ABSTRACT
Since the advent of sequencing techniques and due to their continuous evolution, it has become easier and less expensive to obtain the complete genome sequence of any organism. Nevertheless, to elucidate all biological processes governing organism development, quality annotation is essential. In genome annotation, predicting gene structure is one of the most important and captivating challenges for computational biology. This aspect of annotation requires continual optimization, particularly for genomes as unusual as those of microsporidia. Indeed, this group of fungal-related parasites exhibits specific features (highly reduced gene sizes, sequences with high rate of evolution) linked to their evolution as intracellular parasites, requiring the implementation of specific annotation approaches to consider all these features. This review aimed to outline these characteristics and to assess the increasingly efficient approaches and tools that have enhanced the accuracy of gene prediction for microsporidia, both in terms of sensitivity and specificity. Subsequently, a final part will be dedicated to postgenomic approaches aimed at reinforcing the annotation data generated by prediction software. These approaches include the characterization of other understudied genes, such as those encoding regulatory noncoding RNAs or very small proteins, which also play crucial roles in the life cycle of these microorganisms.
ABSTRACT
With nearly 1700 species, Microsporidia represent a group of obligate intracellular eukaryotes with veterinary, economic and medical impacts. To help understand the biological functions of these microorganisms, complete genome sequencing is routinely used. Nevertheless, the proper prediction of their gene catalogue is challenging due to their taxon-specific evolutionary features. As innovative genome annotation strategies are needed to obtain a representative snapshot of the overall lifestyle of these parasites, the MicroAnnot tool, a dedicated workflow for microsporidian sequence annotation using data from curated databases of accurately annotated microsporidian genes, has been developed. Furthermore, specific modules have been implemented to perform small gene (<300 bp) and transposable element identification. Finally, functional annotation was performed using the signature-based InterProScan software. MicroAnnot's accuracy has been verified by the re-annotation of four microsporidian genomes for which structural annotation had previously been validated. With its comparative approach and transcriptional signal identification method, MicroAnnot provides an accurate prediction of translation initiation sites, an efficient identification of transposable elements, as well as high specificity and sensitivity for microsporidian genes, including those under 300 bp.
Subject(s)
Microsporidia , Microsporidia/genetics , Workflow , Biological Evolution , DNA Transposable Elements/genetics , Databases, FactualABSTRACT
The extracellular matrix (ECM) is a three-dimensional set of proteins that binds tissues and defines their biomechanical properties. Among the ECM components known to be involved in beef sensory qualities, authors have often studied fibrillar collagens but also, although less often, proteoglycans and some glycoproteins. The ECM contains many other proteins. Our hypothesis is that to deepen the role of ECM proteins in beef qualities and to identify new ones among the vast amount of data generated by high throughput methods, it is necessary to have a list of proteins of this matrix to refer to for the bovine species. We have therefore defined the Bos taurus matrisome known as the set of genes encoding ECM (core matrisome proteins and matrisome-associated proteins). We have used orthology, as a reference method, and a bioinformatic approach based on a computational pipeline previously published for Homo sapiens, Mus musculus and Danio rerio for the definition of their respective matrisome. We have reported here that the Bos taurus matrisome is composed of 1022 genes that we have classified according to the different matrisome categories. This list is the only matrisome of a livestock species to be defined to date. SIGNIFICANCE: In this study, we provide the first definition of matrisome of a livestock species, the Bos taurus. We believe that the Bos taurus matrisome will be of great interest for several reasons. It comes as a complement to the matrisomes of several other species such as Homo sapiens, Mus musculus, Danio rerio, Drosophila melanogaster and Caenorabditis elegans previously defined by other authors. It could be used to identify matrisome molecules among the vast amount of data generated by the high throughput methods. It thus can be used in addition to the other matrisomes as a model by the scientific community to study cell behavior and mechanotransduction and could lead to the identification of novel biomarkers for several diseases and cancers in which ECM is involved. Moreover, in the domain of studies on livestock, the dataset that we have provided here can be used in the context of product quality studies, especially meat quality, but also, for example, for lactation studies.
Subject(s)
Extracellular Matrix Proteins , Zebrafish , Mice , Female , Cattle , Animals , Extracellular Matrix Proteins/metabolism , Zebrafish/metabolism , Drosophila melanogaster/metabolism , Mechanotransduction, Cellular , Extracellular Matrix/metabolism , MeatABSTRACT
Metabolic syndrome (MetS) is a complex condition encompassing a constellation of cardiometabolic abnormalities. Oxylipins are a superfamily of lipid mediators regulating many cardiometabolic functions. Plasma oxylipin signature could provide a new clinical tool to enhance the phenotyping of MetS pathophysiology. A high-throughput validated mass spectrometry method, allowing for the quantitative profiling of over 130 oxylipins, was applied to identify and validate the oxylipin signature of MetS in two independent nested case/control studies involving 476 participants. We identified an oxylipin signature of MetS (coined OxyScore), including 23 oxylipins and having high performances in classification and replicability (cross-validated AUCROC of 89%, 95% CI: 85-93% and 78%, 95% CI: 72-85% in the Discovery and Replication studies, respectively). Correlation analysis and comparison with a classification model incorporating the MetS criteria showed that the oxylipin signature brings consistent and complementary information to the clinical criteria. Being linked with the regulation of various biological processes, the candidate oxylipins provide an integrative phenotyping of MetS regarding the activation and/or negative feedback regulation of crucial molecular pathways. This may help identify patients at higher risk of cardiometabolic diseases. The oxylipin signature of patients with metabolic syndrome enhances MetS phenotyping and may ultimately help to better stratify the risk of cardiometabolic diseases.
Subject(s)
Cardiovascular Diseases , Metabolic Syndrome , Case-Control Studies , Humans , Oxylipins/analysisABSTRACT
In meat-producing animals, preslaughter operations (e.g., transportation, mixing unfamiliar animals, food and water deprivation) may be a source of stress with detrimental effects on meat quality. The objective of this work was to study the effect of emotional and physical stress by comparing the transcriptomes of two muscles (M. longissimus thoracis, LT and M. semitendinosus, ST) in Normand cows exposed to stress (n = 16) vs. cows handled with limited stress (n = 16). Using a microarray, we showed that exposure to stress resulted in differentially expressed genes (DEGs) in both muscles (62 DEGs in LT and 32 DEGs in ST, of which eight were common transcription factors (TFs)). Promoter analysis of the DEGs showed that 25 cis transcriptional modules were overrepresented, of which nine were detected in both muscles. Molecular interaction networks of the DEGs targeted by the most represented cis modules helped identify common regulators and common targets involved in the response to stress. They provided elements showing that the transcriptional response to stress is likely to (i) be controlled by regulators of energy metabolism, factors involved in the response to hypoxia, and inflammatory cytokines; and (ii) initiate metabolic processes, angiogenesis, corticosteroid response, immune system processes, and satellite cell activation/quiescence. The results of this study demonstrate that exposure to stress induced a core response to stress in both muscles, including changes in the expression of TFs. These factors could relay the physiological adaptive response of cattle muscles to cope with emotional and physical stress. The study provides information to further understand the consequences of these molecular processes on meat quality and find strategies to attenuate them.
Subject(s)
Gene Expression Profiling , Gene Regulatory Networks , Female , Cattle , Animals , Gene Regulatory Networks/genetics , Gene Expression Profiling/veterinary , Muscles , Transcriptome/genetics , MeatABSTRACT
Infertility represents a growing burden worldwide, with one in seven couples presenting difficulties conceiving. Among these, 10-15% of the men have idiopathic infertility that does not correlate with any defect in the classical sperm parameters measured. In the present study, we used a mouse model to investigate the effects of maternal undernutrition on fertility in male progeny. Our results indicate that mothers fed on a low-protein diet during gestation and lactation produce male offspring with normal sperm morphology, concentration, and motility but exhibiting an overall decrease of fertility when they reach adulthood. Particularly, in contrast to control, sperm from these offspring show a remarkable lower capacity to fertilize oocytes when copulation occurs early in the estrus cycle relative to ovulation, due to an altered sperm capacitation. Our data demonstrate for the first time that maternal nutritional stress can have long-term consequences on the reproductive health of male progeny by affecting sperm physiology, especially capacitation, with no observable impact on spermatogenesis and classical quantitative and qualitative sperm parameters. Moreover, our experimental model could be of major interest to study, explain, and ultimately treat certain categories of infertilities.
Subject(s)
Infertility, Male , Malnutrition , Adult , Animals , Female , Fertility , Humans , Infertility, Male/etiology , Lactation , Male , Malnutrition/complications , Mice , Pregnancy , Sperm Capacitation , Sperm Motility , Spermatozoa/physiologyABSTRACT
In order to automatically process qPCR raw data, we present the tool "Do my qPCR calculation". We offer a website to automatically calculate the data normalization and represent the different samples graphically in an Excel file. This tool is also available on Github for installation and local use with or without web interface.
ABSTRACT
Genomics experiments are widely acknowledged to produce a huge amount of data to be analysed. The challenge is to extract meaningful biological context for proteins or genes which is currently difficult because of the lack of an integrative workflow that hinders the efficiency and the robustness of data mining performed by biologists working on ruminants. Thus, we designed ProteINSIDE, a free web service (www.proteinside.org) that (I) provides an overview of the biological information stored in public databases or provided by annotations according to the Gene Ontology, (II) predicts proteins that are secreted to search for proteins that mediate signalisation between cells or tissues, and (III) analyses protein-protein interactions to identify proteins contributing to a process or to visualize functional pathways. Using lists of proteins or genes as a unique input, ProteINSIDE is an original all-in-one tool that merges data from these searches to present a fast overview and integrative analysis of genomic and proteomic data from Bovine, Ovine, Caprine, Human, Rat, and Murine species. ProteINSIDE was bench tested with 1000 proteins identifiers from each species by comparison with DAVID, BioMyn, AgBase, PrediSi, and Phobius. Compared to DAVID or BioMyn, identifications and annotations provided by ProteINSIDE were similar from monogastric proteins but more numerous and relevant for ruminants proteins. ProteINSIDE, thanks to SignalP, listed less proteins potentially secreted with a signal peptide than PrediSi and Phobius, in agreement with the low false positive rate of SignalP. In addition ProteINSIDE is the only resource that predicts proteins secreted by cellular processes that do not involve a signal peptide. Lastly, we reported the usefulness of ProteINSIDE to bring new biological hypotheses of research from proteomics data: the biological meaning of the uptake of adiponectin by the foetal muscle and a role for autophagy during ontogenesis of adipose and muscle tissues.
Subject(s)
Adipose Tissue/metabolism , Databases, Protein , Muscle, Skeletal/metabolism , Proteome/metabolism , Proteomics/methods , Animals , Cattle , Humans , Mice , Rats , Sheep , SoftwareABSTRACT
BACKGROUND: Metagenomics, based on culture-independent sequencing, is a well-fitted approach to provide insights into the composition, structure and dynamics of environmental viral communities. Following recent advances in sequencing technologies, new challenges arise for existing bioinformatic tools dedicated to viral metagenome (i.e. virome) analysis as (i) the number of viromes is rapidly growing and (ii) large genomic fragments can now be obtained by assembling the huge amount of sequence data generated for each metagenome. RESULTS: To face these challenges, a new version of Metavir was developed. First, all Metavir tools have been adapted to support comparative analysis of viromes in order to improve the analysis of multiple datasets. In addition to the sequence comparison previously provided, viromes can now be compared through their k-mer frequencies, their taxonomic compositions, recruitment plots and phylogenetic trees containing sequences from different datasets. Second, a new section has been specifically designed to handle assembled viromes made of thousands of large genomic fragments (i.e. contigs). This section includes an annotation pipeline for uploaded viral contigs (gene prediction, similarity search against reference viral genomes and protein domains) and an extensive comparison between contigs and reference genomes. Contigs and their annotations can be explored on the website through specifically developed dynamic genomic maps and interactive networks. CONCLUSIONS: The new features of Metavir 2 allow users to explore and analyze viromes composed of raw reads or assembled fragments through a set of adapted tools and a user-friendly interface.