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1.
Bioinformatics ; 40(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960861

RESUMO

MOTIVATION: The alignment of sequencing reads is a critical step in the characterization of ancient genomes. However, reference bias and spurious mappings pose a significant challenge, particularly as cutting-edge wet lab methods generate datasets that push the boundaries of alignment tools. Reference bias occurs when reference alleles are favoured over alternative alleles during mapping, whereas spurious mappings stem from either contamination or when endogenous reads fail to align to their correct position. Previous work has shown that these phenomena are correlated with read length but a more thorough investigation of reference bias and spurious mappings for ancient DNA has been lacking. Here, we use a range of empirical and simulated palaeogenomic datasets to investigate the impacts of mapping tools, quality thresholds, and reference genome on mismatch rates across read lengths. RESULTS: For these analyses, we introduce AMBER, a new bioinformatics tool for assessing the quality of ancient DNA mapping directly from BAM-files and informing on reference bias, read length cut-offs and reference selection. AMBER rapidly and simultaneously computes the sequence read mapping bias in the form of the mismatch rates per read length, cytosine deamination profiles at both CpG and non-CpG sites, fragment length distributions, and genomic breadth and depth of coverage. Using AMBER, we find that mapping algorithms and quality threshold choices dictate reference bias and rates of spurious alignment at different read lengths in a predictable manner, suggesting that optimized mapping parameters for each read length will be a key step in alleviating reference bias and spurious mappings. AVAILABILITY AND IMPLEMENTATION: AMBER is available for noncommercial use on GitHub (https://github.com/tvandervalk/AMBER.git). Scripts used to generate and analyse simulated datasets are available on Github (https://github.com/sdolenz/refbias_scripts).


Assuntos
DNA Antigo , Análise de Sequência de DNA , DNA Antigo/análise , Humanos , Análise de Sequência de DNA/métodos , Software , Animais , Alinhamento de Sequência/métodos , Biologia Computacional/métodos , Algoritmos
6.
Appl Microbiol Biotechnol ; 108(1): 415, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990377

RESUMO

Currently, the main α-amylase family GH13 has been divided into 47 subfamilies in CAZy, with new subfamilies regularly emerging. The present in silico study was performed to highlight the groups, represented by the maltogenic amylase from Thermotoga neapolitana and the α-amylase from Haloarcula japonica, which are worth of creating their own new GH13 subfamilies. This enlarges functional annotation and thus allows more precise prediction of the function of putative proteins. Interestingly, those two share certain sequence features, e.g. the highly conserved cysteine in the second conserved sequence region (CSR-II) directly preceding the catalytic nucleophile, or the well-preserved GQ character of the end of CSR-VII. On the other hand, the two groups bear also specific and highly conserved positions that distinguish them not only from each other but also from representatives of remaining GH13 subfamilies established so far. For the T. neapolitana maltogenic amylase group, it is the stretch of residues at the end of CSR-V highly conserved as L-[DN]. The H. japonica α-amylase group can be characterized by a highly conserved [WY]-[GA] sequence at the end of CSR-II. Other specific sequence features include an almost fully conserved aspartic acid located directly preceding the general acid/base in CSR-III or well-preserved glutamic acid in CSR-IV. The assumption that these two groups represent two mutually related, but simultaneously independent GH13 subfamilies has been supported by phylogenetic analysis as well as by comparison of tertiary structures. The main α-amylase family GH13 has thus been expanded by two novel subfamilies GH13_48 and GH13_49. KEY POINTS: • In silico analysis of two groups of family GH13 members with characterized representatives • Identification of certain common, but also some specific sequence features in seven CSRs • Creation of two novel subfamilies-GH13_48 and GH13_49 within the CAZy database.


Assuntos
Filogenia , alfa-Amilases , alfa-Amilases/genética , alfa-Amilases/metabolismo , alfa-Amilases/química , Sequência de Aminoácidos , Sequência Conservada , Alinhamento de Sequência
7.
Parasite ; 31: 39, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38995112

RESUMO

Echinococcus granulosus sensu lato is a platyhelminth parasite and the etiological cause of cystic echinococcosis (CE), a zoonotic and neglected disease that infects animals and humans worldwide. As a part of the biological arsenal of the parasite, cathepsin L proteases are a group of proteins that are believed to be essential for parasite penetration, immune evasion, and establishment in the tissues of the host. In this work, we have cloned and sequenced a new putative cathepsin L protease from Echinococcus canadensis (EcCLP1). The bioinformatic analysis suggests that EcCLP1 could be synthesized as a zymogen and activated after proteolytic cleavage. The multiple sequence alignment with other cathepsin proteases reveals important functional conserved features like a conserved active site, an N-linked glycosylation residue, a catalytic triad, an oxyanion hole, and three putative disulfide bonds. The phylogenetic analysis suggests that EcCLP1 could indeed be a cathepsin L cysteine protease from clade 1 as it grouped with cathepsins from other species in this clade. Modeling studies suggest that EcCLP1 has two domains forming a cleft where the active site is located and an occluding role for the propeptide. The transcriptomic analysis reveals different levels of cathepsin transcript expression along the different stages of the parasite life cycle. The whole-mount immunohistochemistry shows an interesting superficial punctate pattern of staining which suggests a secretory pattern of expression. The putative cathepsin L protease characterized here may represent an interesting tool for diagnostic purposes, vaccine design, or a new pharmacological target for antiparasitic intervention.


Title: Caractérisation moléculaire d'EcCLP1, une nouvelle protéase putative de type cathepsine L d'Echinococcus canadensis. Abstract: Echinococcus granulosus sensu lato est un Plathelminthe parasite et la cause étiologique de l'échinococcose kystique (EK), une maladie zoonotique et négligée qui infecte les animaux et les humains dans le monde entier. En tant que partie de l'arsenal biologique du parasite, les protéases de type cathepsine L sont un groupe de protéines considérées comme essentielles à la pénétration du parasite, l'évasion immunitaire et son établissement dans les tissus de l'hôte. Dans ce travail, nous avons cloné et séquencé une nouvelle protéase putative de type cathepsine L d'Echinococcus canadensis (EcCLP1). L'analyse bioinformatique suggère qu'EcCLP1 pourrait être synthétisée sous forme de zymogène et activée après clivage protéolytique. L'alignement de séquences multiples avec d'autres protéases de type cathepsine révèle d'importantes caractéristiques fonctionnelles conservées telles qu'un site actif conservé, un résidu de glycosylation lié à N, une triade catalytique, un trou oxyanion et trois liaisons disulfure putatives. L'analyse phylogénétique suggère qu'EcCLP1 pourrait en effet être une protéase de type cathepsine L du clade 1 car elle se regroupe avec les cathepsines d'autres espèces de ce clade. Les études de modélisation suggèrent qu'EcCLP1 possède deux domaines formant une fente où se trouve le site actif et un rôle d'occlusion pour le propeptide. L'analyse transcriptomique révèle différents niveaux d'expression du transcrit de la cathepsine au cours des différentes étapes du cycle de vie du parasite. L'immunohistochimie de montages entiers montre un intéressant motif de coloration ponctuée superficielle qui suggère un modèle d'expression sécrétoire. La protéase putative de type cathepsine L caractérisée ici peut représenter un outil intéressant à des fins de diagnostic, de conception de vaccins ou une nouvelle cible pharmacologique pour une intervention antiparasitaire.


Assuntos
Sequência de Aminoácidos , Catepsina L , Echinococcus , Filogenia , Animais , Catepsina L/genética , Echinococcus/enzimologia , Echinococcus/genética , Echinococcus/classificação , Alinhamento de Sequência , Clonagem Molecular , Proteínas de Helminto/genética , Proteínas de Helminto/química , Estágios do Ciclo de Vida , Equinococose/parasitologia , Domínio Catalítico , Perfilação da Expressão Gênica
8.
BMC Bioinformatics ; 25(1): 238, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003441

RESUMO

MOTIVATION: Alignment of reads to a reference genome sequence is one of the key steps in the analysis of human whole-genome sequencing data obtained through Next-generation sequencing (NGS) technologies. The quality of the subsequent steps of the analysis, such as the results of clinical interpretation of genetic variants or the results of a genome-wide association study, depends on the correct identification of the position of the read as a result of its alignment. The amount of human NGS whole-genome sequencing data is constantly growing. There are a number of human genome sequencing projects worldwide that have resulted in the creation of large-scale databases of genetic variants of sequenced human genomes. Such information about known genetic variants can be used to improve the quality of alignment at the read alignment stage when analysing sequencing data obtained for a new individual, for example, by creating a genomic graph. While existing methods for aligning reads to a linear reference genome have high alignment speed, methods for aligning reads to a genomic graph have greater accuracy in variable regions of the genome. The development of a read alignment method that takes into account known genetic variants in the linear reference sequence index allows combining the advantages of both sets of methods. RESULTS: In this paper, we present the minimap2_index_modifier tool, which enables the construction of a modified index of a reference genome using known single nucleotide variants and insertions/deletions (indels) specific to a given human population. The use of the modified minimap2 index improves variant calling quality without modifying the bioinformatics pipeline and without significant additional computational overhead. Using the PrecisionFDA Truth Challenge V2 benchmark data (for HG002 short-read data aligned to the GRCh38 linear reference (GCA_000001405.15) with parameters k = 27 and w = 14) it was demonstrated that the number of false negative genetic variants decreased by more than 9500, and the number of false positives decreased by more than 7000 when modifying the index with genetic variants from the Human Pangenome Reference Consortium.


Assuntos
Variação Genética , Genoma Humano , Sequenciamento Completo do Genoma , Humanos , Sequenciamento Completo do Genoma/métodos , Variação Genética/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Polimorfismo de Nucleotídeo Único/genética , Alinhamento de Sequência/métodos , Software , Algoritmos , Estudo de Associação Genômica Ampla/métodos
9.
HLA ; 104(1): e15600, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39015081

RESUMO

One nucleotide substitution in codon 30 of HLA-DRB4*01:03:01:01 results in a novel allele, HLA-DRB4*01:179.


Assuntos
Alelos , Éxons , Cadeias HLA-DRB4 , Teste de Histocompatibilidade , Humanos , Cadeias HLA-DRB4/genética , Códon , Sequência de Bases , Análise de Sequência de DNA , Alinhamento de Sequência
10.
Arch Insect Biochem Physiol ; 116(3): e22136, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39016052

RESUMO

H2A.Z, the most evolutionarily conserved variant of histone H2A, plays a pivotal role in chromatin remodeling and contributes significantly to gene transcription and genome stability. However, the role of H2A.Z in the silkworm (Bombyx mori) remains unclear. In this study, we cloned the BmH2A.Z from B. mori. The open reading frame of BmH2A.Z is 390 bp, encoding 129 amino acids, with a confirmed molecular weight of 13.4 kDa through prokaryotic expression analysis. Sequence analysis revealed that BmH2A.Z has a conserved H2A.Z domain and is closely related to the systemic evolution of other known H2A.Zs. The expression profile of BmH2A.Z at various developmental stages of the B. mori exhibited the highest expression level in the 1st instar, followed by the grain stage and the 2nd instar, and the lowest expression level in the moth. The highest transcript level of BmH2A.Z was observed in the head, with relatively lower levels detected in the blood than in the other tissues under consideration. In addition, the upregulation of BmH2A.Z resulted in the amplified expression of B. mori nucleopolyhedrovirus (BmNPV) genes, thus facilitating the proliferation of BmNPV. This study establishes a foundation for investigating the role of BmH2A.Z in B. mori and its participation in virus-host interactions.


Assuntos
Sequência de Aminoácidos , Bombyx , Clonagem Molecular , Histonas , Proteínas de Insetos , Animais , Bombyx/genética , Bombyx/metabolismo , Bombyx/virologia , Histonas/metabolismo , Histonas/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Larva/genética , Larva/metabolismo , Larva/crescimento & desenvolvimento , Filogenia , Nucleopoliedrovírus/genética , Alinhamento de Sequência
11.
J Comput Biol ; 31(7): 597-615, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38980804

RESUMO

Most sequence sketching methods work by selecting specific k-mers from sequences so that the similarity between two sequences can be estimated using only the sketches. Because estimating sequence similarity is much faster using sketches than using sequence alignment, sketching methods are used to reduce the computational requirements of computational biology software. Applications using sketches often rely on properties of the k-mer selection procedure to ensure that using a sketch does not degrade the quality of the results compared with using sequence alignment. Two important examples of such properties are locality and window guarantees, the latter of which ensures that no long region of the sequence goes unrepresented in the sketch. A sketching method with a window guarantee, implicitly or explicitly, corresponds to a decycling set of the de Bruijn graph, which is a set of unavoidable k-mers. Any long enough sequence, by definition, must contain a k-mer from any decycling set (hence, the unavoidable property). Conversely, a decycling set also defines a sketching method by choosing the k-mers from the set as representatives. Although current methods use one of a small number of sketching method families, the space of decycling sets is much larger and largely unexplored. Finding decycling sets with desirable characteristics (e.g., small remaining path length) is a promising approach to discovering new sketching methods with improved performance (e.g., with small window guarantee). The Minimum Decycling Sets (MDSs) are of particular interest because of their minimum size. Only two algorithms, by Mykkeltveit and Champarnaud, are previously known to generate two particular MDSs, although there are typically a vast number of alternative MDSs. We provide a simple method to enumerate MDSs. This method allows one to explore the space of MDSs and to find MDSs optimized for desirable properties. We give evidence that the Mykkeltveit sets are close to optimal regarding one particular property, the remaining path length. A number of conjectures and computational and theoretical evidence to support them are presented. Code available at https://github.com/Kingsford-Group/mdsscope.


Assuntos
Algoritmos , Biologia Computacional , Software , Biologia Computacional/métodos , Alinhamento de Sequência/métodos , Humanos , Análise de Sequência de DNA/métodos
12.
Sci Rep ; 14(1): 15145, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956134

RESUMO

Hepatitis C virus (HCV) is a plus-stranded RNA virus that often chronically infects liver hepatocytes and causes liver cirrhosis and cancer. These viruses replicate their genomes employing error-prone replicases. Thereby, they routinely generate a large 'cloud' of RNA genomes (quasispecies) which-by trial and error-comprehensively explore the sequence space available for functional RNA genomes that maintain the ability for efficient replication and immune escape. In this context, it is important to identify which RNA secondary structures in the sequence space of the HCV genome are conserved, likely due to functional requirements. Here, we provide the first genome-wide multiple sequence alignment (MSA) with the prediction of RNA secondary structures throughout all representative full-length HCV genomes. We selected 57 representative genomes by clustering all complete HCV genomes from the BV-BRC database based on k-mer distributions and dimension reduction and adding RefSeq sequences. We include annotations of previously recognized features for easy comparison to other studies. Our results indicate that mainly the core coding region, the C-terminal NS5A region, and the NS5B region contain secondary structure elements that are conserved beyond coding sequence requirements, indicating functionality on the RNA level. In contrast, the genome regions in between contain less highly conserved structures. The results provide a complete description of all conserved RNA secondary structures and make clear that functionally important RNA secondary structures are present in certain HCV genome regions but are largely absent from other regions. Full-genome alignments of all branches of Hepacivirus C are provided in the supplement.


Assuntos
Sequência Conservada , Genoma Viral , Hepacivirus , Conformação de Ácido Nucleico , RNA Viral , Hepacivirus/genética , RNA Viral/genética , RNA Viral/química , Humanos , Alinhamento de Sequência , Hepatite C/virologia , Hepatite C/genética
13.
Fish Shellfish Immunol ; 151: 109734, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38950759

RESUMO

Toll-like receptors (TLRs) are pattern recognition receptors that trigger host immune responses against various pathogens by detecting evolutionarily conserved pathogen-associated molecular patterns (PAMPs). TLR21 is a member of the Toll-like receptor family, and emerging data suggest that it recognises unmethylated CpG DNA and is considered a functional homologue of mammalian TLR9. However, little is known regarding the role of TLR21 in the fish immune response. In the present study, we isolated the cDNA sequence of TLR21 from the largemouth bass (Micropterus salmoides) and termed it MsTLR21. The MsTLR21 gene contained an open reading frame (ORF) of 2931 bp and encodes a polypeptide of 976 amino acids. The predicted MsTLR21 protein has two conserved domains, a conserved leucine-rich repeats (LRR) domain and a C-terminal Toll-interleukin (IL) receptor (TIR) domain, similar to those of other fish and mammals. In healthy largemouth bass, the TLR21 transcript was broadly expressed in all the examined tissues, with the highest expression levels in the gills. After challenge with Nocardia seriolae and polyinosinic polycytidylic acid (Poly[I:C]), the expression of TLR21 mRNA was upregulated or downregulated in all tissues tested. Overexpression of TLR21 in 293T cells showed that it has a positive regulatory effect on nuclear factor-kappaB (NF-κB) and interferons-ß (IFN-ß) activity. Subcellular localisation analysis showed that TLR21 was expressed in the cytoplasm. We performed pull-down assays and determined that TLR21 did not interact with myeloid differentiation primary response gene 88 (Myd88); however, it interacted with TIR domain-containing adaptor inducing interferon-ß (TRIF). Taken together, these findings suggest that MsTLR21 plays important roles in TLR/IL-1R signalling pathways and the immune response to pathogen invasion.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Sequência de Aminoácidos , Bass , Doenças dos Peixes , Proteínas de Peixes , NF-kappa B , Filogenia , Animais , Bass/imunologia , Bass/genética , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Proteínas de Peixes/química , NF-kappa B/genética , NF-kappa B/metabolismo , NF-kappa B/imunologia , Doenças dos Peixes/imunologia , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/imunologia , Proteínas Adaptadoras de Transporte Vesicular/química , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Transdução de Sinais/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Alinhamento de Sequência/veterinária , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/imunologia , Fator 88 de Diferenciação Mieloide/química , Perfilação da Expressão Gênica/veterinária , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Receptores Toll-Like/química , Receptores Toll-Like/metabolismo , Sequência de Bases
14.
Fish Shellfish Immunol ; 151: 109736, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38950760

RESUMO

RIPK1/TAK1 are important for programmed cell death, including liver death, necroptosis and apoptosis. However, there have been few published reports on the functions of RIPK1/TAK1 in invertebrates. In this study, full-length ChRIPK1 and ChTAK1 were cloned from C. hongkongensis through the rapid amplification of cDNA ends (RACE) technology. ChRIPK1 has almost no homology with human RIPK1 and lacks a kinase domain at the N-terminus but has a DD and RHIM domain. ChTAK1 is conserved throughout evolution. qRT‒PCR was used to analyze the mRNA expression patterns of ChRIPK1 in different tissues, developmental stages, and V. coralliilyticus-infected individuals, and both were highly expressed in the mantle and gills, while ChRIPK1 was upregulated in hemocytes and gills after V. coralliilyticus or S. aureus infection, which indicates that ChRIPK1 is involved in immune regulation. Fluorescence assays revealed that ChRIPK1 localized to the cytoplasm of HEK293T cells in a punctiform manner, but the colocalization of ChRIPK1 with ChTAK1 abolished the punctiform morphology. In the dual-luciferase reporter assay, both ChRIPK1 and ChRIPK1-RIHM activated the NF-κB signaling pathway in HEK293T cells, and ChTAK1 activated ChRIPK1 in the NF-κB signaling pathway. The apoptosis rate of the hemocytes was not affected by the necroptosis inhibitor Nec-1 but was significantly decreased, and ChRIPK1 expression was knocked down in the hemocytes of C. hongkongensis. These findings indicated that ChRIPK1 induces apoptosis but not necroptosis in oysters. This study provides a theoretical basis for further research on the molecular mechanism by which invertebrates regulate the programmed cell death of hemocytes in oysters.


Assuntos
Crassostrea , Necroptose , Filogenia , Transdução de Sinais , Animais , Crassostrea/genética , Crassostrea/imunologia , Necroptose/imunologia , Transdução de Sinais/imunologia , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Regulação da Expressão Gênica/imunologia , Alinhamento de Sequência/veterinária , Perfilação da Expressão Gênica/veterinária , Sequência de Aminoácidos , Imunidade Inata/genética , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/imunologia , Staphylococcus aureus/fisiologia , Dinoflagellida/fisiologia , Dinoflagellida/genética
15.
Fish Shellfish Immunol ; 151: 109745, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38960105

RESUMO

Iron homeostasis is vital for the host's defense against pathogenic invasion and the ferritinophagy is a crucial mechanism in maintaining intracellular iron homeostasis by facilitating the degradation and recycling of stored iron. The nuclear receptor coactivator 4 (NCOA4) serves as a ferritinophagy receptor, facilitating the binding and delivery of ferritin to the autophagosome and lysosome. However, NCOA4 of the sea cucumber Apostichopus japonicus (AjNCOA4) has not been reported until now. In this study, we identified and characterized AjNCOA4 in A. japonicus. This gene encodes a polypeptide containing 597 amino acids with an open reading frame of 1794 bp. The inferred amino acid sequence of AjNCOA4 comprises an ARA70 domain. Furthermore, a multiple sequence alignment demonstrated varying degrees of sequence homology between AjNCOA4 from A. japonicus and other NCOA4 orthologs. The phylogenetic tree of NCOA4 correlates with the established timeline of metazoan evolution. Expression analysis revealed that AjNCOA4 is expressed in all tested tissues, including the body wall, muscle, intestine, respiratory tree, and coelomocytes. Following challenge with Vibrio splendidus, the coelomocytes exhibited a significant increase in AjNCOA4 mRNA levels, peaking at 24 h. We successfully obtained recombinant AjNCOA4 protein through prokaryotic expression and prepared a specific polyclonal antibody. Immunofluorescence and co-immunoprecipitation experiments demonstrated an interaction between AjNCOA4 and AjFerritin in coelomocytes. RNA interference-mediated knockdown of AjNCOA4 expression resulted in elevated iron ion levels in coelomocytes. Bacterial stimulation enhanced ferritinophagy in coelomocytes, while knockdown of AjNCOA4 reduced the occurrence of ferritinophagy. These findings suggest that AjNCOA4 modulates ferritinophagy induced by V. splendidus in coelomocytes of A. japonicus.


Assuntos
Sequência de Aminoácidos , Ferritinas , Coativadores de Receptor Nuclear , Filogenia , Alinhamento de Sequência , Stichopus , Vibrio , Animais , Vibrio/fisiologia , Stichopus/imunologia , Stichopus/genética , Stichopus/microbiologia , Coativadores de Receptor Nuclear/genética , Coativadores de Receptor Nuclear/imunologia , Ferritinas/genética , Ferritinas/imunologia , Ferritinas/metabolismo , Imunidade Inata/genética , Regulação da Expressão Gênica/imunologia , Perfilação da Expressão Gênica , Autofagia , Sequência de Bases
16.
Fish Shellfish Immunol ; 151: 109743, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964433

RESUMO

Adenosine Deaminases Acting on RNA (ADARs) are evolutionarily conserved enzymes known to convert adenosine to inosine in double-stranded RNAs and participate in host-virus interactions. Conducting a meta-analysis of available transcriptome data, we identified and characterised eight ADAR transcripts in Chlamys farreri, a farmed marine scallop susceptible to Acute viral necrosis virus (AVNV) infections and mortality outbreaks. Accordingly, we identified six ADAR genes in the Zhikong scallop genome, revised previous gene annotations, and traced alternative splicing variants. In detail, each ADAR gene encodes a unique combination of functional domains, always including the Adenosine deaminase domain, RNA binding domains and, in one case, two copies of a Z-DNA binding domain. After phylogenetic analysis, five C. farreri ADARs clustered in the ADAR1 clade along with sequences from diverse animal phyla. Gene expression analysis indicated CF051320 as the most expressed ADAR, especially in the eye and male gonad. The other four ADAR1 genes and one ADAR2 gene exhibited variable expression levels, with CF105370 and CF051320 significantly increasing during early scallop development. ADAR-mediated single-base editing, evaluated across adult C. farreri tissues and developmental stages, was mainly detectable in intergenic regions (83 % and 85 %, respectively). Overall, the expression patterns of the six ADAR genes together with the editing and hyper-editing values computed on scallops RNA-seq samples support the adaptive value of ADAR1-mediated editing, particularly in the pre-settling larval stages.


Assuntos
Adenosina Desaminase , Pectinidae , Filogenia , Edição de RNA , Animais , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Pectinidae/genética , Pectinidae/imunologia , Imunidade Inata/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Sequência de Aminoácidos , Transcriptoma , Alinhamento de Sequência/veterinária
17.
Fish Shellfish Immunol ; 151: 109741, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964436

RESUMO

Decay-accelerating factor (DAF) is an essential member of the complement regulatory protein family that plays an important role in immune response and host homeostasis in mammals. However, the immune function of DAF has not been well characterized in bony fish. In this study, a complement regulatory protein named CiDAF was firstly characterized from Ctenopharyngodon idella and its potential roles were investigated in intestine following bacterial infection. Similar to mammalian DAFs, CiDAF has multiple complement control protein (CCP) functional domains, suggesting the evolutionary conservation of DAFs. CiDAF was broadly expressed in all tested tissues, with a relatively high expression level detected in the spleen and kidney. In vivo immune challenge experiments revealed that CiDAF strongly responded to bacterial pathogens (Aeromonas hydrophila and Aeromonas veronii) and PAMPs (lipopolysaccharide (LPS) or muramyl dipeptide (MDP)) challenges. In vitro RNAi experiments indicated that knockdown of CiDAF could upregulate the expression of complement genes (C4b, C5 and C7) and inflammatory cytokines (TNF-α, IL-1ß and IL-8). Moreover, 2000 ng/mL of CiDAF agonist progesterone effectively alleviated LPS- or MDP-induced intestinal inflammation by regulating expression of complement factors, TLR/PepT1 pathway genes and inflammatory cytokines. Overall, these findings revealed that CiDAF may act as a negative regulator of intestinal complement pathway and immune response to bacterial challenge in grass carp.


Assuntos
Carpas , Doenças dos Peixes , Proteínas de Peixes , Infecções por Bactérias Gram-Negativas , Imunidade Inata , Intestinos , Animais , Carpas/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Doenças dos Peixes/imunologia , Imunidade Inata/genética , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Intestinos/imunologia , Regulação da Expressão Gênica/imunologia , Filogenia , Perfilação da Expressão Gênica/veterinária , Aeromonas hydrophila/fisiologia , Sequência de Aminoácidos , Alinhamento de Sequência/veterinária , Proteínas do Sistema Complemento/imunologia
18.
Fish Shellfish Immunol ; 151: 109747, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38969154

RESUMO

The transforming growth factor beta-activated kinase 1 (TAK1)/c-Jun N-terminal kinase (JNK) axis is an essential MAPK upstream mediator and regulates immune signaling pathways. However, whether the TAK1/JNK axis harnesses the strength in regulation of signal transduction in early vertebrate adaptive immunity is unclear. In this study, by modeling on Nile tilapia (Oreochromis niloticus), we investigated the potential regulatory function of TAK1/JNK axis on lymphocyte-mediated adaptive immune response. Both OnTAK1 and OnJNK exhibited highly conserved sequences and structures relative to their counterparts in other vertebrates. Their mRNA was widely expressed in the immune-associated tissues, while phosphorylation levels in splenic lymphocytes were significantly enhanced on the 4th day post-infection by Edwardsiella piscicida. In addition, OnTAK1 and OnJNK were significantly up-regulated in transcriptional level after activation of lymphocytes in vitro by phorbol 12-myristate 13-acetate plus ionomycin (P + I) or PHA, accompanied by a predominant increase in phosphorylation level. More importantly, inhibition of OnTAK1 activity by specific inhibitor NG25 led to a significant decrease in the phosphorylation level of OnJNK. Furthermore, blocking the activity of OnJNK with specific inhibitor SP600125 resulted in a marked reduction in the expression of T-cell activation markers including IFN-γ, CD122, IL-2, and CD44 during PHA-induced T-cell activation. In summary, these findings indicated that the conserved TAK1/JNK axis in Nile tilapia was involved in adaptive immune responses by regulating the activation of lymphocytes. This study enriched the current knowledge of adaptive immunity in teleost and provided a new perspective for understanding the regulatory mechanism of fish immunity.


Assuntos
Imunidade Adaptativa , Ciclídeos , Doenças dos Peixes , Proteínas de Peixes , Ativação Linfocitária , MAP Quinase Quinase Quinases , Animais , Ciclídeos/imunologia , Ciclídeos/genética , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Doenças dos Peixes/imunologia , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/imunologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/veterinária , Edwardsiella/imunologia , Edwardsiella/fisiologia , Regulação da Expressão Gênica/imunologia , Transdução de Sinais/imunologia , Perfilação da Expressão Gênica/veterinária , Filogenia , Alinhamento de Sequência/veterinária , Sequência de Aminoácidos
19.
Mol Biol Evol ; 41(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38934805

RESUMO

Most algorithms that are used to predict the effects of variants rely on evolutionary conservation. However, a majority of such techniques compute evolutionary conservation by solely using the alignment of multiple sequences while overlooking the evolutionary context of substitution events. We had introduced PHACT, a scoring-based pathogenicity predictor for missense mutations that can leverage phylogenetic trees, in our previous study. By building on this foundation, we now propose PHACTboost, a gradient boosting tree-based classifier that combines PHACT scores with information from multiple sequence alignments, phylogenetic trees, and ancestral reconstruction. By learning from data, PHACTboost outperforms PHACT. Furthermore, the results of comprehensive experiments on carefully constructed sets of variants demonstrated that PHACTboost can outperform 40 prevalent pathogenicity predictors reported in the dbNSFP, including conventional tools, metapredictors, and deep learning-based approaches as well as more recent tools such as AlphaMissense, EVE, and CPT-1. The superiority of PHACTboost over these methods was particularly evident in case of hard variants for which different pathogenicity predictors offered conflicting results. We provide predictions of 215 million amino acid alterations over 20,191 proteins. PHACTboost is available at https://github.com/CompGenomeLab/PHACTboost. PHACTboost can improve our understanding of genetic diseases and facilitate more accurate diagnoses.


Assuntos
Mutação de Sentido Incorreto , Filogenia , Humanos , Software , Biologia Computacional/métodos , Algoritmos , Alinhamento de Sequência
20.
HLA ; 103(6): e15553, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38837619

RESUMO

HLA-C*06:364 differs from HLA-C*06:02:01:01 by a non-synonymous nucleotide substitution in exon 3.


Assuntos
Alelos , Éxons , Antígenos HLA-C , Humanos , Antígenos HLA-C/genética , Teste de Histocompatibilidade , Sequência de Bases , Análise de Sequência de DNA/métodos , Códon , Alinhamento de Sequência
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