haematobium and accelerate systematic, large-scale population genomics investigations, with a focus on improved and sustained control of urogenital schistosomiasis.


Assuntos
Variação Genética , Genoma de Protozoário , Schistosoma haematobium/genética , Esquistossomose Urinária/parasitologia , Transcriptoma , Animais , Cromossomos/parasitologia , Genes de Protozoários , Genoma , Estudo de Associação Genômica Ampla , Análise de Sequência de DNA
3.
Bioorg Med Chem ; 98: 117540, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38134663

RESUMO

Global challenges with treatment failures and/or widespread resistance in parasitic worms against commercially available anthelmintics lend impetus to the development of new anthelmintics with novel mechanism(s) of action. The free-living nematode Caenorhabditis elegans is an important model organism used for drug discovery, including the screening and structure-activity investigation of new compounds, and target deconvolution. Previously, we conducted a whole-organism phenotypic screen of the 'Pandemic Response Box' (from Medicines for Malaria Venture, MMV) and identified a hit compound, called ABX464, with activity against C. elegans and a related, parasitic nematode, Haemonchus contortus. Here, we tested a series of 44 synthesized analogues to explore the pharmacophore of activity on C. elegans and revealed five compounds whose potency was similar or greater than that of ABX464, but which were not toxic to human hepatoma (HepG2) cells. Subsequently, we employed thermal proteome profiling (TPP), protein structure prediction and an in silico-docking algorithm to predict ABX464-target candidates. Taken together, the findings from this study contribute significantly to the early-stage drug discovery of a new nematocide based on ABX464. Future work is aimed at validating the ABX464-protein interactions identified here, and at assessing ABX464 and associated analogues against a panel of parasitic nematodes, towards developing a new anthelmintic with a mechanism of action that is distinct from any of the compounds currently-available commercially.


Assuntos
Anti-Helmínticos , Nematoides , Quinolinas , Animais , Humanos , Caenorhabditis elegans , Anti-Helmínticos/farmacologia , Anti-Helmínticos/química , Relação Estrutura-Atividade
4.
J Evol Biol ; 36(2): 381-398, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36573922

RESUMO

Genomic data provide valuable insights into pest management issues such as resistance evolution, historical patterns of pest invasions and ongoing population dynamics. We assembled the first reference genome for the redlegged earth mite, Halotydeus destructor (Tucker, 1925), to investigate adaptation to pesticide pressures and demography in its invasive Australian range using whole-genome pool-seq data from regionally distributed populations. Our reference genome comprises 132 autosomal contigs, with a total length of 48.90 Mb. We observed a large complex of ace genes, which has presumably evolved from a long history of organophosphate selection in H. destructor and may contribute towards organophosphate resistance through copy number variation, target-site mutations and structural variants. In the putative ancestral H. destructor ace gene, we identified three target-site mutations (G119S, A201S and F331Y) segregating in organophosphate-resistant populations. Additionally, we identified two new para sodium channel gene mutations (L925I and F1020Y) that may contribute to pyrethroid resistance. Regional structuring observed in population genomic analyses indicates that gene flow in H. destructor does not homogenize populations across large geographic distances. However, our demographic analyses were equivocal on the magnitude of gene flow; the short invasion history of H. destructor makes it difficult to distinguish scenarios of complete isolation vs. ongoing migration. Nonetheless, we identified clear signatures of reduced genetic diversity and smaller inferred effective population sizes in eastern vs. western populations, which is consistent with the stepping-stone invasion pathway of this pest in Australia. These new insights will inform development of diagnostic genetic markers of resistance, further investigation into the multifaceted organophosphate resistance mechanism and predictive modelling of resistance evolution and spread.


Assuntos
Ácaros , Praguicidas , Animais , Austrália , Variações do Número de Cópias de DNA , Ácaros/genética , Organofosfatos , Dinâmica Populacional , Genoma
5.
Nucleic Acids Res ; 49(D1): D998-D1003, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33084874

RESUMO

OGEE is an Online GEne Essentiality database. Gene essentiality is not a static and binary property, rather a context-dependent and evolvable property in all forms of life. In OGEE we collect not only experimentally tested essential and non-essential genes, but also associated gene properties that contributes to gene essentiality. We tagged conditionally essential genes that show variable essentiality statuses across datasets to highlight complex interplays between gene functions and environmental/experimental perturbations. OGEE v3 contains gene essentiality datasets for 91 species; almost doubled from 48 species in previous version. To accommodate recent advances on human cancer essential genes (as known as tumor dependency genes) that could serve as targets for cancer treatment and/or drug development, we expanded the collection of human essential genes from 16 cell lines in previous to 581. These human cancer cell lines were tested with high-throughput experiments such as CRISPR-Cas9 and RNAi; in total, 150 of which were tested by both techniques. We also included factors known to contribute to gene essentiality for these cell lines, such as genomic mutation, methylation and gene expression, along with extensive graphical visualizations for ease of understanding of these factors. OGEE v3 can be accessible freely at https://v3.ogee.info.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Genes Essenciais/genética , Genômica/métodos , Neoplasias/genética , Oncogenes/genética , Animais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Mineração de Dados/métodos , Predisposição Genética para Doença/genética , Humanos , Internet , Neoplasias/patologia , Interferência de RNA
6.
Int J Mol Sci ; 24(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446130

RESUMO

Many parasitic worms have a major adverse impact on human and animal populations worldwide due to the chronicity of their infections. There is a growing body of evidence indicating that extracellular vesicles (EVs) are intimately involved in modulating (suppressing) inflammatory/immune host responses and parasitism. As one of the most pathogenic nematodes of livestock animals, Haemonchus contortus is an ideal model system for EV exploration. Here, employing a multi-step enrichment process (in vitro culture, followed by ultracentrifugation, size exclusion and filtration), we enriched EVs from H. contortus and undertook the first comprehensive (qualitative and quantitative) multi-omic investigation of EV proteins and lipids using advanced liquid chromatography-mass spectrometry and informatics methods. We identified and quantified 561 proteins and 446 lipids in EVs and compared these molecules with those of adult worms. We identified unique molecules in EVs, such as proteins linked to lipid transportation and lipid species (i.e., sphingolipids) associated with signalling, indicating the involvement of these molecules in parasite-host cross-talk. This work provides a solid starting point to explore the functional roles of EV-specific proteins and lipids in modulating parasite-host cross-talk, and the prospect of finding ways of disrupting or interrupting this relationship to suppress or eliminate parasite infection.


Assuntos
Vesículas Extracelulares , Haemonchus , Parasitos , Animais , Humanos , Haemonchus/química , Haemonchus/metabolismo , Proteoma/metabolismo , Lipidômica , Lipídeos
7.
Genomics ; 113(3): 1605-1615, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33677057

RESUMO

The Chinese liver fluke, Clonorchis sinensis, causes the disease clonorchiasis, affecting ~35 million people in regions of China, Vietnam, Korea and the Russian Far East. Chronic clonorchiasis causes cholangitis and can induce a malignant cancer, called cholangiocarcinoma, in the biliary system. Control in endemic regions is challenging, and often relies largely on chemotherapy with one anthelmintic, called praziquantel. Routine treatment carries a significant risk of inducing resistance to this anthelmintic in the fluke, such that the discovery of new interventions is considered important. It is hoped that the use of molecular technologies will assist this endeavour by enabling the identification of drug or vaccine targets involved in crucial biological processes and/or pathways in the parasite. Although draft genomes of C. sinensis have been published, their assemblies are fragmented. In the present study, we tackle this genome fragmentation issue by utilising, in an integrated way, advanced (second- and third-generation) DNA sequencing and informatic approaches to build a high-quality reference genome for C. sinensis, with chromosome-level contiguity and curated gene models. This substantially-enhanced genome provides a resource that could accelerate fundamental and applied molecular investigations of C. sinensis, clonorchiasis and/or cholangiocarcinoma, and assist in the discovery of new interventions against what is a highly significant, but neglected disease-complex.


Assuntos
Clonorquíase , Clonorchis sinensis , Animais , Sequência de Bases , China , Clonorquíase/tratamento farmacológico , Clonorquíase/epidemiologia , Clonorquíase/genética , Clonorchis sinensis/genética , Clonorchis sinensis/metabolismo , Humanos , Federação Russa
8.
Genomics ; 113(3): 1272-1280, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33677058

RESUMO

Here, we present a draft genome of the tapeworm Dipylidium caninum (family Dipylidiidae) and compare it with other cestode genomes. This draft genome of D. caninum is 110 Mb in size, has a repeat content of ~13.4% and is predicted to encode ~10,000 protein-coding genes. We inferred excretory/secretory molecules (representing the secretome), other key groups of proteins (including peptidases, kinases, phosphatases, GTPases, receptors, transporters and ion-channels) and predicted potential intervention targets for future evaluation. Using 144 shared single-copy orthologous sequences, we investigated the genetic relationships of cestodes for which nuclear genomes are available. This study provides first insights into the molecular biology of D. caninum and a new resource for comparative genomic and genetic explorations of this and other flatworms.


Assuntos
Cestoides , Infecções por Cestoides , Platelmintos , Animais , Cestoides/genética , Genômica
9.
Int J Mol Sci ; 23(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35055058

RESUMO

In a quest for new interventions against scabies-a highly significant skin disease of mammals, caused by a parasitic mite Sarcoptes scabiei-we are focusing on finding new intervention targets. RNA interference (RNAi) could be an efficient functional genomics approach to identify such targets. The RNAi pathway is present in S. scabiei and operational in the female adult mite, but other developmental stages have not been assessed. Identifying potential intervention targets in the egg stage is particularly important because current treatments do not kill this latter stage. Here, we established an RNAi tool to silence single-copy genes in S. scabiei eggs. Using sodium hypochlorite pre-treatment, we succeeded in rendering the eggshell permeable to dsRNA without affecting larval hatching. We optimised the treatment of eggs with gene-specific dsRNAs to three single-copy target genes (designated Ss-Cof, Ss-Ddp, and Ss-Nan) which significantly and repeatedly suppressed transcription by ~66.6%, 74.3%, and 84.1%, respectively. Although no phenotypic alterations were detected in dsRNA-treated eggs for Ss-Cof and Ss-Nan, the silencing of Ss-Ddp resulted in a 38% reduction of larval hatching. This RNAi method is expected to provide a useful tool for larger-scale functional genomic investigations for the identification of essential genes as potential drug targets.


Assuntos
Inativação Gênica , Óvulo/metabolismo , Interferência de RNA , Sarcoptes scabiei/genética , Animais , Técnicas de Silenciamento de Genes , Fenótipo , RNA Interferente Pequeno/genética , Suínos , Temperatura
10.
Int J Mol Sci ; 23(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36077116

RESUMO

Here, we explored transcriptomic differences among early egg (Ee), late egg (Le) and adult female (Af) stages of the scabies mite, Sarcoptes scabiei, using an integrative bioinformatic approach. We recorded a high, negative correlation between miRNAs and genes with decreased mRNA transcription between the developmental stages, indicating substantial post-transcriptional repression; we also showed a positive correlation between miRNAs and genes with increased mRNA transcription, suggesting indirect post-transcriptional regulation. The alterations in mRNA transcription between the egg and adult female stages of S. scabiei were inferred to be linked to metabolism (including carbohydrate and lipid degradation, amino acid and energy metabolism), environmental information processing (e.g., signal transduction and signalling molecules), genetic information processing (e.g., transcription and translation) and/or organismal systems. Taken together, these results provide insight into the transcription of this socioeconomically important parasitic mite, with a particular focus on the egg stage. This work encourages further, detailed laboratory studies of miRNA regulation across all developmental stages of S. scabiei and might assist in discovering new intervention targets in the egg stage of S. scabiei.


Assuntos
MicroRNAs , Escabiose , Animais , Feminino , MicroRNAs/genética , RNA Mensageiro , Sarcoptes scabiei/genética , Escabiose/genética , Escabiose/parasitologia , Transcriptoma
11.
PLoS Pathog ; 15(7): e1007960, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31335899

RESUMO

Here, we discovered an endogenous dafachronic acid (DA) in the socioeconomically important parasitic nematode Haemonchus contortus. We demonstrate that DA promotes larval exsheathment and development in this nematode via a relatively conserved nuclear hormone receptor (DAF-12). This stimulatory effect is dose- and time-dependent, and relates to a modulation of dauer-like signalling, and glycerolipid and glycerophospholipid metabolism, likely via a negative feedback loop. Specific chemical inhibition of DAF-9 (cytochrome P450) was shown to significantly reduce the amount of endogenous DA in H. contortus; compromise both larval exsheathment and development in vitro; and modulate lipid metabolism. Taken together, this evidence shows that DA plays a key functional role in the developmental transition from the free-living to the parasitic stage of H. contortus by modulating the dauer-like signalling pathway and lipid metabolism. Understanding the intricacies of the DA-DAF-12 system and associated networks in H. contortus and related parasitic nematodes could pave the way to new, nematode-specific treatments.


Assuntos
Colestenos/metabolismo , Haemonchus/crescimento & desenvolvimento , Haemonchus/metabolismo , Animais , Regulação da Expressão Gênica no Desenvolvimento , Genes de Helmintos , Hemoncose/parasitologia , Hemoncose/veterinária , Haemonchus/patogenicidade , Proteínas de Helminto/química , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Isoxazóis/farmacologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Piperidinas/farmacologia , Piridinas/farmacologia , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico , Transdução de Sinais
12.
PLoS Pathog ; 15(1): e1007513, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30673782

RESUMO

Mesenteric infection by the parasitic blood fluke Schistosoma bovis is a common veterinary problem in Africa and the Middle East and occasionally in the Mediterranean Region. The species also has the ability to form interspecific hybrids with the human parasite S. haematobium with natural hybridisation observed in West Africa, presenting possible zoonotic transmission. Additionally, this exchange of alleles between species may dramatically influence disease dynamics and parasite evolution. We have generated a 374 Mb assembly of the S. bovis genome using Illumina and PacBio-based technologies. Despite infecting different hosts and organs, the genome sequences of S. bovis and S. haematobium appeared strikingly similar with 97% sequence identity. The two species share 98% of protein-coding genes, with an average sequence identity of 97.3% at the amino acid level. Genome comparison identified large continuous parts of the genome (up to several 100 kb) showing almost 100% sequence identity between S. bovis and S. haematobium. It is unlikely that this is a result of genome conservation and provides further evidence of natural interspecific hybridization between S. bovis and S. haematobium. Our results suggest that foreign DNA obtained by interspecific hybridization was maintained in the population through multiple meiosis cycles and that hybrids were sexually reproductive, producing viable offspring. The S. bovis genome assembly forms a highly valuable resource for studying schistosome evolution and exploring genetic regions that are associated with species-specific phenotypic traits.


Assuntos
Hibridização Genética/genética , Schistosoma/genética , África , África Ocidental , Animais , Sequência de Bases/genética , Bovinos , Mapeamento Cromossômico/métodos , DNA/genética , Genoma/genética , Genoma Mitocondrial/genética , Hibridização Genética/fisiologia , Oriente Médio , Filogenia , Proteoma/genética , Especificidade da Espécie , Trematódeos/genética , Sequenciamento Completo do Genoma/métodos
13.
Int J Mol Sci ; 22(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064595

RESUMO

Experimental studies of Caenorhabditis elegans and Drosophila melanogaster have contributed substantially to our understanding of molecular and cellular processes in metazoans at large. Since the publication of their genomes, functional genomic investigations have identified genes that are essential or non-essential for survival in each species. Recently, a range of features linked to gene essentiality have been inferred using a machine learning (ML)-based approach, allowing essentiality predictions within a species. Nevertheless, predictions between species are still elusive. Here, we undertake a comprehensive study using ML to discover and validate features of essential genes common to both C. elegans and D. melanogaster. We demonstrate that the cross-species prediction of gene essentiality is possible using a subset of features linked to nucleotide/protein sequences, protein orthology and subcellular localisation, single-cell RNA-seq, and histone methylation markers. Complementary analyses showed that essential genes are enriched for transcription and translation functions and are preferentially located away from heterochromatin regions of C. elegans and D. melanogaster chromosomes. The present work should enable the cross-prediction of essential genes between model and non-model metazoans.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Evolução Molecular , Genes Essenciais , Aprendizado de Máquina , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Ontologia Genética , Genômica
14.
Int J Mol Sci ; 22(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670420

RESUMO

Long non-coding, tandem-repetitive regions in mitochondrial (mt) genomes of many metazoans have been notoriously difficult to characterise accurately using conventional sequencing methods. Here, we show how the use of a third-generation (long-read) sequencing and informatic approach can overcome this problem. We employed Oxford Nanopore technology to sequence genomic DNAs from a pool of adult worms of the carcinogenic parasite, Schistosoma haematobium, and used an informatic workflow to define the complete mt non-coding region(s). Using long-read data of high coverage, we defined six dominant mt genomes of 33.4 kb to 22.6 kb. Although no variation was detected in the order or lengths of the protein-coding genes, there was marked length (18.5 kb to 7.6 kb) and structural variation in the non-coding region, raising questions about the evolution and function of what might be a control region that regulates mt transcription and/or replication. The discovery here of the largest tandem-repetitive, non-coding region (18.5 kb) in a metazoan organism also raises a question about the completeness of some of the mt genomes of animals reported to date, and stimulates further explorations using a Nanopore-informatic workflow.


Assuntos
Genoma Helmíntico , Genoma Mitocondrial , Sequenciamento por Nanoporos , Schistosoma haematobium/genética , Sequências de Repetição em Tandem , Animais
15.
FASEB J ; 31(10): 4515-4532, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28687609

RESUMO

As a result of limited classes of anthelmintics and an over-reliance on chemical control, there is a great need to discover new compounds to combat drug resistance in parasitic nematodes. Here, we show that deguelin, a plant-derived rotenoid, selectively and potently inhibits the motility and development of nematodes, which supports its potential as a lead candidate for drug development. Furthermore, we demonstrate that deguelin treatment significantly increases gene transcription that is associated with energy metabolism, particularly oxidative phosphorylation and mitoribosomal protein production before inhibiting motility. Mitochondrial tracking confirmed enhanced oxidative phosphorylation. In accordance, real-time measurements of oxidative phosphorylation in response to deguelin treatment demonstrated an immediate decrease in oxygen consumption in both parasitic (Haemonchus contortus) and free-living (Caenorhabditis elegans) nematodes. Consequently, we hypothesize that deguelin is exerting its toxic effect on nematodes as a modulator of oxidative phosphorylation. This study highlights the dynamic biologic response of multicellular organisms to deguelin perturbation.-Preston, S., Korhonen, P. K., Mouchiroud, L., Cornaglia, M., McGee, S. L., Young, N. D., Davis, R. A., Crawford, S., Nowell, C., Ansell, B. R. E., Fisher, G. M., Andrews, K. T., Chang, B. C. H., Gijs, M. A. M., Sternberg, P. W., Auwerx, J., Baell, J., Hofmann, A., Jabbar, A., Gasser, R. B. Deguelin exerts potent nematocidal activity via the mitochondrial respiratory chain.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Rotenona/análogos & derivados , Animais , Anti-Helmínticos/farmacologia , Caenorhabditis elegans/genética , Resistência a Medicamentos/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Rotenona/farmacologia
16.
Antimicrob Agents Chemother ; 60(10): 6034-45, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27458219

RESUMO

Understanding how parasites respond to stress can help to identify essential biological processes. Giardia duodenalis is a parasitic protist that infects the human gastrointestinal tract and causes 200 to 300 million cases of diarrhea annually. Metronidazole, a major antigiardial drug, is thought to cause oxidative damage within the infective trophozoite form. However, treatment efficacy is suboptimal, due partly to metronidazole-resistant infections. To elucidate conserved and stress-specific responses, we calibrated sublethal metronidazole, hydrogen peroxide, and thermal stresses to exert approximately equal pressure on trophozoite growth and compared transcriptional responses after 24 h of exposure. We identified 252 genes that were differentially transcribed in response to all three stressors, including glycolytic and DNA repair enzymes, a mitogen-activated protein (MAP) kinase, high-cysteine membrane proteins, flavin adenine dinucleotide (FAD) synthetase, and histone modification enzymes. Transcriptional responses appeared to diverge according to physiological or xenobiotic stress. Downregulation of the antioxidant system and α-giardins was observed only under metronidazole-induced stress, whereas upregulation of GARP-like transcription factors and their subordinate genes was observed in response to hydrogen peroxide and thermal stressors. Limited evidence was found in support of stress-specific response elements upstream of differentially transcribed genes; however, antisense derepression and differential regulation of RNA interference machinery suggest multiple epigenetic mechanisms of transcriptional control.


Assuntos
Antiprotozoários/farmacologia , Giardia lamblia/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Metronidazol/farmacologia , Transcrição Gênica , Trofozoítos/efeitos dos fármacos , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Epigênese Genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Giardia lamblia/genética , Giardia lamblia/crescimento & desenvolvimento , Giardia lamblia/metabolismo , Glicólise/efeitos dos fármacos , Glicólise/genética , Código das Histonas/efeitos dos fármacos , Temperatura Alta , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Moleculares , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Oxirredução , Estresse Oxidativo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Trofozoítos/crescimento & desenvolvimento , Trofozoítos/metabolismo
17.
Comput Struct Biotechnol J ; 23: 1026-1035, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38435301

RESUMO

Advances in single cell technologies are allowing investigations of a wide range of biological processes and pathways in animals, such as the multicellular model organism Caenorhabditis elegans - a free-living nematode. However, there has been limited application of such technology to related parasitic nematodes which cause major diseases of humans and animals worldwide. With no vaccines against the vast majority of parasitic nematodes and treatment failures due to drug resistance or inefficacy, new intervention targets are urgently needed, preferably informed by a deep understanding of these nematodes' cellular and molecular biology - which is presently lacking for most worms. Here, we created the first single cell atlas for an early developmental stage of Haemonchus contortus - a highly pathogenic, C. elegans-related parasitic nematode. We obtained and curated RNA sequence (snRNA-seq) data from single nuclei from embryonating eggs of H. contortus (150,000 droplets), and selected high-quality transcriptomic data for > 14,000 single nuclei for analysis, and identified 19 distinct clusters of cells. Guided by comparative analyses with C. elegans, we were able to reproducibly assign seven cell clusters to body wall muscle, hypodermis, neuronal, intestinal or seam cells, and identified eight genes that were transcribed in all cell clusters/types, three of which were inferred to be essential in H. contortus. Two of these genes (i.e. Hc-eef-1A and Hc-eef1G), coding for eukaryotic elongation factors (called Hc-eEF1A and Hc-eEF1G), were also demonstrated to be transcribed and expressed in all key developmental stages of H. contortus. Together with these findings, sequence- and structure-based comparative analyses indicated the potential of Hc-eEF1A and/or Hc-eEF1G as intervention targets within the protein biosynthesis machinery of H. contortus. Future work will focus on single cell studies of all key developmental stages and tissues of H. contortus, and on evaluating the suitability of the two elongation factor proteins as drug targets in H. contortus and related nematodes, with a view to finding new nematocidal drug candidates.

18.
Int J Parasitol Drugs Drug Resist ; 24: 100522, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38295619

RESUMO

Within the context of our anthelmintic discovery program, we recently identified and evaluated a quinoline derivative, called ABX464 or obefazimod, as a nematocidal candidate; synthesised a series of analogues which were assessed for activity against the free-living nematode Caenorhabditis elegans; and predicted compound-target relationships by thermal proteome profiling (TPP) and in silico docking. Here, we logically extended this work and critically evaluated the anthelmintic activity of ABX464 analogues on Haemonchus contortus (barber's pole worm) - a highly pathogenic nematode of ruminant livestock. First, we tested a series of 44 analogues on H. contortus (larvae and adults) to investigate the nematocidal pharmacophore of ABX464, and identified one compound with greater potency than the parent compound and showed moderate activity against a select number of other parasitic nematodes (including Ancylostoma, Heligmosomoides and Strongyloides species). Using TPP and in silico modelling studies, we predicted protein HCON_00074590 (a predicted aldo-keto reductase) as a target candidate for ABX464 in H. contortus. Future work aims to optimise this compound as a nematocidal candidate and investigate its pharmacokinetic properties. Overall, this study presents a first step toward the development of a new nematocide.


Assuntos
Anti-Helmínticos , Haemonchus , Nematoides , Quinolinas , Animais , Antinematódeos/farmacologia , Anti-Helmínticos/farmacologia , Relação Estrutura-Atividade , Caenorhabditis elegans , Quinolinas/farmacologia
19.
Mol Ecol Resour ; 23(4): 833-843, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36727564

RESUMO

Clonorchis sinensis is a carcinogenic liver fluke that causes clonorchiasis-a neglected tropical disease (NTD) affecting ~35 million people worldwide. No vaccine is available, and chemotherapy relies on one anthelmintic, praziquantel. This parasite has a complex life history and is known to infect a range of species of intermediate (freshwater snails and fish) and definitive (piscivorous) hosts. Despite this biological complexity and the impact of this biocarcinogenic pathogen, there has been no previous study of molecular variation in this parasite on a genome-wide scale. Here, we conducted the first extensive nuclear genomic exploration of C. sinensis individuals (n = 152) representing five distinct populations from mainland China, and one from Far East Russia, and revealed marked genetic variation within this species between "northern" and "southern" geographical regions. The discovery of this variation indicates the existence of biologically distinct variants within C. sinensis, which may have distinct epidemiology, pathogenicity and/or chemotherapic responsiveness. The detection of high heterozygosity within C. sinensis specimens suggests that this parasite has developed mechanisms to readily adapt to changing environments and/or host species during its life history/evolution. From an applied perspective, the identification of invariable genes could assist in finding new intervention targets in this parasite, given the major clinical relevance of clonorchiasis. From a technical perspective, the genomic-informatic workflow established herein will be readily applicable to a wide range of other parasites that cause NTDs.


Assuntos
Clonorquíase , Clonorchis sinensis , Animais , Clonorchis sinensis/genética , Clonorquíase/diagnóstico , Clonorquíase/epidemiologia , Clonorquíase/parasitologia , Variação Genética , Ásia Oriental , China/epidemiologia
20.
Biotechnol Adv ; 54: 107822, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34461202

RESUMO

The availability of high-quality genomes and advances in functional genomics have enabled large-scale studies of essential genes in model eukaryotes, including the 'elegant worm' (Caenorhabditis elegans; Nematoda) and the 'vinegar fly' (Drosophila melanogaster; Arthropoda). However, this is not the case for other, much less-studied organisms, such as socioeconomically important parasites, for which functional genomic platforms usually do not exist. Thus, there is a need to develop innovative techniques or approaches for the prediction, identification and investigation of essential genes. A key approach that could enable the prediction of such genes is machine learning (ML). Here, we undertake an historical review of experimental and computational approaches employed for the characterisation of essential genes in eukaryotes, with a particular focus on model ecdysozoans (C. elegans and D. melanogaster), and discuss the possible applicability of ML-approaches to organisms such as socioeconomically important parasites. We highlight some recent results showing that high-performance ML, combined with feature engineering, allows a reliable prediction of essential genes from extensive, publicly available 'omic data sets, with major potential to prioritise such genes (with statistical confidence) for subsequent functional genomic validation. These findings could 'open the door' to fundamental and applied research areas. Evidence of some commonality in the essential gene-complement between these two organisms indicates that an ML-engineering approach could find broader applicability to ecdysozoans such as parasitic nematodes or arthropods, provided that suitably large and informative data sets become/are available for proper feature engineering, and for the robust training and validation of algorithms. This area warrants detailed exploration to, for example, facilitate the identification and characterisation of essential molecules as novel targets for drugs and vaccines against parasitic diseases. This focus is particularly important, given the substantial impact that such diseases have worldwide, and the current challenges associated with their prevention and control and with drug resistance in parasite populations.


Assuntos
Caenorhabditis elegans , Genes Essenciais , Animais , Caenorhabditis elegans/genética , Drosophila melanogaster/genética , Eucariotos/genética , Genômica , Aprendizado de Máquina
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