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1.
Appl Environ Microbiol ; 88(23): e0151822, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36383019

RESUMO

Xylose, the major component of lignocellulosic biomass, cannot be naturally or efficiently utilized by most microorganisms. Xylose (co)utilization is considered a cornerstone of efficient lignocellulose-based biomanufacturing. We evolved a rapidly xylose-utilizing strain, Cev2-18-5, which showed the highest reported specific growth rate (0.357 h-1) on xylose among plasmid-free Corynebacterium glutamicum strains. A genetically clear chassis strain, CGS15, was correspondingly reconstructed with an efficient glucose-xylose coutilization performance based on comparative genomic analysis and mutation reconstruction. With the introduction of a succinate-producing plasmid, the resulting strain, CGS15-SA1, can efficiently produce 97.1 g/L of succinate with an average productivity of 8.09 g/L/h by simultaneously utilizing glucose and xylose from corn stalk hydrolysate. We further revealed a novel xylose regulatory mechanism mediated by the endogenous transcription factor IpsA with global regulatory effects on C. glutamicum. A synergistic effect on carbon metabolism and energy supply, motivated by three genomic mutations (Psod(C131T)-xylAB, Ptuf(Δ21)-araE, and ipsAC331T), was found to endow C. glutamicum with the efficient xylose utilization and rapid growth phenotype. Overall, this work not only provides promising C. glutamicum chassis strains for a lignocellulosic biorefinery but also enriches the understanding of the xylose regulatory mechanism. IMPORTANCE A novel xylose regulatory mechanism mediated by the transcription factor IpsA was revealed. A synergistic effect on carbon metabolism and energy supply was found to endow C. glutamicum with the efficient xylose utilization and rapid growth phenotype. The new xylose regulatory mechanism enriches the understanding of nonnatural substrate metabolism and encourages exploration new engineering targets for rapid xylose utilization. This work also provides a paradigm to understand and engineer the metabolism of nonnatural renewable substrates for sustainable biomanufacturing.


Assuntos
Corynebacterium glutamicum , Corynebacterium glutamicum/metabolismo , Xilose/metabolismo , Glucose/metabolismo , Carbono/metabolismo , Succinatos/metabolismo , Fatores de Transcrição/genética , Engenharia Metabólica/métodos
2.
Emerg Infect Dis ; 27(11): 2940-2943, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34670650

RESUMO

In late 2020, we detected 32 highly pathogenic avian influenza A(H5N8) viruses in migratory ducks in Shanghai, China. Phylogenetic analysis of 5 representative isolates identified 2 sublineages of clade 2.3.4.4b. Each sublineage formed separate clusters with isolates from East Asia and Europe.


Assuntos
Vírus da Influenza A Subtipo H5N8 , Influenza Aviária , Animais , Animais Selvagens , Aves , China/epidemiologia , Patos , Vírus da Influenza A Subtipo H5N8/genética , Influenza Aviária/epidemiologia , Filogenia
3.
Virol J ; 18(1): 171, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34412671

RESUMO

BACKGROUND: Diallyl trisulfide (DATS) is a garlic-derived organosulfur compound. As it has been shown to have anti-viral activity, we hypothesized that it may alleviate infections caused by H9N2 avian influenza virus (AIV), which is prevalent in poultry with pandemic potential. METHODS: Human lung A549 epithelial cells were treated with three different concentrations of DATS 24 h before (pre-treatment) or one hour after (post-treatment) H9N2 AIV infection. Culture supernatants were collected 24 h and 48 h post-infection and analyzed for viral titers and levels of inflammatory and anti-viral immune responses. For in vivo experiments, BABL/c mice were administered daily by intraperitoneal injection with DATS (30 mg/kg) for 2 weeks starting 1 day after H9N2 AIV infection. Clinical signs, lung pathology, and inflammatory and anti-viral immune responses were assessed 2, 4, and 6 days after infection. RESULTS: Both pre-treatment and post-treatment of A549 cells with DATS resulted in reduced viral loads, increased expression of anti-viral genes (RIG-I, IRF-3, and interferon-ß), and decreased expression of inflammatory cytokines (TNF-α and IL-6). These effects were also observed in H9N2 AIV-infected mice treated with DATS. Such treatment also reduced lung edema and inflammation in mice. CONCLUSIONS: Results suggest that DATS has anti-viral activity against H9N2 AIV and may be used as an alternative treatment for influenza virus infection.


Assuntos
Compostos Alílicos/farmacologia , Antivirais/farmacologia , Vírus da Influenza A Subtipo H9N2 , Infecções por Orthomyxoviridae/tratamento farmacológico , Sulfetos/farmacologia , Células A549 , Animais , Galinhas , Humanos , Vírus da Influenza A Subtipo H9N2/efeitos dos fármacos , Influenza Aviária/tratamento farmacológico , Camundongos
4.
Virol J ; 17(1): 62, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32349760

RESUMO

BACKGROUND: H6 subtype influenza viruses were prevalent in domestic poultry and wild birds, which also could pose potential threat to humans. However, little is known about the prevalence of H6 subtype viruses in wild birds in eastern China, a crucial stopover or wintering site for migratory wild birds along the East Asian-Australasian Flyway. METHODS: During the routine surveillance in 2016-2017, H6 subtype AIVs positive samples were identified, and the representative strains were selected for further sequence and phylogenetic analysis and the pathogenicity in mice were evaluated. RESULTS: Among the 30 H6 positive samples, there were at least four subtypes H6N1, H6N2, H6N5 and H6N8 co-circulated in Shanghai, China. Genetic analysis showed the 8 representative isolates shared homology with different AIV sub-lineages isolated from domestic ducks or wild birds in different countries along the East Asian-Australasian flyways, and were classified into 7 new genotypes. The pathogenicity to mice showed that these H6 viruses could replicate efficiently in the lungs without prior adaptation, but could not cause mice death. CONCLUSIONS: Eight novel strains belonged to H6N1, H6N2, H6N5 and H6N8 subtypes were isolated. Phylogenetic analyses revealed multiple origins of internal genes indicative of robust reassortment events and frequent wild birds-poultry interaction encouraging the evolution and emergence of new genotypes. The pathogenicity to mammals should be closely monitored to prevent the emergence of novel pandemic viruses.


Assuntos
Animais Selvagens/virologia , Aves/virologia , Vírus da Influenza A/genética , Influenza Aviária/virologia , Filogenia , Vírus Reordenados/genética , Animais , China/epidemiologia , Genótipo , Vírus da Influenza A/classificação , Influenza Aviária/epidemiologia , RNA Viral/genética , Vírus Reordenados/classificação
5.
Virol J ; 14(1): 10, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28114957

RESUMO

BACKGROUND: H9N2 influenza viruses circulate globally and are considered to have pandemic potential. The hyper-inflammatory response elicited by these viruses is thought to contribute to disease severity. Calcitriol plays an important role in modulating the immune response to viral infections. However, its unknown whether calcitriol can attenuate the inflammatory response elicited by H9N2 influenza virus infection. METHODS: Human lung A549 epithelial cells were treated with calcitriol (100 nM) and then infected with an H9N2 influenza virus, or infected and then treated with calcitriol (30 nM). Culture supernatants were collected every 24 h post infection and the viral growth kinetics and inflammatory response were evaluated. Calcitriol (5 mg/kg) was administered daily by intraperitoneal injection to BABL/c mice for 15 days following H9N2 influenza virus infection. Mice were monitored for clinical signs of disease, lung pathology and inflammatory responses. RESULTS: Calcitriol treatment prior to and post infection with H9N2 influenza significantly decreased expression of the influenza M gene, IL-6, and IFN-ß in A549 cells, but did not affect virus replication. In vivo, we found that calcitriol treatment significantly downregulated pulmonary inflammation in mice 2 days post-infection, but increased the inflammatory response 4 to 6 days post-infection. In contrast, the antiviral cytokine IFN-ß was significantly higher in calcitriol-treated mice than in the untreated infected mice at 2 days post-infection, but lower than in untreated infected mice on days 4 and 8 post-infection. The elevated levels of pro-inflammatory cytokines and the decreased levels of antiviral cytokine are consistent with the period of maximum body weight loss and the lung damage in calcitriol-treated mice. CONCLUSIONS: These results suggest that calcitriol treatment might have a negative impact on the innate immune response elicited by H9N2 infection in mice, especially at the later stage of influenza virus infection. This study will provide some novel insights into the use of calcitriol to modulate the inflammatory response elicited by influenza virus infection in humans.


Assuntos
Calcitriol/administração & dosagem , Calcitriol/farmacologia , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/farmacologia , Inflamação/patologia , Vírus da Influenza A Subtipo H9N2/patogenicidade , Infecções por Orthomyxoviridae/tratamento farmacológico , Animais , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Feminino , Humanos , Imunidade Inata/efeitos dos fármacos , Vírus da Influenza A Subtipo H9N2/crescimento & desenvolvimento , Injeções Intraperitoneais , Pulmão/patologia , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Resultado do Tratamento
6.
Mol Biol Evol ; 31(11): 2829-35, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25135943

RESUMO

The role of gene duplication in generating new genes and novel functions is well recognized and is exemplified by the digestion-related protein lysozyme. In ruminants, duplicated chicken-type lysozymes facilitate the degradation of symbiotic bacteria in the foregut. Chicken-type lysozyme has also been reported to show chitinase-like activity, yet no study has examined the molecular evolution of lysozymes in species that specialize on eating insects. Insectivorous bats number over 900 species, and lysozyme expression in the mouths of some of these species is associated with the ingestion of insect cuticle, suggesting a chitinase role. Here, we show that chicken-type lysozyme has undergone multiple duplication events in a major family of insect-eating bats (Vespertilionidae) and that new duplicates have undergone molecular adaptation. Examination of duplicates from two insectivorous bats-Pipistrellus abramus and Scotophilus kuhlii-indicated that the new copy was highly expressed in the tongue, whereas the other one was less tissue-specific. Functional assays applied to pipistrelle lysozymes confirmed that, of the two copies, the tongue duplicate was more efficient at breaking down glycol chitin, a chitin derivative. These results suggest that the evolution of lysozymes in vespertilionid bats has likely been driven in part by natural selection for insectivory.


Assuntos
Adaptação Fisiológica , Quirópteros/genética , Quitinases/metabolismo , Evolução Molecular , Muramidase/metabolismo , Filogenia , Animais , Galinhas/metabolismo , Quirópteros/classificação , Quirópteros/metabolismo , Quitina/análogos & derivados , Quitina/metabolismo , Quitinases/química , Quitinases/genética , Ensaios Enzimáticos , Escherichia coli/genética , Escherichia coli/metabolismo , Duplicação Gênica , Expressão Gênica , Variação Genética , Insetos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Muramidase/química , Muramidase/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Seleção Genética , Língua/enzimologia
7.
Antimicrob Agents Chemother ; 59(5): 2654-65, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25691649

RESUMO

There is currently no approved antiviral therapy for the prophylaxis or treatment of enterovirus infections, which remain a substantial threat to public health. To discover inhibitors that can be immediately repurposed for treatment of enterovirus infections, we developed a high-throughput screening assay that measures the cytopathic effect induced by enterovirus 71 (EV71) to screen an FDA-approved drug library. Itraconazole (ITZ), a triazole antifungal agent, was identified as an effective inhibitor of EV71 replication in the low-micromolar range (50% effective concentrations [EC50s], 1.15 µM). Besides EV71, the compound also inhibited other enteroviruses, including coxsackievirus A16, coxsackievirus B3, poliovirus 1, and enterovirus 68. Study of the mechanism of action by time-of-addition assay and transient-replicon assay revealed that ITZ targeted a step involved in RNA replication or polyprotein processing. We found that the mutations (G5213U and U5286C) conferring the resistance to the compound were in nonstructural protein 3A, and we confirmed the target amino acid substitutions (3A V51L and 3A V75A) using a reverse genetic approach. Interestingly, posaconazole, a new oral azole with a molecular structure similar to that of ITZ, also exhibited anti-EV71 activity. Moreover, ITZ-resistant viruses do not exhibit cross-resistance to posaconazole or the enviroxime-like compound GW5074, which also targets the 3A region, indicating that they may target a specific site(s) in viral genome. Although the protective activity of ITZ or posaconazole (alone or in combination with other antivirals) remains to be assessed in animal models, our findings may represent an opportunity to develop therapeutic interventions for enterovirus infection.


Assuntos
Antivirais/farmacologia , Itraconazol/farmacologia , Proteínas não Estruturais Virais/metabolismo , Linhagem Celular Tumoral , Farmacorresistência Viral/genética , Enterovirus/efeitos dos fármacos , Enterovirus/patogenicidade , Humanos , Transfecção , Proteínas não Estruturais Virais/genética , Replicação Viral/efeitos dos fármacos
8.
Virol J ; 12: 83, 2015 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-26036928

RESUMO

BACKGROUND: In 2012 a large outbreak of hand, foot, and mouth disease (HFMD) widely spread over China, causing more than 2 million cases and 567 deaths. Our purpose was to characterize the major pathogens responsible for the 2012 HFMD outbreak and analyze the genetic characterization of the enterovirus 71 (EV71) strains in Shanghai; also, to analyze the dynamic patterns of neutralizing antibody (NAb) against EV71 and evaluate the diagnostic value of several methods for clinical detection of EV71. METHODS: Clinical samples including stool, serum and CSF were collected from 396 enrolled HFMD inpatients during the peak seasons in 2012. We analyzed the molecular epidemiology, clinical feature, and diagnostic tests of EV71 infection. RESULTS: EV71 was responsible for 60.35 % of HFMD inpatients and 88.46 % of severe cases. The circulating EV71 strains belonged to subgenogroup C4a. The nucleotide sequences of VP1 between severe cases and uncomplicated cases shared 99.2 ~ 100 % of homology. Among 218 cases with EV71 infection, 211 (96.79 %) serum samples showed NAb positive against EV71 and NAb titer reached higher level 3 days after disease onset. Of 92 cases with EV71-associated meningitis or encephalitis, 5 (5.43 %) of 92 had EV71 RNA detected in CSF samples. The blood anti-EV71 IgM assay showed a sensitivity of 93.30 % and a specificity of 50 %. CONCLUSIONS: EV71 C4a remained the predominant subgenotype circulating in Shanghai. The severity of the EV71 infection is not associated with the virulence determinants in VP1. RT-PCR together with IgM detection can enhance the early diagnosis of severe EV71-associated HFMD.


Assuntos
Surtos de Doenças , Enterovirus Humano A/isolamento & purificação , Doença de Mão, Pé e Boca/diagnóstico , Doença de Mão, Pé e Boca/epidemiologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Líquido Cefalorraquidiano/virologia , Criança , Pré-Escolar , China/epidemiologia , Análise por Conglomerados , Diagnóstico Precoce , Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Fezes/virologia , Feminino , Doença de Mão, Pé e Boca/patologia , Humanos , Imunoglobulina M/sangue , Lactente , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência , Soro/virologia , Proteínas Estruturais Virais/genética
9.
Arch Virol ; 159(6): 1359-64, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24357081

RESUMO

H5N1 viruses cause severe and often fatal disease in humans. DNA vaccines have been shown to provide some protection in many animal models against H5N1 influenza virus infection, but this protection is not complete. To enhance the immunogenicity of an H5N1 DNA vaccine, we constructed the eukaryotic expression systems pcD-CD40 and pcD-HA. The expression of pcD-HA or pcD-CD40 in transfected BHK cells was confirmed by reverse transcription polymerase chain reaction (RT-PCR). The constructs were then used to immunize BALB/c mice intramuscularly three times at two-week intervals. The titers of serum HA-specific antibodies were determined by ELISA, and the expression levels of the cytokines IL-2, IL-4, IL-6 and TNF-α were determined by real-time PCR. The results showed that CD40 as a molecular adjuvant significantly enhanced the production of serum anti-HA antibodies and increased the levels of the Th2 cytokines IL-4 and IL-6, suggesting that co-immunization with CD40 upregulated the humoral immune responses to the DNA vaccine in BALB/c mice. This study will provide important information for the selection of adjuvants for DNA vaccines against HPAI H5N1 viruses or other subtypes of human influenza viruses.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antígenos CD40/administração & dosagem , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Vacinas de DNA/imunologia , Adjuvantes Imunológicos/genética , Animais , Anticorpos Antivirais/sangue , Antígenos CD40/genética , Citocinas/biossíntese , Ensaio de Imunoadsorção Enzimática , Perfilação da Expressão Gênica , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Virus da Influenza A Subtipo H5N1/genética , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Injeções Intramusculares , Leucócitos Mononucleares/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real , Vacinação/métodos , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética
10.
Gen Comp Endocrinol ; 204: 80-7, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24815886

RESUMO

Previous studies have shown that the hormone Leptin has an important role in mammalian heterothermy by regulating metabolism and food intake via lipolysis, as well as adaptive evolution of Leptin in heterothermic bats driven by selected pressure. However, the mechanism of Leptin in heterothermic regulation in mammals is unknown. By combining previous results, we speculated that the Leptin signaling pathway mediated by OB-RL (Leptin receptor long form) in the hypothalamus is important. OB-RL is one of the products of db gene and mainly distributed in the hypothalamus. In this study, we used OB-RL as a molecular marker, combining with the RNA interference technology and physiological/molecular analyses with Hipposideros armiger (a hibernating bat species) as an animal model, to explore the mechanism of Leptin in heterothermic regulation. Our data showed that all of four anti-OB-RL shRNA lentivirus significantly inhibited OB-RL expression (>90%), and the interference efficiency of PSC1742 lentivirus reached the highest value. In situ hybridization proved that PSC1742 lentivirus significantly decreased the OB-RL expression in the hypothalamus, especially in the ventromedial hypothalamic nucleus (VHM, 86.6%). Physiological analysis demonstrated that the thermoregulatory ability of bats (e.g., reducing core body temperature and heart rate) was significantly depressed after OB-RL silencing in the hypothalamus, and animals could not enter torpor state. Our study for the first time proved that the knock-down of OB-RL expression in hypothalamus inhibits heterothermic regulation of bats, and also provided the clues for further analyzing the mechanism of Leptin in the heterothermic regulation of mammals.


Assuntos
Regulação da Temperatura Corporal , Quirópteros/fisiologia , Inativação Gênica , RNA Interferente Pequeno/genética , Receptores para Leptina/genética , Animais , Frequência Cardíaca , Hipotálamo/metabolismo , Hibridização In Situ , Leptina/metabolismo , Masculino
11.
Emerg Infect Dis ; 19(6): 989-91, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23739658

RESUMO

To clarify the evolutionary relationships among betavoronaviruses that infect bats, we analyzed samples collected during 2010-2011 from 14 insectivorous bat species in China. We identified complete genomes of 2 novel betacoronaviruses in Rhinolophus pusillus and Chaerephon plicata bats, which showed close genetic relationships with severe acute respiratory syndrome coronaviruses.


Assuntos
Quirópteros/virologia , Coronavirus/classificação , Animais , Coronavirus/genética , Coronavirus/isolamento & purificação , Genes Virais , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Dados de Sequência Molecular , Filogenia
12.
J Virol ; 86(20): 10999-1012, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22855479

RESUMO

Bats are natural hosts for a large variety of zoonotic viruses. This study aimed to describe the range of bat viromes, including viruses from mammals, insects, fungi, plants, and phages, in 11 insectivorous bat species (216 bats in total) common in six provinces of China. To analyze viromes, we used sequence-independent PCR amplification and next-generation sequencing technology (Solexa Genome Analyzer II; Illumina). The viromes were identified by sequence similarity comparisons to known viruses. The mammalian viruses included those of the Adenoviridae, Herpesviridae, Papillomaviridae, Retroviridae, Circoviridae, Rhabdoviridae, Astroviridae, Flaviridae, Coronaviridae, Picornaviridae, and Parvovirinae; insect viruses included those of the Baculoviridae, Iflaviridae, Dicistroviridae, Tetraviridae, and Densovirinae; fungal viruses included those of the Chrysoviridae, Hypoviridae, Partitiviridae, and Totiviridae; and phages included those of the Caudovirales, Inoviridae, and Microviridae and unclassified phages. In addition to the viruses and phages associated with the insects, plants, and bacterial flora related to the diet and habitation of bats, we identified the complete or partial genome sequences of 13 novel mammalian viruses. These included herpesviruses, papillomaviruses, a circovirus, a bocavirus, picornaviruses, a pestivirus, and a foamy virus. Pairwise alignments and phylogenetic analyses indicated that these novel viruses showed little genetic similarity with previously reported viruses. This study also revealed a high prevalence and diversity of bat astroviruses and coronaviruses in some provinces. These findings have expanded our understanding of the viromes of bats in China and hinted at the presence of a large variety of unknown mammalian viruses in many common bat species of mainland China.


Assuntos
Quirópteros/virologia , Genoma Viral , Vírus/classificação , Vírus/genética , Animais , Bacteriófagos/classificação , China , Fungos/virologia , Variação Genética , Vírus de Insetos/classificação , Vírus de Insetos/genética , Vírus de Insetos/isolamento & purificação , Insetos/virologia , Mamíferos/virologia , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Filogenia , Vírus de Plantas/classificação , Vírus de Plantas/genética , Vírus de Plantas/isolamento & purificação , Plantas/virologia , Vírus/isolamento & purificação
13.
Mol Ecol ; 22(4): 1035-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23205821

RESUMO

Phylogenetic conflicts between genetic markers can help to disentangle complex histories of phylogeography and introgression among taxa. We previously proposed that the Chinese mainland subspecies of the intermediate horseshoe bat Rhinolophus affinis himalayanus colonized Hainan Island to form the subspecies R. a. hainanus. Subsequent recolonization of the mainland formed a third taxon, R. a macrurus, and a secondary contact zone with the ancestral himalayanus. To test for historical and recurrent genetic exchange between these mainland subspecies, we sampled populations of each from two parapatric zones and undertook analyses using one mtDNA marker, three nuclear genes and 14 microsatellites. Nuclear DNA, echolocation call frequencies and morphological data all recovered two taxa; however, a mtDNA phylogeny revealed two himalayanus clades, of which one clustered with macrurus, as well as some shared or related mtDNA haplotypes in eastern populations. Isolation-with-migration (IM) models suggested some mtDNA gene flow from macrurus to himalayanus. However, strong population structure in himalayanus raises the possibility that macrurus captured mtDNA from a coastal population of himalayanus that has since become rare or extinct. To reconcile these two sets of results, we suggest that the IM estimates might reflect historical mtDNA gene flow among populations of himalayanus, before mtDNA was subsequently captured by macrurus. Finally, microsatellite-based ABC analyses supported the island origin of macrurus; however, mtDNA-based ABC analyses suggest this taxon might have evolved on the mainland. Our findings highlight the importance of understanding population history and structure for interpreting hybridization and introgression events.


Assuntos
Quirópteros/genética , Evolução Molecular , Fluxo Gênico , Genética Populacional , Hibridização Genética , Alelos , Animais , Teorema de Bayes , Núcleo Celular/genética , China , Quirópteros/classificação , DNA Mitocondrial/genética , Ecolocação , Variação Genética , Haplótipos , Ilhas , Repetições de Microssatélites , Modelos Genéticos , Filogenia , Análise de Sequência de DNA
14.
Biochem Genet ; 51(1-2): 7-19, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23053874

RESUMO

Old World fruit bats (Pteropodidae) and New World fruit bats (Phyllostomidae) ingest significant quantities of ethanol while foraging. Mitochondrial aldehyde dehydrogenase (ALDH2, encoded by the Aldh2 gene) plays an important role in ethanol metabolism. To test whether the Aldh2 gene has undergone adaptive evolution in frugivorous and nectarivorous bats in relation to ethanol elimination, we sequenced part of the coding region of the gene (1,143 bp, ~73 % coverage) in 14 bat species, including three Old World fruit bats and two New World fruit bats. Our results showed that the Aldh2 coding sequences are highly conserved across all bat species we examined, and no evidence of positive selection was detected in the ancestral branches leading to Old World fruit bats and New World fruit bats. Further research is needed to determine whether other genes involved in ethanol metabolism have been the targets of positive selection in frugivorous and nectarivorous bats.


Assuntos
Aldeído Desidrogenase/genética , Quirópteros/genética , Clonagem Molecular , Evolução Molecular , Aldeído Desidrogenase/química , Sequência de Aminoácidos , Animais , Humanos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
15.
Poult Sci ; 102(10): 102948, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37604021

RESUMO

The H4 subtype of avian influenza viruses has been widely distributed among wild birds. During the surveillance of the avian influenza virus in Shanghai from 2019 to 2021, a total of 4,451 samples were collected from wild birds, among which 46 H4 subtypes of avian influenza viruses were identified, accounting for 7.40% of the total positive samples. The H4 subtype viruses have a wide range of hosts, including the spot-billed duck, common teal, and other wild birds in Anseriformes. Among all H4 subtypes, the most abundant are the H4N2 viruses. To clarify the genetic characteristics of H4N2 viruses, the whole genome sequences of 20 H4N2 viruses were analyzed. Phylogenetical analysis showed that all 8 genes of these viruses belonged to the Eurasian lineage and closely clustered with low pathogenic avian influenza viruses from countries along the East Asia-Australia migratory route. However, the PB1 gene of 1 H4N2 virus (NH21920) might provide its internal gene for highly pathogenic avian influenza H5N8 viruses in Korea and Japan. At least 10 genotypes were identified in these viruses, indicating that they underwent multiple complex recombination events. Our study has provided a better epidemiological understanding of the H4N2 viruses in wild birds. Considering the mutational potential, comprehensive surveillance of the H4N2 virus in both poultry and wild birds is imperative.


Assuntos
Vírus da Influenza A , Influenza Aviária , Animais , Influenza Aviária/epidemiologia , Galinhas , China/epidemiologia , Animais Selvagens , Vírus da Influenza A/genética , Patos , Filogenia
16.
Viruses ; 15(5)2023 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-37243207

RESUMO

Avian coronaviruses (ACoV) have been shown to be highly prevalent in wild bird populations. More work on avian coronavirus detection and diversity estimation is needed for the breeding territories of migrating birds, where the high diversity and high prevalence of Orthomyxoviridae and Paramyxoviridae have already been shown in wild birds. In order to detect ACoV RNA, we conducted PCR diagnostics of cloacal swab samples from birds, which we monitored during avian influenza A virus surveillance activities. Samples from two distant Asian regions of Russia (Sakhalin region and Novosibirsk region) were tested. Amplified fragments of the RNA-dependent RNA-polymerase (RdRp) of positive samples were partially sequenced to determine the species of Coronaviridae represented. The study revealed a high presence of ACoV among wild birds in Russia. Moreover, there was a high presence of birds co-infected with avian coronavirus, avian influenza virus, and avian paramyxovirus. We found one case of triple co-infection in a Northern Pintail (Anas acuta). Phylogenetic analysis revealed the circulation of a Gammacoronavirus species. A Deltacoronavirus species was not detected, which supports the data regarding the low prevalence of deltacoronaviruses among surveyed bird species.


Assuntos
Avulavirus , Gammacoronavirus , Vírus da Influenza A , Influenza Aviária , Animais , Patos , Gammacoronavirus/genética , Influenza Aviária/epidemiologia , Avulavirus/genética , Sibéria/epidemiologia , Filogenia , Aves , Animais Selvagens , Vírus da Influenza A/genética , RNA
17.
Biochem Genet ; 50(3-4): 235-48, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21952875

RESUMO

A newly discovered melanopsin gene (Opn4) encodes a member of the opsins, melanopsin. Two melanopsin genes, mammalian-like Opn4m and Xenopus-like Opn4x, have been described in nonmammalian vertebrates, but the underlying evolutionary mechanisms behind the duplication of melanopsin genes remain unclear. We conducted a comprehensive evolutionary analysis within a phylogenetic framework. In our phylogenetic tree, the duplication of Opn4m and Opn4x probably occurred prior to the emergence of vertebrates, and subsequently Opn4x disappeared in the lineages leading to mammalian species. Evolutionary analyses show strong purifying selection during melanopsin evolution. We also provide evidence that Opn4x underwent positive selection after the early gene duplication events. It has been indicated that functional divergence and altered functional constraints occurred between Opn4m and Opn4x duplicates with the identification of positively selected amino acids. Our findings highlight the evolutionary malleability in vertebrate melanopsin genes and provide a genetic basis for comparative studies of functional properties of these two melanopsins.


Assuntos
Duplicação Gênica , Variação Genética , Opsinas de Bastonetes/genética , Seleção Genética , Sequência de Aminoácidos , Animais , Evolução Molecular , Humanos , Funções Verossimilhança , Cadeias de Markov , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Conformação Proteica , Alinhamento de Sequência , Análise de Sequência de DNA , Vertebrados/genética
18.
Biochem Genet ; 50(3-4): 213-26, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21948254

RESUMO

GJB6 plays a crucial role in hearing. In mammals, bats use ultrasonic echolocation for orientation and locating prey. To investigate the evolution of GJB6 in mammals, we cloned the full-length coding region of GJB6 from 16 species of bats and 4 other mammal species and compared them with orthologous sequences in 11 other mammals. The results show purifying selection on GJB6 in mammals, as well as in the bat lineage, which indicates an important role for GJB6 in mammal hearing. We also found one unique amino acid substitution shared by 16 species of bats and 10 shared by two species of artiodactyls. This positioned the artiodactyls at an abnormal location in the gene tree. In addition, the cytoplasmic loop and carboxy terminus were more variable than other domains in all the mammals. These results demonstrate that GJB6 is basically conserved in mammals but has undergone relatively rapid evolution in particular lineages and domains.


Assuntos
Conexinas/genética , Evolução Molecular , Mamíferos/genética , Motivos de Aminoácidos/genética , Animais , Clonagem Molecular , Conexinas/química , Modelos Genéticos , Filogenia , Estrutura Terciária de Proteína/genética , Alinhamento de Sequência , Análise de Sequência de DNA
19.
Sci Total Environ ; 834: 155355, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35460779

RESUMO

Plastics have been found to be colonized with pathogens and may become vectors for transmission of diseases. In this study, we evaluated the persistence of H9N2 avian influenza virus (AIV) on the surfaces of various plastics (PP, PE, PS, PET, PVC, PMMA) under different environmental conditions using glass and stainless steel for comparison. Our results showed that the RNA abundance of AIV on plastics was decreased over time but still detectable 14 days after AIV had been dropped on plastic surfaces. Low temperature (4 °C) was more favorable for AIV RNA preservation and infectivity maintenance. The abundance of AIV RNA was significantly greater on polyethylene terephthalate (PET) than that on glass and stainless steel at higher temperature (i.e., 25 °C and 37 °C) and lower humidity (<20% and 40-60%) (p < 0.05). Infectivity assay showed that AIV infectivity was only maintained at 4 °C after 24 h of incubation. Taken together, the persistence of AIV was more affected by environmental factors than material types. Plastics were able to preserve viral RNA more effectively in relatively high-temperature or low-humidity environments. Our study indicates that environmental factors should be taken into consideration when we evaluate the capacity of plastics to spread viruses.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Animais , Galinhas/genética , Vírus da Influenza A Subtipo H9N2/genética , Plásticos , RNA Viral , Aço Inoxidável
20.
Front Psychol ; 13: 830698, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360628

RESUMO

Objective: To investigate the influence of quality of life (QOL) on unhealthy emotions as well as relevant factors among patients with endometriosis for supporting relevant clinical care. Methods: A convenience sampling method was used to administer questionnaires to 139 patients with endometriosis, using the Hamilton Anxiety Inventory (HAMA), the Depression Anxiety Scale (SDS), and the SF-12 Health Survey Short Form, and the results were analyzed. The SPSS20.0 software was used for statistical analysis on relevant data. If P < 0.05, there was statistical significance. Results: Twelve-Item Short Form (SF-12) for health survey covered two comprehensive indexes, i.e., physical component summary (PCS) and mental component summary (MCS) scores. MCS score was the main factor influencing anxiety and depression in patients with endometriosis; the higher the MCS score, the lower the anxiety and depression degrees in patients with endometriosis (OR = 0.912, 95% CI: 0.877-0.949; OR = 0.899, 95% CI: 0.866-0.933). PCS score was a factor influencing anxiety degree; the higher the PCS score, the lower the anxiety degree (OR = 0.936, 95% CI: 0.891-0.983). Conclusion: The QOL of patients with endometriosis is negatively correlated with anxiety and depression. Therefore, improvement in QOL may help relevant patients to relieve their unhealthy emotions.

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