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Viruses Jun 2023Astroviruses (AstVs) have been detected in a wide range of animal species, including mammals and birds. Recently, a novel AstV associated with neurological symptoms has...
Astroviruses (AstVs) have been detected in a wide range of animal species, including mammals and birds. Recently, a novel AstV associated with neurological symptoms has been detected in the brains of some mammals. Raccoon dog AstV has been reported recently in China. However, there have been no reports in South Korea. Therefore, the present study aimed to detect and genetically characterize AstVs in the intestine and brain tissues of 133 wild raccoon dogs collected in Korea between 2017 and 2019. Of the seven raccoon dogs, AstVs were detected in six intestinal tissues and four brain tissues. Analysis of the capsid protein amino acid sequences of raccoon dog AstVs detected in Korea revealed a high similarity to canine AstVs, suggesting possible interspecies transmission between raccoon dogs and dogs. Phylogenetic and capsid protein amino acid sequence analysis of raccoon dog AstVs detected in the brain the 17-148B strain belonging to the HMO clade and exhibiting conserved sequences found in neurotropic AstVs (NT-AstVs), indicating their potential as NT-AstVs. However, the pathogenicity and transmission routes of the raccoon dog AstV detected in Korea have not yet been elucidated, so further research and continued surveillance for AstV in wild raccoon dogs are needed.
Topics: Animals; Dogs; Astroviridae Infections; Phylogeny; Raccoon Dogs; Capsid Proteins; Astroviridae
PubMed: 37515175
DOI: 10.3390/v15071488 -
Journal of Virology Aug 2023The human astrovirus (HAstV) is a non-enveloped, single-stranded RNA virus that is a common cause of gastroenteritis. Most non-enveloped viruses use membrane disruption...
The human astrovirus (HAstV) is a non-enveloped, single-stranded RNA virus that is a common cause of gastroenteritis. Most non-enveloped viruses use membrane disruption to deliver the viral genome into a host cell after virus uptake. The virus-host factors that allow for HAstV cell entry are currently unknown but thought to be associated with the host-protease-mediated viral maturation. Using liposome disruption analysis, we identified a trypsin-dependent lipid disruption activity in the capsid protein of HAstV serotype 8. This function was further localized to the P1 domain of the viral capsid core, which was both necessary and sufficient for membrane disruption. Site-directed mutagenesis identified a cluster of four trypsin cleavage sites necessary to retain the lipid disruption activity, which is likely attributed to a short stretch of sequence ending at arginine 313 based on mass spectrometry of liposome-associated peptides. The membrane disruption activity was conserved across several other HAstVs, including the emerging VA2 strain, and effective against a wide range of lipid identities. This work provides key functional insight into the protease maturation process essential to HAstV infectivity and presents a method to investigate membrane penetration by non-enveloped viruses . IMPORTANCE Human astroviruses (HAstVs) are an understudied family of viruses that cause mild gastroenteritis but have recent cases associated with a more severe neural pathogenesis. Many important elements of the HAstV life cycle are not well understood, and further elucidating them can help understand the various forms of HAstV pathogenesis. In this study, we utilized an liposome-based assay to describe and characterize a previously unreported lipid disruption activity. This activity is dependent on the protease cleavage of key sites in HAstV capsid core and can be controlled by site-directed mutagenesis. Our group observed this activity in multiple strains of HAstV and in multiple lipid conditions, indicating this may be a conserved activity across the AstV family. The discovery of this function provides insight into HAstV cellular entry, pathogenesis, and a possible target for future therapeutics.
Topics: Humans; Capsid Proteins; Mamastrovirus; Trypsin; Liposomes; Peptides; Gastroenteritis; Lipids; Astroviridae Infections; Phylogeny
PubMed: 37504573
DOI: 10.1128/jvi.00802-23 -
The Veterinary Record Jul 2023
Topics: Animals; Geese; Avastrovirus; Poultry Diseases; Astroviridae Infections; Phylogeny; China
PubMed: 37477330
DOI: 10.1002/vetr.3297 -
PLoS Biology Jul 2023During the last decade, the detection of neurotropic astroviruses has increased dramatically. The MLB genogroup of astroviruses represents a genetically distinct group...
During the last decade, the detection of neurotropic astroviruses has increased dramatically. The MLB genogroup of astroviruses represents a genetically distinct group of zoonotic astroviruses associated with gastroenteritis and severe neurological complications in young children, the immunocompromised, and the elderly. Using different virus evolution approaches, we identified dispensable regions in the 3' end of the capsid-coding region responsible for attenuation of MLB astroviruses in susceptible cell lines. To create recombinant viruses with identified deletions, MLB reverse genetics (RG) and replicon systems were developed. Recombinant truncated MLB viruses resulted in imbalanced RNA synthesis and strong attenuation in iPSC-derived neuronal cultures confirming the location of neurotropism determinants. This approach can be used for the development of vaccine candidates using attenuated astroviruses that infect humans, livestock animals, and poultry.
Topics: Child; Animals; Humans; Child, Preschool; Aged; Mamastrovirus; Astroviridae Infections; Gastroenteritis; Capsid Proteins; Capsid; Phylogeny
PubMed: 37459343
DOI: 10.1371/journal.pbio.3001815 -
Gut Microbes 2023Diarrhea is a leading cause of morbidity and mortality in children worldwide and represents a major dysbiosis event. Rotavirus has been recognized as a global leading...
Diarrhea is a leading cause of morbidity and mortality in children worldwide and represents a major dysbiosis event. Rotavirus has been recognized as a global leading pathogen of diarrhea. This study is aimed at investigating differences in the gut virome between diarrheal children and healthy controls. In 2018, 76 diarrheal fecal samples and 27 healthy fecal samples in Shanghai and 40 diarrheal fecal samples and 19 healthy fecal samples in Taizhou were collected to investigate the composition of the gut virome. Viral metagenomic analyses revealed that the alpha diversity of the diarrheal virome was not significantly different from that of the healthy virome, and the beta diversity had a significant difference between diarrheal and healthy children. The diarrheal virome was mainly dominated by the families , , , and . Meanwhile, the healthy virome also contains phages, including and . The high prevalence of diverse enteric viruses in all samples and the little abundance of and in diarrheal groups were identified. The study introduced a general overview of the gut virome in diarrheal children, revealed the compositional differences in the gut viral community compared to healthy controls, and provided a reference for efficient treatments and prevention of virus-infectious diarrhea in children.
Topics: Humans; Child; Rotavirus; Metagenomics; Gastrointestinal Microbiome; China; Diarrhea; Rotavirus Infections; Feces
PubMed: 37448101
DOI: 10.1080/19490976.2023.2234653 -
Journal of Medical Virology Jul 2023Human astrovirus (HAstV) is a single-stranded, positive-sense RNA virus and is the leading cause of viral gastroenteritis. However, despite its prevalence, astroviruses...
Human astrovirus (HAstV) is a single-stranded, positive-sense RNA virus and is the leading cause of viral gastroenteritis. However, despite its prevalence, astroviruses still remain one of the least studied enteroviruses. In this study, we sequenced 11 classical astrovirus strains from clinical samples collected in Shenzhen, China from 2016 to 2019, analyzed their genetic characteristics, and deposited them into GenBank. We conducted phylogenetic analysis using IQ-TREE software, with references to astrovirus sequences worldwide. The phylogeographic analysis was performed using the Bayesian Evolutionary Analysis Sampling Trees program, through Bayesian Markov Chain Monte Carlo sampling. We also conducted recombination analysis with the Recombination Detection Program. The newly sequenced strains were categorized as HAstV genotype 1, which is the predominant genotype in Shenzhen. Phylogeographic reconstruction indicated that HAstV-1 may have migrated from the United States to China, followed by frequent transmission between China and Japan. The recombination analysis revealed recombination events within and across genotypes, and identified a recombination-prone region that produced relatively uniform recombination breakpoints and fragment lengths. The genetic analysis of HAstV strains in Shenzhen addresses the current lack of astrovirus data in the region of Shenzhen and provides key insights to the evolution and transmission of astroviruses worldwide. These findings highlight the importance of improving surveillance of astroviruses.
Topics: Humans; Phylogeny; Bayes Theorem; Astroviridae Infections; RNA, Viral; Feces; Astroviridae; Mamastrovirus; China; Genotype
PubMed: 37394758
DOI: 10.1002/jmv.28902 -
Heliyon Jun 2023Viral diseases caused by new outbreaks of viral infections pose a serious threat to human health. Wild brown rats (), considered one of the world's largest and most...
Viral diseases caused by new outbreaks of viral infections pose a serious threat to human health. Wild brown rats (), considered one of the world's largest and most widely distributed rodents, are host to various zoonotic pathogens. To further understand the composition of the virus community in wild brown rats and explore new types of potentially pathogenic viruses, viral metagenomics was conducted to investigate blood, feces, and various tissues of wild brown rats captured from Zhenjiang, China. Results indicated that the composition of the virus community in different samples showed significant differences. In blood and tissue samples, members of the and form the main body of the virus community. , and made up a large proportion of fecal samples. Several novel genome sequences from members of different families, including , , and CRESS DNA viruses, were detected in both blood and other samples, suggesting that they have the potential to spread across organs to cause viremia. These viruses included not only strains closely related to human viruses, but also a potential recombinant virus. Multiple dual-segment picornaviruses were obtained from fecal samples, as well as virus sequences from the and Phylogenetic analysis showed that these viruses belonged to different genera, with multiple viruses clustered with other animal viruses. Whether they have pathogenicity and the ability to spread across species needs further study.
PubMed: 37389044
DOI: 10.1016/j.heliyon.2023.e17222 -
Scientific Reports Jun 2023Novel goose astrovirus (NGAstV) is a member of the genus Avain Avastrovirus (AAstV) and the family Astroviridae. NGAstV-associated gout disease has caused huge economic...
Novel goose astrovirus (NGAstV) is a member of the genus Avain Avastrovirus (AAstV) and the family Astroviridae. NGAstV-associated gout disease has caused huge economic losses to the goose industry worldwide. Since early 2020, NGAstV infections characterized by articular and visceral gout emerged continuously in China. Herein, we isolated a GAstV strain from goslings with fatal gout disease and sequenced its complete genome nucleotide sequence. Then we conducted systematic genetic diversity and evolutionary analysis. The results demonstrated that two genotypic species of GAstV (GAstV-I and GAstV-II) were circulating in China, and GAstV-II sub-genotype IId had become the dominant one. Multiple alignments of amino acid sequences of GAstV capsid protein revealed that several characteristic mutations (E456D, A464N, and L540Q) in GAstV-II d strains, as well as additional residues in the newly identified isolate which varied over time. These findings enrich the understanding of the genetic diversity and evolution of GAstV and may facilitate the development of effective preventive strategies.
Topics: Animals; Geese; Avastrovirus; Genomics; Arthritis, Gouty; Gout; China
PubMed: 37386083
DOI: 10.1038/s41598-023-37784-9 -
Microbial Pathogenesis Aug 2023Human astrovirus (HAstV) is an important causative agent of gastroenteritis in humans, which mainly infects young children and the elderly. The goal of this study was to... (Meta-Analysis)
Meta-Analysis Review
AIM
Human astrovirus (HAstV) is an important causative agent of gastroenteritis in humans, which mainly infects young children and the elderly. The goal of this study was to conduct a meta-analytic review of the prevalence of HAstV amongst patients with gastroenteritis, and to shed light on the connection between HAstV infection and gastroenteritis.
METHODS
Systematic literature searches were conducted to identify all potentially relevant studies recorded up to April 8th, 2022. For study weighting, the inverse variance method was employed and the random-effects model was applied to evaluate data. For case-control studies, the pooled odds ratio (OR) and 95% confidence interval (CI) were calculated to establish the relationship between HAstV infection and gastroenteritis.
RESULTS
Among 302423 gastroenteritis patients from 69 different countries, the overall pooled prevalence of HAstV infection was 3.48% (95% CI: 3.11%-3.89%). Case-control approach was used in 39 investigations, and the overall prevalence of HAstV infection among the 11342 healthy controls was 2.01% (95% CI: 1.40%-2.89%). Gastroenteritis and HAstV infection were associated with a pooled OR of 2.16 (95% CI: 1.72-2.71; P < 0.0001; I = 33.7%). The most commonly found HAstV genotypes in gastroenteritis patients were HAstV1 (62.18%), HAstV7 (33.33%), and HAstV-MLB1 (17.43%).
CONCLUSION
The frequency of HAstV infection was the highest in children under the age of five, and in developing countries. The prevalence rate of HAstV was not influenced by gender. Semi-nested and nested RT-PCR were highly sensitive assays for detecting HAstV infections.
Topics: Child; Humans; Infant; Child, Preschool; Aged; Mamastrovirus; Prevalence; Phylogeny; Feces; Gastroenteritis; Astroviridae Infections; Genotype
PubMed: 37385570
DOI: 10.1016/j.micpath.2023.106209 -
Viruses Jun 2023Astroviruses are small nonenveloped single-stranded RNA viruses with a positive sense genome. They are known to cause gastrointestinal disease in a broad spectrum of...
Astroviruses are small nonenveloped single-stranded RNA viruses with a positive sense genome. They are known to cause gastrointestinal disease in a broad spectrum of species. Although astroviruses are distributed worldwide, a gap in knowledge of their biology and disease pathogenesis persists. Many positive-sense single-stranded RNA viruses show conserved and functionally important structures in their 5' and 3' untranslated regions (UTRs). However, not much is known about the role of the 5' and 3' UTRs in the viral replication of HAstV-1. We analyzed the UTRs of HAstV-1 for secondary RNA structures and mutated them, resulting in partial or total UTR deletion. We used a reverse genetic system to study the production of infectious viral particles and to quantify protein expression in the 5' and 3' UTR mutants, and we established an HAstV-1 replicon system containing two reporter cassettes in open reading frames 1a and 2, respectively. Our data show that 3' UTR deletions almost completely abolished viral protein expression and that 5' UTR deletions led to a reduction in infectious virus particles in infection experiments. This indicates that the presence of the UTRs is essential for the life cycle of HAstV-1 and opens avenues for further research.
Topics: Humans; 3' Untranslated Regions; Mamastrovirus; Viral Proteins; Virus Replication; 5' Untranslated Regions; RNA, Viral
PubMed: 37376701
DOI: 10.3390/v15061402