ABSTRACT
Echinococcus granulosus sensu lato (s.l.) is a species complex with the potential to cause cystic echinococcosis (CE). Contact with the feces of domestic dogs (Canis familiaris) fed with raw viscera of intermediate livestock hosts is a risk factor for this infection in the southern region of Brazil. Although the region has been considered endemic to CE for many years, molecular data regarding the species of the complex causing CE in humans are scarce. This study aimed to perform a molecular analysis of the biological fluid from a human liver cyst to investigate the species responsible for CE. Genetic material obtained from the hydatid fluid of a hepatic cyst from a human with CE was subjected to PCR to amplify mitochondrial and nuclear DNA sequences. The phylogenetic analysis confirmed the human infection by Echinococcus canadensis G7 in the state of Paraná, Brazil. This is the first molecular record of E. canadensis G7 infecting a human in Brazil, and it is important to reiterate the risk of human CE caused by this species in South America, as reported by a previous study in Patagonia, Argentina. From the epidemiological point of view, this finding is of great relevance for the southern region of Brazil, since this parasite has previously only been detected in pigs in the state of Rio Grande do Sul, neighboring Paraná. The finding points to the importance of this identification in the molecular epidemiology of E. granulosus s.l., especially in South America.
Subject(s)
DNA, Helminth , Echinococcus , Phylogeny , Animals , Humans , Male , Brazil/epidemiology , DNA, Helminth/genetics , DNA, Mitochondrial/genetics , Echinococcosis/veterinary , Echinococcosis/parasitology , Echinococcosis/epidemiology , Echinococcus/genetics , Echinococcus/classification , Echinococcus/isolation & purification , Polymerase Chain Reaction , Sequence Analysis, DNAABSTRACT
Aspergillus fumigatus represents a public health problem due to the high mortality rate in immunosuppressed patients and the emergence of antifungal-resistant isolates. Protein acetylation is a crucial post-translational modification that controls gene expression and biological processes. The strategic manipulation of enzymes involved in protein acetylation has emerged as a promising therapeutic approach for addressing fungal infections. Sirtuins, NAD+-dependent lysine deacetylases, regulate protein acetylation and gene expression in eukaryotes. However, their role in the human pathogenic fungus A. fumigatus remains unclear. This study constructs six single knockout strains of A. fumigatus and a strain lacking all predicted sirtuins (SIRTKO). The mutant strains are viable under laboratory conditions, indicating that sirtuins are not essential genes. Phenotypic assays suggest sirtuins' involvement in cell wall integrity, secondary metabolite production, thermotolerance, and virulence. Deletion of sirE attenuates virulence in murine and Galleria mellonella infection models. The absence of SirE alters the acetylation status of proteins, including histones and non-histones, and triggers significant changes in the expression of genes associated with secondary metabolism, cell wall biosynthesis, and virulence factors. These findings encourage testing sirtuin inhibitors as potential therapeutic strategies to combat A. fumigatus infections or in combination therapy with available antifungals.
Subject(s)
Aspergillosis , Aspergillus fumigatus , Sirtuins , Aspergillus fumigatus/pathogenicity , Aspergillus fumigatus/genetics , Aspergillus fumigatus/enzymology , Sirtuins/genetics , Sirtuins/metabolism , Virulence , Animals , Mice , Aspergillosis/microbiology , Aspergillosis/drug therapy , Acetylation , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal , Virulence Factors/genetics , Virulence Factors/metabolism , Moths/microbiologyABSTRACT
Early diagnosis of potentially malignant disorders, such as oral epithelial dysplasia, is the most reliable way to prevent oral cancer. Computational algorithms have been used as an auxiliary tool to aid specialists in this process. Usually, experiments are performed on private data, making it difficult to reproduce the results. There are several public datasets of histological images, but studies focused on oral dysplasia images use inaccessible datasets. This prevents the improvement of algorithms aimed at this lesion. This study introduces an annotated public dataset of oral epithelial dysplasia tissue images. The dataset includes 456 images acquired from 30 mouse tongues. The images were categorized among the lesion grades, with nuclear structures manually marked by a trained specialist and validated by a pathologist. Also, experiments were carried out in order to illustrate the potential of the proposed dataset in classification and segmentation processes commonly explored in the literature. Convolutional neural network (CNN) models for semantic and instance segmentation were employed on the images, which were pre-processed with stain normalization methods. Then, the segmented and non-segmented images were classified with CNN architectures and machine learning algorithms. The data obtained through these processes is available in the dataset. The segmentation stage showed the F1-score value of 0.83, obtained with the U-Net model using the ResNet-50 as a backbone. At the classification stage, the most expressive result was achieved with the Random Forest method, with an accuracy value of 94.22%. The results show that the segmentation contributed to the classification results, but studies are needed for the improvement of these stages of automated diagnosis. The original, gold standard, normalized, and segmented images are publicly available and may be used for the improvement of clinical applications of CAD methods on oral epithelial dysplasia tissue images.
Subject(s)
Neural Networks, Computer , Mice , Animals , Machine Learning , Algorithms , Mouth Neoplasms/diagnostic imaging , Mouth Neoplasms/pathology , Image Processing, Computer-Assisted/methods , Databases, Factual , Precancerous Conditions/diagnostic imaging , Precancerous Conditions/pathology , Tongue/pathology , Tongue/diagnostic imaging , Humans , Mouth Mucosa/pathology , Mouth Mucosa/diagnostic imagingABSTRACT
The coproparasitological examination of dogs (n=278) from two Brazilian biomes (Amazon [AZ] and Atlantic Forest [AF]) by centrifugal flotation demonstrated positivity values of 54.2% (AF) and 48.5% (AZ). The most prevalent parasites in AF were hookworms (81.0% - 47/58), Toxocara sp. (17.3% - 10/58) and Trichuris vulpis (12.1% - 7/58); while in AZ they were hookworms (86.7% - 72/83), Toxocara sp. (18.1% - 15/83), Dipylidium caninum (13.3% - 11/83) and T. vulpis (10.8% - 9/83). PCR was performed using the partial mitochondrial genes cytochrome c oxidase subunit 1 (pcox1) and NADH dehydrogenase 1 (pnad1) in 25 fecal samples positive for Toxocara sp. eggs and found one sample positive for pcox1 and six positives for pnad1. The sequencing of these samples was unsuccessful due to the difficulties inherent in copro-PCR+sequencing. The sequencing of 14 samples of T. canis adult helminths retrieved 11 sequences of 414 bp for pcox1 and nine sequences of 358 bp for pnad1. The phylogenetic trees of these sequences confirmed the species T. canis. Intraspecific genetic variation was only observed for pnad1. This is the second study involving molecular analysis of T. canis in dogs from Brazil and adds new information through the use of pnad1.
Subject(s)
Dog Diseases , Helminths , Toxocara canis , Animals , Dogs , Toxocara canis/genetics , Brazil , Phylogeny , Ecosystem , Forests , Dog Diseases/diagnosis , Dog Diseases/parasitology , Feces/parasitology , PrevalenceABSTRACT
Schistosomes are blood flukes with specialised tissues and organs, each one playing a pivotal role in perpetuating the parasite life cycle. Herein, we describe a detailed methodology for preserving the proteome of adult Schistosoma mansoni worms during manual dissection for enrichment of tissues associated with the parasite's alimentary tract. We provide step-by-step directions for specimen storage and dissection while in preservative solution, tissue homogenisation, protein extraction and digestion using a methodology fully compatible with downstream quantitative liquid chromatography-mass spectrometry analysis. Our methodology uses label-free and QconCAT-based absolute quantification for detection of S. mansoni oesophageal gland products proposed as vaccine candidates. Through stabilisation of the proteome and minimising sample degradation during dissection our approach has allowed us to access the hidden proteome of target tissues not readily available from total lysates because of their small volume. This protocol can be replicated or adapted to other Schistosoma species lacking quantitative proteomics characterisation of specialised tissues for discovery of proteins with potential diagnostic and therapeutic utility.
Subject(s)
Liquid Chromatography-Mass Spectrometry , Proteomics , Animals , Proteomics/methods , Chromatography, Liquid , Proteome/metabolism , Tandem Mass Spectrometry , Schistosoma mansoni/chemistry , Schistosoma mansoni/metabolismABSTRACT
In this work, a computational scheme is proposed to identify the main combinations of handcrafted descriptors and deep-learned features capable of classifying histological images stained with hematoxylin and eosin. The handcrafted descriptors were those representatives of multiscale and multidimensional fractal techniques (fractal dimension, lacunarity and percolation) applied to quantify the histological images with the corresponding representations via explainable artificial intelligence (xAI) approaches. The deep-learned features were obtained from different convolutional neural networks (DenseNet-121, EfficientNet-b2, Inception-V3, ResNet-50 and VGG-19). The descriptors were investigated through different associations. The most relevant combinations, defined through a ranking algorithm, were analyzed via a heterogeneous ensemble of classifiers with the support vector machine, naive Bayes, random forest and K-nearest neighbors algorithms. The proposed scheme was applied to histological samples representative of breast cancer, colorectal cancer, oral dysplasia and liver tissue. The best results were accuracy rates of 94.83% to 100%, with the identification of pattern ensembles for classifying multiple histological images. The computational scheme indicated solutions exploring a reduced number of features (a maximum of 25 descriptors) and with better performance values than those observed in the literature. The presented information in this study is useful to complement and improve the development of computer-aided diagnosis focused on histological images.
ABSTRACT
The poor prognosis of head and neck cancer (HNC) is associated with metastasis within the lymph nodes (LNs). Herein, the proteome of 140 multisite samples from a 59-HNC patient cohort, including primary and matched LN-negative or -positive tissues, saliva, and blood cells, reveals insights into the biology and potential metastasis biomarkers that may assist in clinical decision-making. Protein profiles are strictly associated with immune modulation across datasets, and this provides the basis for investigating immune markers associated with metastasis. The proteome of LN metastatic cells recapitulates the proteome of the primary tumor sites. Conversely, the LN microenvironment proteome highlights the candidate prognostic markers. By integrating prioritized peptide, protein, and transcript levels with machine learning models, we identify nodal metastasis signatures in blood and saliva. We present a proteomic characterization wiring multiple sites in HNC, thus providing a promising basis for understanding tumoral biology and identifying metastasis-associated signatures.
Subject(s)
Head and Neck Neoplasms , Proteome , Humans , Lymphatic Metastasis/pathology , Proteomics , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/pathology , Lymph Nodes/pathology , Tumor MicroenvironmentABSTRACT
Subsistence hunting is the main source of protein for forest reserve dwellers, contributing to the development of spurious infections by Calodium hepaticum, frequently associated with the consumption of the liver from wild mammals. The prevalence of infections by soil-transmitted helminths (STHs) and intestinal protozoa is considered an indicator of the social vulnerability of a country, besides providing information on habits, customs and quality of life of a given population. Intestinal parasites mostly affect poor rural communities with limited access to clean water and adequate sanitation. This study reports the results of a parasitological survey carried out in 2017 and 2019, in two municipalities (Xapuri and Sena Madureira) in Acre State. Stool samples were collected from 276 inhabitants. Upon receipt, each sample was divided into two aliquots. Fresh samples without preservative were processed and examined by the Kato-Katz technique. Samples fixed in 10% formalin were processed by the spontaneous sedimentation and the centrifugal sedimentation techniques. Calodium hepaticum eggs were found in three stool samples. The overall STH prevalence was 44.9%. The hookworm prevalence (19.2%) was higher than that of Ascaris lumbricoides (2.5%) and Trichuris trichiura (0.7%), an unexpected finding for municipalities belonging to the Western Brazilian Amazon. When considering parasites transmitted via the fecal-oral route, Endolimax nana and Entamoeba coli showed the highest positivity rates, of 13% and 10.9%, respectively. This study is the first report of spurious infection by C. hepaticum among forest reserve dwellers that consume undercooked liver of lowland pacas. Additionally, this is the first report of Blastocystis sp. in Acre State.
Subject(s)
Helminthiasis , Intestinal Diseases, Parasitic , Parasites , Ancylostomatoidea , Animals , Feces , Forests , Helminthiasis/diagnosis , Helminthiasis/epidemiology , Intestinal Diseases, Parasitic/diagnosis , Intestinal Diseases, Parasitic/epidemiology , Prevalence , Quality of Life , SoilABSTRACT
ABSTRACT Subsistence hunting is the main source of protein for forest reserve dwellers, contributing to the development of spurious infections by Calodium hepaticum, frequently associated with the consumption of the liver from wild mammals. The prevalence of infections by soil-transmitted helminths (STHs) and intestinal protozoa is considered an indicator of the social vulnerability of a country, besides providing information on habits, customs and quality of life of a given population. Intestinal parasites mostly affect poor rural communities with limited access to clean water and adequate sanitation. This study reports the results of a parasitological survey carried out in 2017 and 2019, in two municipalities (Xapuri and Sena Madureira) in Acre State. Stool samples were collected from 276 inhabitants. Upon receipt, each sample was divided into two aliquots. Fresh samples without preservative were processed and examined by the Kato-Katz technique. Samples fixed in 10% formalin were processed by the spontaneous sedimentation and the centrifugal sedimentation techniques. Calodium hepaticum eggs were found in three stool samples. The overall STH prevalence was 44.9%. The hookworm prevalence (19.2%) was higher than that of Ascaris lumbricoides (2.5%) and Trichuris trichiura (0.7%), an unexpected finding for municipalities belonging to the Western Brazilian Amazon. When considering parasites transmitted via the fecal-oral route, Endolimax nana and Entamoeba coli showed the highest positivity rates, of 13% and 10.9%, respectively. This study is the first report of spurious infection by C. hepaticum among forest reserve dwellers that consume undercooked liver of lowland pacas. Additionally, this is the first report of Blastocystis sp. in Acre State.
ABSTRACT
Introduction: Oral squamous cell carcinoma (OSCC) ranks among the top 10 leading causes of cancer worldwide, with 5-year survival rate of about 50%, high lymph node metastasis, and relapse rates. The OSCC diagnosis, prognosis, and treatment are mostly based on the clinical TNM classification. There is an urgent need for the discovery of biomarkers and therapeutic targets to assist in the clinical decision-making process.Areas covered: We summarize proteomic studies of the OSCC tumor, immune microenvironment, potential liquid biopsy sites, and post-translational modifications trying to retrieve information in the discovery and verification or (pre)validation phases. The search strategy was based on the combination of MeSH terms and expert refinement.Expert opinion: Untargeted combined with targeted proteomics are strategies that provide reliable and reproducible quantitation of proteins and are the methods of choice of many groups worldwide. Undoubtedly, proteomics has been contributing to the understanding of OSCC progression and uncovers potential candidates as biomarker or therapeutic targets. Nevertheless, none of these targets are available in the clinical practice yet. The scientific community needs to overcome the limitations by investing in robust experimental designs to strengthen the value of the findings, leveraging the translation of knowledge, and further supporting clinical decisions.
Subject(s)
Carcinoma, Squamous Cell , Mouth Neoplasms , Biomarkers, Tumor , Humans , Mouth Neoplasms/diagnosis , Prognosis , Proteomics , Tumor MicroenvironmentABSTRACT
Saliva is a biofluid that maintains the health of oral tissues and the homeostasis of oral microbiota. Studies have demonstrated that Oral squamous cell carcinoma (OSCC) patients have different salivary microbiota than healthy individuals. However, the relationship between these microbial differences and clinicopathological outcomes is still far from conclusive. Herein, we investigate the capability of using metagenomic and metaproteomic saliva profiles to distinguish between Control (C), OSCC without active lesion (L0), and OSCC with active lesion (L1) patients. The results show that there are significantly distinct taxonomies and functional changes in L1 patients compared to C and L0 patients, suggesting compositional modulation of the oral microbiome, as the relative abundances of Centipeda, Veillonella, and Gemella suggested by metagenomics are correlated with tumor size, clinical stage, and active lesion. Metagenomics results also demonstrated that poor overall patient survival is associated with a higher relative abundance of Stenophotromonas, Staphylococcus, Centipeda, Selenomonas, Alloscordovia, and Acitenobacter. Finally, compositional and functional differences in the saliva content by metaproteomics analysis can distinguish healthy individuals from OSCC patients. In summary, our study suggests that oral microbiota and their protein abundance have potential diagnosis and prognosis value for oral cancer patients. Further studies are necessary to understand the role of uniquely detected metaproteins in the microbiota of healthy and OSCC patients as well as the crosstalk between saliva host proteins and the oral microbiome present in OSCC.
Subject(s)
Saliva/microbiology , Squamous Cell Carcinoma of Head and Neck/microbiology , Adult , Aged , Cohort Studies , Female , Humans , Male , Metagenomics/methods , Microbiota/genetics , Middle Aged , Mouth Neoplasms/metabolism , Mouth Neoplasms/microbiology , Prognosis , Proteomics/methods , Squamous Cell Carcinoma of Head and Neck/metabolismABSTRACT
We used two fossil teeth from South American Pleistocene mammals to obtain subsuperficial acid etching samples. We employed samples from the species Notiomastodon platensis and Myocastor cf. coypus for the enamel etchings. The controls included an extant rodent (rat). After the first etching was discarded, a second 20-s etching (i.e., subsuperficial) was directly collected with a ZipTip and injected into an LTQ Orbitrap Velos for MS analysis. The peptides were identified with different software programs that used Peptide Spectrum Match (PSM) and de novo sequencing including similarity search strategies. Most of the peptides that were recovered from the enamel of the fossils belonged to enamel-specific proteins. To our knowledge, this is the first study that has described the recovery of enamel peptide molecules from extinct South American taxa, indicating that enamel peptide data from late Pleistocene fossils can be employed as an additional parameter for phylogenetic analysis, and that the sample can be obtained by a very conservative acid etching, with almost no damage to the fossils. SIGNIFICANCE: This study shows that it is possible to obtain information based on plenty of ancient peptides recovered from subsuperficial enamel of fossil teeth from South American Pleistocene. The quality of the data suggests that peptides are likely the best preserved biomolecules under certain harsh environmental conditions. The recovery procedure only lasted 20 s and was minimally destructive to the fossils. This opens a myriad of new possibilities for the study of the past.
Subject(s)
Fossils , Peptides , Animals , Dental Enamel , Phylogeny , RatsABSTRACT
Protease activity has been associated with pathological processes that can lead to cancer development and progression. However, understanding the pathological unbalance in proteolysis is challenging because changes can occur simultaneously at protease, their inhibitor, and substrate levels. Here, we present a pipeline that combines peptidomics, proteomics, and peptidase predictions for studying proteolytic events in the saliva of 79 patients and their association with oral squamous cell carcinoma (OSCC) prognosis. Our findings revealed differences in the saliva peptidome of patients with (pN+) or without (pN0) lymph-node metastasis and delivered a panel of ten endogenous peptides correlated with poor prognostic factors plus five molecules able to classify pN0 and pN+ patients (area under the receiver operating characteristic curve > 0.85). In addition, endopeptidases and exopeptidases putatively implicated in the processing of differential peptides were investigated using cancer tissue gene expression data from public repositories, reinforcing their association with poorer survival rates and prognosis in oral cancer. The dynamics of the OSCC-related proteolysis were further explored via the proteomic profiling of saliva. This revealed that peptidase/endopeptidase inhibitors exhibited reduced levels in the saliva of pN+ patients, as confirmed by selected reaction monitoring-mass spectrometry, while minor changes were detected in the level of saliva proteases. Taken together, our results indicated that proteolytic activity is accentuated in the saliva of patients with OSCC and lymph-node metastasis and, at least in part, is modulated by reduced levels of salivary peptidase inhibitors. Therefore, this integrated pipeline provided better comprehension and discovery of molecular features with implications in the oral cancer metastasis prognosis.
Subject(s)
Carcinoma, Squamous Cell/metabolism , Lymphatic Metastasis , Mouth Neoplasms/metabolism , Peptide Hydrolases/metabolism , Peptides/analysis , Saliva/chemistry , Carcinoma, Squamous Cell/pathology , Humans , Mouth Neoplasms/pathology , Peptides/metabolism , Prognosis , ProteomicsABSTRACT
The radiation-attenuated cercarial vaccine remains the gold standard for the induction of protective immunity against Schistosoma mansoni. Furthermore, the protection can be passively transferred to naïve recipient mice from multiply vaccinated donors, especially IFNgR KO mice. We have used such sera versus day 28 infection serum, to screen peptide arrays and identify likely epitopes that mediate the protection. The arrays encompassed 55 secreted or exposed proteins from the alimentary tract and tegument, the principal interfaces with the host bloodstream. The proteins were printed onto glass slides as overlapping 15mer peptides, reacted with primary and secondary antibodies, and reactive regions detected using an Agilent array scanner. Pep Slide Analyzer software provided a numerical value above background for each peptide from which an aggregate score could be derived for a putative epitope. The reactive regions of 26 proteins were mapped onto crystal structures using the CCP4 molecular graphics, to aid selection of peptides with the greatest accessibility and reactivity, prioritizing vaccine over infection serum. A further eight MEG proteins were mapped to regions conserved between family members. The result is a list of priority peptides from 44 proteins for further investigation in multiepitope vaccine constructs and as targets of monoclonal antibodies.
ABSTRACT
Drought stress is an important abiotic factor limiting common bean yield, with great impact on the production worldwide. Understanding the genetic basis regulating beans' yield and seed weight (SW) is a fundamental prerequisite for the development of superior cultivars. The main objectives of this work were to conduct genome-wide marker discovery by genotyping a Mesoamerican panel of common bean germplasm, containing cultivated and landrace accessions of broad origin, followed by the identification of genomic regions associated with productivity under two water regimes using different genome-wide association study (GWAS) approaches. A total of 11,870 markers were genotyped for the 339 genotypes, of which 3,213 were SilicoDArT and 8,657 SNPs derived from DArT and CaptureSeq. The estimated linkage disequilibrium extension, corrected for structure and relatedness (r 2 sv ), was 98.63 and 124.18 kb for landraces and breeding lines, respectively. Germplasm was structured into landraces and lines/cultivars. We carried out GWASs for 100-SW and yield in field environments with and without water stress for 3 consecutive years, using single-, segment-, and gene-based models. Higher number of associations at high stringency was identified for the SW trait under irrigation, totaling â¼185 QTLs for both single- and segment-based, whereas gene-based GWASs showed â¼220 genomic regions containing â¼650 genes. For SW under drought, 18 QTLs were identified for single- and segment-based and 35 genes by gene-based GWASs. For yield, under irrigation, 25 associations were identified, whereas under drought the total was 10 using both approaches. In addition to the consistent associations detected across experiments, these GWAS approaches provided important complementary QTL information (â¼221 QTLs; 650 genes; r 2 from 0.01% to 32%). Several QTLs were mined within or near candidate genes playing significant role in productivity, providing better understanding of the genetic mechanisms underlying these traits and making available molecular tools to be used in marker-assisted breeding. The findings also allowed the identification of genetic material (germplasm) with better yield performance under drought, promising to a common bean breeding program. Finally, the availability of this highly diverse Mesoamerican panel is of great scientific value for the analysis of any relevant traits in common bean.
ABSTRACT
The activity of Thioredoxin-1 (Trx-1) is adjusted by the balance of its monomeric, active and its dimeric, inactive state. The regulation of this balance is not completely understood. We have previously shown that the cytoplasmic domain of the transmembrane protein A Disintegrin And Metalloprotease 17 (ADAM17cyto) binds to Thioredoxin-1 (Trx-1) and the destabilization of this interaction favors the dimeric state of Trx-1. Here, we investigate whether ADAM17 plays a role in the conformation and activation of Trx-1. We found that disrupting the interacting interface with Trx-1 by a site-directed mutagenesis in ADAM17 (ADAM17cytoF730A) caused a decrease of Trx-1 reductive capacity and activity. Moreover, we observed that ADAM17 overexpressing cells favor the monomeric state of Trx-1 while knockdown cells do not. As a result, there is a decrease of cell oxidant levels and ADAM17 sheddase activity and an increase in the reduced cysteine-containing peptides in intracellular proteins in ADAM17cyto overexpressing cells. A mechanistic explanation that ADAM17cyto favors the monomeric, active state of Trx-1 is the formation of a disulfide bond between Cys824 at the C-terminal of ADAM17cyto with the Cys73 of Trx-1, which is involved in the dimerization site of Trx-1. In summary, we propose that ADAM17 is able to modulate Trx-1 conformation affecting its activity and intracellular redox state, bringing up a novel possibility for positive regulation of thiol isomerase activity in the cell by mammalian metalloproteinases.
Subject(s)
ADAM17 Protein , Cysteine , Thioredoxins , Cysteine/metabolism , HEK293 Cells , Humans , Molecular Conformation , Oxidation-Reduction , Sulfhydryl Compounds , Thioredoxins/genetics , Thioredoxins/metabolismABSTRACT
The Asian invasive species Limnoperna fortunei (Dunker, 1857), known as the golden mussel, causes great economic and environmental damage due to its fixative capacity and accelerated proliferation. Molecular studies for the control of larval and adult forms are of great economic, scientific and technological interest. Here, we first report on the compositional analysis of the L. fortunei proteome obtained through shotgun analysis using LC-MS/MS. Among those 2790 proteins identified, many of them related to secretory processes and membrane receptors. Our second approach consisted in exposing the mollusc to the molluscicide niclosamide to evaluate the induced proteomic alterations. Exposure to niclosamide at 0.25 mg/L for 24 h resulted in a pronounced differential abundance of proteins when compared to those obtained when exposure was reduced to 4 h at 2.3 mg/L. In total, 342 proteins were found differentially expressed in the responsive individuals as revealed by label-free quantitative proteomics. Regarding the affected cell processes were: cell division and differentiation, cytoskeletal organization and compartment acidification (upregulated), and energy metabolism (downregulated). Our findings constitute the first inventory of the expressed proteome of the golden mussel and have the potential to contribute with a more rational proposition of molecular targets for control and monitoring of this species. SIGNIFICANCE: With the recent availability of transcriptomic and genomic data applied to L. fortunei the timing is right to interrogate its putative gene repertoire using proteomic techniques. These have the potential to validate the existence of the predicted genes, infer their relative abundance and quantify their levels as a response to environmental stressors or various agents. Here we provided an inventory of the golden mussel proteome and evaluated its response to the molluscicide niclosamide. The obtained results open new avenues for intervention aimed at its control or elimination, particularly by targeting the various cellular processes that were uncovered.
Subject(s)
Niclosamide , Proteome , Animals , Chromatography, Liquid , Proteomics , Tandem Mass SpectrometryABSTRACT
Schistosomes are blood-dwelling helminth parasites that cause schistosomiasis, a debilitating disease resulting in inflammation and, in extreme cases, multiple organ damage. Major challenges to control the transmission persist, and the discovery of protective antigens remains of critical importance for vaccine development. Rhesus macaques can self-cure following schistosome infection, generating antibodies that target proteins from the tegument, gut, and esophagus, the last of which is the least investigated. We developed a dissection technique that permitted increased sensitivity in a comparative proteomics profiling of schistosome esophagus and gut. Proteome analysis of the male schistosome esophagus identified 13 proteins encoded by microexon genes (MEGs), 11 of which were uniquely located in the esophageal glands. Based on this and transcriptome information, a QconCAT was designed for the absolute quantification of selected targets. MEGs 12, 4.2, and 4.1 and venom allergen-like protein 7 were the most abundant, spanning over 245 million to 6 million copies per cell, while aspartyl protease, palmitoyl thioesterase, and galactosyl transferase were present at <1 million copies. Antigenic variation by alternative splicing of MEG proteins was confirmed together with a specialized machinery for protein glycosylation/secretion in the esophagus. Moreover, some gastrodermal secretions were highly enriched in the gut, while others were more uniformly distributed throughout the parasite, potentially indicating lysosomal activity. Collectively, our findings provide a more rational, better-oriented selection of schistosome vaccine candidates in the context of a proven model of protective immunity.