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1.
Sci Rep ; 10(1): 14004, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32814791

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), a novel evolutionary divergent RNA virus, is responsible for the present devastating COVID-19 pandemic. To explore the genomic signatures, we comprehensively analyzed 2,492 complete and/or near-complete genome sequences of SARS-CoV-2 strains reported from across the globe to the GISAID database up to 30 March 2020. Genome-wide annotations revealed 1,516 nucleotide-level variations at different positions throughout the entire genome of SARS-CoV-2. Moreover, nucleotide (nt) deletion analysis found twelve deletion sites throughout the genome other than previously reported deletions at coding sequence of the ORF8 (open reading frame), spike, and ORF7a proteins, specifically in polyprotein ORF1ab (n = 9), ORF10 (n = 1), and 3´-UTR (n = 2). Evidence from the systematic gene-level mutational and protein profile analyses revealed a large number of amino acid (aa) substitutions (n = 744), demonstrating the viral proteins heterogeneous. Notably, residues of receptor-binding domain (RBD) showing crucial interactions with angiotensin-converting enzyme 2 (ACE2) and cross-reacting neutralizing antibody were found to be conserved among the analyzed virus strains, except for replacement of lysine with arginine at 378th position of the cryptic epitope of a Shanghai isolate, hCoV-19/Shanghai/SH0007/2020 (EPI_ISL_416320). Furthermore, our results of the preliminary epidemiological data on SARS-CoV-2 infections revealed that frequency of aa mutations were relatively higher in the SARS-CoV-2 genome sequences of Europe (43.07%) followed by Asia (38.09%), and North America (29.64%) while case fatality rates remained higher in the European temperate countries, such as Italy, Spain, Netherlands, France, England and Belgium. Thus, the present method of genome annotation employed at this early pandemic stage could be a promising tool for monitoring and tracking the continuously evolving pandemic situation, the associated genetic variants, and their implications for the development of effective control and prophylaxis strategies.


Assuntos
Betacoronavirus/classificação , Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Heterogeneidade Genética , Genoma Viral/genética , Estudo de Associação Genômica Ampla/métodos , Saúde Global , Pneumonia Viral/epidemiologia , Sequência de Aminoácidos/genética , Anticorpos Neutralizantes/imunologia , Pareamento Incorreto de Bases , Sequência de Bases/genética , Clima , Infecções por Coronavirus/virologia , Humanos , Fases de Leitura Aberta/genética , Pandemias , Peptidil Dipeptidase A/metabolismo , Filogenia , Pneumonia Viral/virologia , Domínios Proteicos/genética , Domínios Proteicos/imunologia , Deleção de Sequência , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
2.
PLoS One ; 15(7): e0234550, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32663226

RESUMO

Chickpea has a profound nutritional and economic value in vegetarian society. Continuous decline in chickpea productivity is attributed to insufficient genetic variability and different environmental stresses. Chickpea like several other legumes is highly susceptible to terminal drought stress. Multiple genes control drought tolerance and ASR gene plays a key role in regulating different plant stresses. The present study describes the molecular characterization and functional role of Abscissic acid and stress ripening (ASR) gene from chickpea (Cicer arietinum) and the gene sequence identified was submitted to NCBI Genbank (MK937569). Molecular analysis using MUSCLE software proved that the ASR nucleotide sequences in different legumes show variations at various positions though ASR genes are conserved in chickpea with only few variations. Sequence similarity of ASR gene to chickpea putative ABA/WDS induced protein mRNA clearly indicated its potential involvement in drought tolerance. Physiological screening and qRT-PCR results demonstrated increased ASR gene expression under drought stress possibly enabled genotypes to perform better under stress. Conserved domain search, protein structure analysis, prediction and validation, network analysis using Phyre2, Swiss-PDB viewer, ProSA and STRING analysis established the role of hypothetical ASR protein NP_001351739.1 in mediating drought responses. NP_001351739.1 might have enhanced the ASR gene activity as a transcription factor regulating drought stress tolerance in chickpea. This study could be useful in identification of new ASR genes that play a major role in drought tolerance and also develop functional markers for chickpea improvement.


Assuntos
Cicer/genética , Regulação da Expressão Gênica de Plantas/genética , Estresse Fisiológico/genética , Ácido Abscísico/farmacologia , Adaptação Fisiológica/genética , Sequência de Bases/genética , Cicer/crescimento & desenvolvimento , Secas , Perfilação da Expressão Gênica/métodos , Genótipo , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Fatores de Transcrição/metabolismo
3.
PLoS Genet ; 16(7): e1008949, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32702045

RESUMO

In Paramecium tetraurelia, a large proportion of the germline genome is reproducibly removed from the somatic genome after sexual events via a process involving small (s)RNA-directed heterochromatin formation and DNA excision and repair. How germline limited DNA sequences are specifically recognized in the context of chromatin remains elusive. Here, we use a reverse genetics approach to identify factors involved in programmed genome rearrangements. We have identified a P. tetraurelia homolog of the highly conserved histone chaperone Spt16 subunit of the FACT complex, Spt16-1, and show its expression is developmentally regulated. A functional GFP-Spt16-1 fusion protein localized exclusively in the nuclei where genome rearrangements take place. Gene silencing of Spt16-1 showed it is required for the elimination of all germline-limited sequences, for the survival of sexual progeny, and for the accumulation of internal eliminated sequence (ies)RNAs, an sRNA population produced when elimination occurs. Normal accumulation of 25 nt scanRNAs and deposition of silent histone marks H3K9me3 and H3K27me3 indicated that Spt16-1 does not regulate the scanRNA-directed heterochromatin pathway involved in the early steps of DNA elimination. We further show that Spt16-1 is required for the correct nuclear localization of the PiggyMac (Pgm) endonuclease, which generates the DNA double-strand breaks required for DNA elimination. Thus, Spt16-1 is essential for Pgm function during programmed genome rearrangements. We propose a model in which Spt16-1 mediates interactions between the excision machinery and chromatin, facilitating endonuclease access to DNA cleavage sites during genome rearrangements.


Assuntos
Núcleo Celular/genética , Chaperonas de Histonas/genética , Paramecium/genética , Transposases/genética , Sequência de Bases/genética , Quebras de DNA de Cadeia Dupla , Clivagem do DNA , DNA de Protozoário/genética , Endonucleases , Rearranjo Gênico/genética , Genoma de Protozoário/genética , Paramecium/crescimento & desenvolvimento
4.
J Genet ; 992020.
Artigo em Inglês | MEDLINE | ID: mdl-32529988

RESUMO

Rice blast disease, caused by Magnaporthe oryzae, is one of the most importance diseases of rice production worldwide. The keyrole of defense mechanism to combat this fungus in rice follows the gene-for-gene concept, which a plant resistant (R) gene product recognizes a fungal avirulent (AVR) effector and triggers the hypersensitive response. However, the AVR genes have been shown to be rapidly evolving resulting in high level of genetic diversity. The aims of this study were to examine the nucleotide sequence variation of AVR-Pita1 gene in Thai rice blast isolates and to identify the severity of blast disease using isogenic line of Pita gene. Seventy-six rice blast isolates collected from different parts of Thailand were used. Gene specific primers for AVR-Pita1 gene coding sequence were designed and used for identifying the genetic diversity of AVR-Pita1 gene by PCR amplification and sequencing. The obtained sequences were analysed for genetic variation and genetic relationship. Our results revealed the association between the sequence variations of AVR-Pita1 and selective forces from Pita gene. This phenomenon demonstrated the coevolution between rice blast resistant gene in rice and avirulent gene in blast fungus. The information about variation and evolutionary mechanisms of AVR gene obtained from this study can be used in rice blast resistant breeding programme.


Assuntos
Ascomicetos/genética , Ascomicetos/isolamento & purificação , Sequência de Bases/genética , Variação Genética , Oryza , Filogenia , Reação em Cadeia da Polimerase , Fatores de Virulência
5.
mSphere ; 5(3)2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32581081

RESUMO

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has motivated an intensive analysis of its molecular epidemiology following its worldwide spread. To understand the early evolutionary events following its emergence, a data set of 985 complete SARS-CoV-2 sequences was assembled. Variants showed a mean of 5.5 to 9.5 nucleotide differences from each other, consistent with a midrange coronavirus substitution rate of 3 × 10-4 substitutions/site/year. Almost one-half of sequence changes were C→U transitions, with an 8-fold base frequency normalized directional asymmetry between C→U and U→C substitutions. Elevated ratios were observed in other recently emerged coronaviruses (SARS-CoV, Middle East respiratory syndrome [MERS]-CoV), and decreasing ratios were observed in other human coronaviruses (HCoV-NL63, -OC43, -229E, and -HKU1) proportionate to their increasing divergence. C→U transitions underpinned almost one-half of the amino acid differences between SARS-CoV-2 variants and occurred preferentially in both 5' U/A and 3' U/A flanking sequence contexts comparable to favored motifs of human APOBEC3 proteins. Marked base asymmetries observed in nonpandemic human coronaviruses (U ≫ A > G ≫ C) and low G+C contents may represent long-term effects of prolonged C→U hypermutation in their hosts. The evidence that much of sequence change in SARS-CoV-2 and other coronaviruses may be driven by a host APOBEC-like editing process has profound implications for understanding their short- and long-term evolution. Repeated cycles of mutation and reversion in favored mutational hot spots and the widespread occurrence of amino acid changes with no adaptive value for the virus represent a quite different paradigm of virus sequence change from neutral and Darwinian evolutionary frameworks and are not incorporated by standard models used in molecular epidemiology investigations.IMPORTANCE The wealth of accurately curated sequence data for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), its long genome, and its low substitution rate provides a relatively blank canvas with which to investigate effects of mutational and editing processes imposed by the host cell. The finding that a large proportion of sequence change in SARS-CoV-2 in the initial months of the pandemic comprised C→U mutations in a host APOBEC-like context provides evidence for a potent host-driven antiviral editing mechanism against coronaviruses more often associated with antiretroviral defense. In evolutionary terms, the contribution of biased, convergent, and context-dependent mutations to sequence change in SARS-CoV-2 is substantial, and these processes are not incorporated by standard models used in molecular epidemiology investigations.


Assuntos
Betacoronavirus/genética , Citosina/análise , Genoma Viral/genética , Polimorfismo de Nucleotídeo Único/genética , Uracila/análise , Composição de Bases/genética , Sequência de Bases/genética , Infecções por Coronavirus/patologia , Citidina Desaminase/genética , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Pandemias , Pneumonia Viral/patologia , Vírus da SARS/genética
6.
Sci Adv ; 6(25): eabb5813, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32596474

RESUMO

The COVID-19 outbreak has become a global health risk, and understanding the response of the host to the SARS-CoV-2 virus will help to combat the disease. RNA editing by host deaminases is an innate restriction process to counter virus infection, but it is not yet known whether this process operates against coronaviruses. Here, we analyze RNA sequences from bronchoalveolar lavage fluids obtained from coronavirus-infected patients. We identify nucleotide changes that may be signatures of RNA editing: adenosine-to-inosine changes from ADAR deaminases and cytosine-to-uracil changes from APOBEC deaminases. Mutational analysis of genomes from different strains of Coronaviridae from human hosts reveals mutational patterns consistent with those observed in the transcriptomic data. However, the reduced ADAR signature in these data raises the possibility that ADARs might be more effective than APOBECs in restricting viral propagation. Our results thus suggest that both APOBECs and ADARs are involved in coronavirus genome editing, a process that may shape the fate of both virus and patient.


Assuntos
Betacoronavirus/genética , Betacoronavirus/metabolismo , Infecções por Coronavirus/genética , Interações Hospedeiro-Patógeno/genética , Pneumonia Viral/genética , Edição de RNA/genética , Transcriptoma , Desaminases APOBEC/genética , Desaminases APOBEC/metabolismo , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Sequência de Bases/genética , Líquido da Lavagem Broncoalveolar/virologia , Infecções por Coronavirus/virologia , Genoma Viral/genética , Humanos , Taxa de Mutação , Nucleotídeos/genética , Nucleotídeos/metabolismo , Pandemias , Pneumonia Viral/virologia , RNA Viral/genética , Replicação Viral/genética
7.
Gene ; 755: 144883, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32565321

RESUMO

The anti-anti-sigma factor BldG has a pleiotropic function in Streptomyces coelicolor A3(2), regulating both morphological and physiological differentiation. Together with the anti-sigma factor UshX, it participates in a partner-switching activation of the sigma factor σH, which has a dual role in the osmotic stress response and morphological differentiation in S. coelicolor A3(2). In addition to UshX, BldG also interacts with the anti-sigma factor ApgA, although no target sigma factor has yet been identified. However, neither UshX nor ApgA phosphorylates BldG. This phosphorylation is provided by the anti-sigma factor RsfA, which is specific for the late developmental sigma factor σF. However, BldG is phosphorylated in the rsfA mutant, suggesting that some other anti-sigma factors containing HATPase_c kinase domain are capable to phosphorylate BldG in vivo. Bacterial two-hybrid system (BACTH) was therefore used to investigate the interactions of all suitable anti-sigma factors of S. coelicolor A3(2) with BldG. At least 15 anti-sigma factors were found to interact with BldG. These interactions were confirmed by native PAGE. In addition to RsfA, BldG is specifically phosphorylated on the conserved phosphorylation Ser57 residue by at least seven additional anti-sigma factors. However, only one of them, SCO7328, has been shown to interact with three sigma factors, σG, σK and σM. A mutant with deleted SCO7328 gene was prepared in S. coelicolor A3(2), however, no specific function of SCO7328 in growth, differentiation or stress response could be attributed to this anti-sigma factor. These results suggest that BldG is specifically phosphorylated by several anti-sigma factors and it plays a role in the regulation of several sigma factors in S. coelicolor A3(2). This suggests a complex regulation of the stress response and differentiation in S. coelicolor A3(2) through this pleiotropic anti-sigma factor.


Assuntos
Fator sigma/genética , Streptomyces coelicolor/imunologia , Streptomyces coelicolor/metabolismo , Sequência de Aminoácidos/genética , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Anti-Idiotípicos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases/genética , Regulação Bacteriana da Expressão Gênica/genética , Pleiotropia Genética/genética , Fosforilação/genética , Fosfotransferases/metabolismo , Regiões Promotoras Genéticas/genética , Fator sigma/imunologia , Fator sigma/metabolismo , Streptomyces/genética , Streptomyces coelicolor/genética , Transcrição Genética/genética
8.
Nucleic Acids Res ; 48(13): 7099-7118, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32558887

RESUMO

Nucleotide variants can cause functional changes by altering protein-RNA binding in various ways that are not easy to predict. This can affect processes such as splicing, nuclear shuttling, and stability of the transcript. Therefore, correct modeling of protein-RNA binding is critical when predicting the effects of sequence variations. Many RNA-binding proteins recognize a diverse set of motifs and binding is typically also dependent on the genomic context, making this task particularly challenging. Here, we present DeepCLIP, the first method for context-aware modeling and predicting protein binding to RNA nucleic acids using exclusively sequence data as input. We show that DeepCLIP outperforms existing methods for modeling RNA-protein binding. Importantly, we demonstrate that DeepCLIP predictions correlate with the functional outcomes of nucleotide variants in independent wet lab experiments. Furthermore, we show how DeepCLIP binding profiles can be used in the design of therapeutically relevant antisense oligonucleotides, and to uncover possible position-dependent regulation in a tissue-specific manner. DeepCLIP is freely available as a stand-alone application and as a webtool at http://deepclip.compbio.sdu.dk.


Assuntos
Simulação por Computador , Aprendizado Profundo , Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , Animais , Sequência de Bases/genética , Sítios de Ligação , Biologia Computacional , Humanos , Camundongos , Mutação , Conformação de Ácido Nucleico , Motivos de Nucleotídeos/genética , Ligação Proteica
9.
PLoS One ; 15(6): e0234903, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569288

RESUMO

The masked birch caterpillar, Drepana arcuata, provides an excellent opportunity to study mechanisms mediating developmental changes in social behaviour. Larvae transition from being social to solitary during the 3rd instar, concomitant with shifts in their use of acoustic communication. In this study we characterize the transcriptome of D. arcuata to initiate sociogenomic research of this lepidopteran insect. We assembled and annotated the combined larval transcriptome of "social" early and "solitary" late instars using next generation Illumina sequencing, and used this transcriptome to conduct differential gene expression analysis of the two behavioural phenotypes. A total of 211,012,294 reads generated by RNA sequencing were assembled into 231,348 transcripts and 116,079 unigenes for the functional annotation of the transcriptome. Expression analysis revealed 3300 transcripts that were differentially expressed between early and late instars, with a large proportion associated with development and metabolic processes. We independently validated differential expression patterns of selected transcripts using RT-qPCR. The expression profiles of social and solitary larvae revealed differentially expressed transcripts coding for gene products that have been previously reported to influence social behaviour in other insects (e.g. cGMP- and cAMP- dependent kinases, and bioamine receptors). This study provides the first transcriptomic resources for a lepidopteran species belonging to the superfamily Drepanoidea, and gives insight into genetic factors mediating grouping behaviour in insects.


Assuntos
Larva/genética , Lepidópteros/genética , Transcriptoma , Animais , Sequência de Bases/genética , Biologia do Desenvolvimento , Perfilação da Expressão Gênica/métodos , Genética Comportamental , Análise de Sequência de RNA/métodos
10.
Genet Sel Evol ; 52(1): 27, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460767

RESUMO

BACKGROUND: Distinct domestication events, adaptation to different climatic zones, and divergent selection in productive traits have shaped the genomic differences between taurine and indicine cattle. In this study, we assessed the impact of artificial selection and environmental adaptation by comparing whole-genome sequences from European taurine and Asian indicine breeds and from African cattle. Next, we studied the impact of divergent selection by exploiting predicted and experimental functional annotation of the bovine genome. RESULTS: We identified selective sweeps in beef cattle taurine and indicine populations, including a 430-kb selective sweep on indicine cattle chromosome 5 that is located between 47,670,001 and 48,100,000 bp and spans five genes, i.e. HELB, IRAK3, ENSBTAG00000026993, GRIP1 and part of HMGA2. Regions under selection in indicine cattle display significant enrichment for promoters and coding genes. At the nucleotide level, sites that show a strong divergence in allele frequency between European taurine and Asian indicine are enriched for the same functional categories. We identified nine single nucleotide polymorphisms (SNPs) in coding regions that are fixed for different alleles between subspecies, eight of which were located within the DNA helicase B (HELB) gene. By mining information from the 1000 Bull Genomes Project, we found that HELB carries mutations that are specific to indicine cattle but also found in taurine cattle, which are known to have been subject to indicine introgression from breeds, such as N'Dama, Anatolian Red, Marchigiana, Chianina, and Piedmontese. Based on in-house genome sequences, we proved that mutations in HELB segregate independently of the copy number variation HMGA2-CNV, which is located in the same region. CONCLUSIONS: Major genomic sequence differences between Bos taurus and Bos indicus are enriched for promoter and coding regions. We identified a 430-kb selective sweep in Asian indicine cattle located on chromosome 5, which carries SNPs that are fixed in indicine populations and located in the coding sequences of the HELB gene. HELB is involved in the response to DNA damage including exposure to ultra-violet light and is associated with reproductive traits and yearling weight in tropical cattle. Thus, HELB likely contributed to the adaptation of tropical cattle to their harsh environment.


Assuntos
Bovinos/genética , DNA Helicases/genética , Alelos , Animais , Sequência de Bases/genética , Cruzamento , Variações do Número de Cópias de DNA/genética , Dano ao DNA/genética , DNA Helicases/metabolismo , Domesticação , Feminino , Frequência do Gene/genética , Genótipo , Masculino , Mutação de Sentido Incorreto/genética , Fases de Leitura Aberta/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Seleção Genética/genética , Sequenciamento Completo do Genoma
11.
BMC Infect Dis ; 20(1): 319, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357839

RESUMO

BACKGROUND: Trichomoniasis resulting from Trichomonas vaginalis (T. vaginalis) has been considered as a commonly seen disease with the transmission way of sex. At present, the detection methods of T. vaginalis mainly include wet mount microscopy, culture, PCR, immunofluorescence and ELISA. However, all of these detection methods exist shortcomings. METHODS: In this study, a loop-mediated isothermal amplification (LAMP) assay that targeted the species-specific sequence of adhesion protein 65 (AP65) gene had been conducted to detect T. vaginalis. The optimum reaction system and conditions were optimized in this rapid detection method. RESULTS: The results of sensitivity analysis showed that the LAMP assay targeting the AP65 gene was 1000 times more sensitive than the nested PCR targeting the actin gene commonly used for detection of T. vaginalis, and the detecting limitation of the former was 10 trichomonad. Moreover, the amplification of the target gene AP65 by LAMP assay exhibited high specificity and the product was exclusively from T. vaginalis. The detection technique of LAMP did not exhibit cross-reactivity with the common pathogens of Trichinella spiralis, Toxoplasma gondii, Escherichia coli, Candida albicans, Staphylococcus aureus, Haemophilus. CONCLUSIONS: According to the present study, the LAMP assay with the target of AP65 gene, was suitable for the early diagnosis of T. vaginalis infections. Consequently, the LAMP assay was proposed by the current study as a point-of-care examination and an alternative molecular tool which exhibited the potential value in the treatment, control and prevention of trichomoniasis transmission and relevant complication.


Assuntos
Moléculas de Adesão Celular/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , Proteínas de Protozoários/genética , Tricomoníase/diagnóstico , Trichomonas vaginalis/genética , Sequência de Bases/genética , DNA de Protozoário/genética , Diagnóstico Precoce , Feminino , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Sensibilidade e Especificidade , Tricomoníase/parasitologia , Esfregaço Vaginal
12.
Arch Virol ; 165(8): 1887-1889, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32447622

RESUMO

This is the first description of the complete genome sequence of a new monopartite begomovirus isolated from tomato with symptoms of tomato (yellow) leaf curl disease collected in northwestern Namibia, which we provisionally name "tomato leaf curl Kunene virus". The DNA-A-like nucleotide sequence shares the highest nucleotide sequence identity (82.8%) with tobacco leaf curl Zimbabwe virus (ToLCZWV). Phylogenetic analysis confirmed its affiliation with Old World monopartite begomoviruses. The discovery of a new begomovirus in a vegetable plant in Namibia highlights the importance of maintaining epidemiological surveillance in southern Africa.


Assuntos
Begomovirus/genética , Lycopersicon esculentum/virologia , Sequência de Bases/genética , DNA Viral/genética , Genoma Viral/genética , Namíbia , Filogenia , Doenças das Plantas/virologia , Análise de Sequência de DNA/métodos
13.
Sci Rep ; 10(1): 7314, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32355260

RESUMO

Little research on coronaviruses has been conducted on wild animals in Africa. Here, we screened a wide range of wild animals collected in six provinces and five caves of Gabon between 2009 and 2015. We collected a total of 1867 animal samples (cave-dwelling bats, rodents, non-human primates and other wild animals). We explored the diversity of CoVs and determined the factors driving the infection of CoVs in wild animals. Based on a nested reverse transcription-polymerase chain reaction, only bats, belonging to the Hipposideros gigas (4/156), Hipposideros cf. ruber (13/262) and Miniopterus inflatus (1/249) species, were found infected with CoVs. We identified alphacoronaviruses in H. gigas and H. cf. ruber and betacoronaviruses in H. gigas. All Alphacoronavirus sequences grouped with Human coronavirus 229E (HCoV-229E). Ecological analyses revealed that CoV infection was significantly found in July and October in H. gigas and in October and November in H. cf ruber. The prevalence in the Faucon cave was significantly higher. Our findings suggest that insectivorous bats harbor potentially zoonotic CoVs; highlight a probable seasonality of the infection in cave-dwelling bats from the North-East of Gabon and pointed to an association between the disturbance of the bats' habitat by human activities and CoV infection.


Assuntos
Alphacoronavirus/genética , Betacoronavirus/genética , Cavernas , Quirópteros/virologia , Infecções por Coronavirus/epidemiologia , Variação Genética , Animais , Sequência de Bases/genética , Coronavirus Humano 229E/genética , Infecções por Coronavirus/virologia , Gabão/epidemiologia , Humanos , Insetívoros/virologia , Filogenia , Prevalência , Primatas/genética , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Roedores/genética , Estações do Ano
14.
BMC Infect Dis ; 20(1): 271, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264839

RESUMO

BACKGROUND: Hand, foot, and mouth disease (HFMD) is a common infectious disease occurring in children under 5 years of age worldwide, and Enterovirus A71 (EV-A71) and Coxsackievirus A16 (CVA-16) are identified as the predominant pathogens. In recent years, Coxsackievirus A6 (CVA-6) and Coxsackievirus A10 (CVA-10) have played more and more important role in a series of HFMD outbreaks. This study aimed to understand the epidemic characteristics associated with HFMD outbreak in Guangzhou, 2018. METHODS: The clinical and laboratory data of 1220 enterovirus-associated HFMD patients in 2018 were analysed in this study. Molecular diagnostic methods were performed to identify its serotypes. Phylogenetic analyses were depicted based on the complete VP1 gene. RESULTS: There were 21 enterovirus serotypes detected in Guangzhou in 2018. Three serotypes of enterovirus, CVA-6 (364/1220, 29.8%), CVA-10 (305/1220, 25.0%), and CVA-16 (397/1220, 32.5%), were identified as the causative pathogens and accounted for 87.3% among all 1220 HFMD patients. In different seasons, CVA-6 was the predominant pathogen of HFMD during autumn, and CVA-10 as well as CVA-16 were more prevalent in summer. Patients infected by CVA-6, CVA-10 or CVA-16 showed similar clinical features and laboratory characteristics, and the ratios of severe HFMD were 5.8, 5.9, and 1.5% in the three serotypes. Phylogenetic analyses of VP1 sequences showed that the CVA-6, CVA-10, and CVA-16 sequences belonged to the sub-genogroup E2, genogroup E, and genogroup B1, respectively. CONCLUSIONS: CVA-6, CVA-10, and CVA-16 were the predominant and co-circulated serotypes in Guangzhou China, 2018, which should be the new target for prevention and control of HFMD. Our findings provide useful information for diagnosis, treatment, and prevention of HFMD.


Assuntos
Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Epidemias , Doença de Mão, Pé e Boca/epidemiologia , Sequência de Bases/genética , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , China/epidemiologia , Feminino , Genótipo , Doença de Mão, Pé e Boca/virologia , Humanos , Lactente , Masculino , Filogenia , Prevalência , Estações do Ano , Sorogrupo
15.
BMC Infect Dis ; 20(1): 274, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264841

RESUMO

BACKGROUND: Human papillomaviruses (HPVs) have been divided into mucosal and cutaneous types according to their primary epithelial tissue tropism. However, recent studies showed the presence of several cutaneous types in mucosal lesions and healthy mucosa from different anatomical sites. METHODS: Here, the HPV prevalence and type-specific distribution were assessed in a variety of mucosal samples from 435 individuals using a combination of two established broad-spectrum primer systems: Gamma-PV PCR and CUT PCR. RESULTS: Overall HPV prevalence in anal canal swabs, cervical cancer biopsies, genital warts and oral swabs was 85, 47, 62 and 4%, respectively. In anal canal swabs, Alpha-PVs were most frequently found (59%), followed by Gamma- (37%) and Beta-PVs (4%). The prevalence and persistence of HPV infection in the anal canal of 226 individuals were further explored. Overall HPV, Gamma-PVs and multiple HPV infections were significantly higher in men vs. women (p = 0.034, p = 0.027 and p = 0.003, respectively); multiple HPV infections were more common in individuals ≤40 years (p = 0.05), and significantly higher prevalence of Gamma-PVs and multiple HPV infections was observed in HIV-1-positive vs. HIV-1-negative individuals (p = 0.003 and p = 0.04, respectively). Out of 21 patients with follow-up anal swabs, only one persistent infection with the same type (HPV58) was detected. CONCLUSIONS: Our findings suggest that Gamma-PVs (except species Gamma-6) are ubiquitous viruses with dual muco-cutaneous tissue tropism. Anal canal Gamma-PV infections may be associated with sexual behavior and the host immune status. This study expands the knowledge on Gamma-PVs' tissue tropism, providing valuable data on the characteristics of HPV infection in the anal canal.


Assuntos
Doenças do Ânus/complicações , Gammapapillomavirus/genética , Soropositividade para HIV/complicações , HIV-1/imunologia , Mucosa Bucal/virologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Idoso , Doenças do Ânus/virologia , Sequência de Bases/genética , Condiloma Acuminado/virologia , Epitélio/virologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Prevalência , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem
16.
PLoS One ; 15(4): e0230857, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240216

RESUMO

The nucleotide sequences of plasmids pRC12 (12,342 bp; GC 43.99%) and pRC18 (18,664 bp; GC 34.33%), harbored by the bacteriocin-producer Lactobacillus curvatus CRL 705, were determined and analyzed. Plasmids pRC12 and pRC18 share a region with high DNA identity (> 83% identity between RepA, a Type II toxin-antitoxin system and a tyrosine integrase genes) and are stably maintained in their natural host L. curvatus CRL 705. Both plasmids are low copy number and belong to the theta-type replicating group. While pRC12 is a pUCL287-like plasmid that possesses iterons and the repA and repB genes for replication, pRC18 harbors a 168 amino acid replication protein affiliated to RepB, which was named RepB'. Plasmid pRC18 also possesses a pUCL287-like repA gene but it was disrupted by an 11 kb insertion element that contains RepB', several transposases/IS elements, and the lactocin Lac705 operon. An Escherichia coli / Lactobacillus shuttle vector, named plasmid p3B1, carrying the pRC18 replicon (i.e. repB' and replication origin), a chloramphenicol resistance gene and a pBluescript backbone, was constructed and used to define the host range of RepB'. Chloramphenicol-resistant transformants were obtained after electroporation of Lactobacillus plantarum CRL 691, Lactobacillus sakei 23K and a plasmid-cured derivative of L. curvatus CRL 705, but not of L. curvatus DSM 20019 or Lactococcus lactis NZ9000. Depending on the host, transformation efficiency ranged from 102 to 107 per µg of DNA; in the new hosts, the plasmid was relatively stable as 29-53% of recombinants kept it after cell growth for 100 generations in the absence of selective pressure. Plasmid p3B1 could therefore be used for cloning and functional studies in several Lactobacillus species.


Assuntos
Lactobacillus/genética , Plasmídeos/genética , Sequência de Aminoácidos/genética , Proteínas de Bactérias/genética , Sequência de Bases/genética , Replicação do DNA/genética , DNA Bacteriano/genética , Vetores Genéticos/genética , Origem de Replicação/genética , Replicon/genética , Análise de Sequência de DNA/métodos , Transposases/genética
17.
Am J Hum Genet ; 106(4): 438-452, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32197073

RESUMO

The neuro-oncological ventral antigen 2 (NOVA2) protein is a major factor regulating neuron-specific alternative splicing (AS), previously associated with an acquired neurologic condition, the paraneoplastic opsoclonus-myoclonus ataxia (POMA). We report here six individuals with de novo frameshift variants in NOVA2 affected with a severe neurodevelopmental disorder characterized by intellectual disability (ID), motor and speech delay, autistic features, hypotonia, feeding difficulties, spasticity or ataxic gait, and abnormal brain MRI. The six variants lead to the same reading frame, adding a common proline rich C-terminal part instead of the last KH RNA binding domain. We detected 41 genes differentially spliced after NOVA2 downregulation in human neural cells. The NOVA2 variant protein shows decreased ability to bind target RNA sequences and to regulate target AS events. It also fails to complement the effect on neurite outgrowth induced by NOVA2 downregulation in vitro and to rescue alterations of retinotectal axonal pathfinding induced by loss of NOVA2 ortholog in zebrafish. Our results suggest a partial loss-of-function mechanism rather than a full heterozygous loss-of-function, although a specific contribution of the novel C-terminal extension cannot be excluded.


Assuntos
Mutação da Fase de Leitura/genética , Proteínas do Tecido Nervoso/genética , Transtornos do Neurodesenvolvimento/genética , Neurônios/fisiologia , Processamento de RNA/genética , Proteínas de Ligação a RNA/genética , Processamento Alternativo/genética , Animais , Orientação de Axônios/genética , Sequência de Bases/genética , Células Cultivadas , Pré-Escolar , Regulação para Baixo/genética , Feminino , Heterozigoto , Humanos , Deficiência Intelectual/genética , Transtornos do Desenvolvimento da Linguagem/genética , Masculino , Camundongos , Hipotonia Muscular/genética , Peixe-Zebra/genética
18.
PLoS One ; 15(3): e0227831, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32142522

RESUMO

Orthaga olivacea Warre (Lepidoptera: Pyralidae) is an important agricultural pest of camphor trees (Cinnamomum camphora). To further supplement the known genome-level features of related species, the complete mitochondrial genome of Orthaga olivacea is amplified, sequenced, annotated, analyzed, and compared with 58 other species of Lepidopteran. The complete sequence is 15,174 bp, containing 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and a putative control region. Base composition is biased toward adenine and thymine (79.02% A+T) and A+T skew are slightly negative. Twelve of the 13 PCGs use typical ATN start codons. The exception is cytochrome oxidase 1 (cox1) that utilizes a CGA initiation codon. Nine PCGs have standard termination codon (TAA); others have incomplete stop codons, a single T or TA nucleotide. All the tRNA genes have the typical clover-leaf secondary structure, except for trnS(AGN), in which dihydrouridine (DHU) arm fails to form a stable stem-loop structure. The A+T-rich region (293 bp) contains a typical Lepidopter motifs 'ATAGA' followed by a 17 bp poly-T stretch, and a microsatellite-like (AT)13 repeat. Codon usage analysis revealed that Asn, Ile, Leu2, Lys, Tyr and Phe were the most frequently used amino acids, while Cys was the least utilized. Phylogenetic analysis suggested that among sequenced lepidopteran mitochondrial genomes, Orthaga olivacea Warre was most closely related to Hypsopygia regina, and confirmed that Orthaga olivacea Warre belongs to the Pyralidae family.


Assuntos
Cinnamomum camphora/parasitologia , Genoma Mitocondrial , Mariposas/genética , Animais , Sequência de Bases/genética , Genoma de Inseto/genética , Controle de Insetos/métodos , Mariposas/patogenicidade , Controle Biológico de Vetores/métodos , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética , Análise de Sequência de DNA
19.
PLoS Comput Biol ; 16(3): e1007134, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32134915

RESUMO

Whole genome sequencing of bacteria has become daily routine in many fields. Advances in DNA sequencing technologies and continuously dropping costs have resulted in a tremendous increase in the amounts of available sequence data. However, comprehensive in-depth analysis of the resulting data remains an arduous and time-consuming task. In order to keep pace with these promising but challenging developments and to transform raw data into valuable information, standardized analyses and scalable software tools are needed. Here, we introduce ASA3P, a fully automatic, locally executable and scalable assembly, annotation and analysis pipeline for bacterial genomes. The pipeline automatically executes necessary data processing steps, i.e. quality clipping and assembly of raw sequencing reads, scaffolding of contigs and annotation of the resulting genome sequences. Furthermore, ASA3P conducts comprehensive genome characterizations and analyses, e.g. taxonomic classification, detection of antibiotic resistance genes and identification of virulence factors. All results are presented via an HTML5 user interface providing aggregated information, interactive visualizations and access to intermediate results in standard bioinformatics file formats. We distribute ASA3P in two versions: a locally executable Docker container for small-to-medium-scale projects and an OpenStack based cloud computing version able to automatically create and manage self-scaling compute clusters. Thus, automatic and standardized analysis of hundreds of bacterial genomes becomes feasible within hours. The software and further information is available at: asap.computational.bio.


Assuntos
Biologia Computacional/métodos , Análise de Sequência de DNA/métodos , Algoritmos , Bactérias/genética , Sequência de Bases/genética , Mapeamento Cromossômico/métodos , Computação em Nuvem , Genoma Bacteriano/genética , Análise de Sequência de DNA/estatística & dados numéricos , Software , Sequenciamento Completo do Genoma/métodos
20.
J Gen Virol ; 101(3): 271-283, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32134374

RESUMO

Hepatitis B virus (HBV) is a diverse, partially double-stranded DNA virus, with 9 genotypes (A-I), and a putative 10th genotype (J), characterized thus far. Given the broadening interest in HBV sequencing, there is an increasing requirement for a consistent, unified approach to HBV genotype and subgenotype classification. We set out to generate an updated resource of reference sequences using the diversity of all genomic-length HBV sequences available in public databases. We collated and aligned genomic-length HBV sequences from public databases and used maximum-likelihood phylogenetic analysis to identify genotype clusters. Within each genotype, we examined the phylogenetic support for currently defined subgenotypes, as well as identifying well-supported clades and deriving reference sequences for them. Based on the phylogenies generated, we present a comprehensive set of HBV reference sequences at the genotype and subgenotype level. All of the generated data, including the alignments, phylogenies and chosen reference sequences, are available online (https://doi.org/10.6084/m9.figshare.8851946) as a simple open-access resource.


Assuntos
Sequência de Bases/genética , Genoma Viral , Genótipo , Vírus da Hepatite B/genética , Hepatite B/virologia , DNA Viral/genética , Bases de Dados Genéticas , Humanos , Filogenia , Análise de Sequência de DNA
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