Archives of Virology最新文献

Upregulation of ADAMTS-4 has been reported to have an important role in lung injury, and ADAMTS-4 expression is regulated by miR-126a-5p in abdominal aortic aneurysms. The aim of this study was to investigate whether miR-126a-5p/ADAMTS-4 plays a role in influenza-virus-induced lung injury. Lung fibroblasts were infected with H1N1 influenza virus to detect changes in miR-126a-5p and ADAMTS-4 expression, and cell viability was measured by CCK-8 assay. Inflammatory factors and matrix protease levels were examined using ELISA kits, and cell apoptosis was assessed by measuring the levels of apoptosis-related proteins. A dual luciferase assay was used to verify the regulatory relationship between miR-126a-5p and ADAMTS-4. H1N1 influenza virus reduced fibroblast viability, inhibited miR-126a-5p expression, and promoted ADAMTS-4 expression. Overexpression of miR-126a-5p attenuated the cellular inflammatory response, apoptosis, matrix protease secretion, and virus replication. Luciferase reporter assays revealed that miR-126a-5p inhibited ADAMTS-4 expression by targeting ADAMTS-4 mRNA. Further experiments showed that overexpression of ADAMTS-4 significantly reversed the inhibitory effects of miR-126a-5p on fibroblast inflammation, apoptosis, matrix protease secretion, and virus replication. Upregulation of miR-126a-5p inhibits H1N1-induced apoptosis, inflammatory factors, and matrix protease secretion, as well as virus replication in lung fibroblasts.

Using a high-throughput sequencing (HTS) approach, we report the discovery of a new alphasatellite identified in a winter barley plant collected in France in 2022 that was also infected by wheat dwarf virus (WDV). The presence of the satellite and of WDV was confirmed by several independent PCR assays, and the complete genome sequence was determined. The circular satellite genome is 1424 nt long and shows typical hallmarks of members of the subfamily Geminialphasatellitinae, including a replication-associated hairpin with a CAGTATTAC sequence and a Rep-encoding open reading frame (ORF). It also possesses a second ORF, embedded in a different frame within the Rep ORF, which is also observed in clecrusatellites and a few other members of the family Alphasatellitidae. Pairwise sequence comparisons and phylogenetic analysis showed that this satellite represents a novel species. Its closest relatives are in the genus Colecusatellite, but it likely represents a new genus given its divergence from other genera of the subfamily Geminialphasatellitinae. Given that WDV was the only virus observed in coinfection with the satellite, the name "wheat dwarf virus-associated alphasatellite" is proposed for this novel agent.

Here, we report a novel ourmia-like mycovirus, named “Phomopsis asparagi magoulivirus 1” (PaMV1), derived from the phytopathogenic fungus Phomopsis asparagi. The genome of PaMV1 consists of a positive-sense single-stranded RNA (+ ssRNA) that is 2,639 nucleotides in length, with a GC content of 57.13%. It contains a single open reading frame (ORF) encoding a putative RNA-dependent RNA polymerase (RdRp) consisting of 686 amino acids with a molecular mass of 78.57 kDa. Phylogenetic analysis based on RdRp sequences revealed that PaMV1 grouped together with Diaporthe gulyae magoulivirus 1 (DgMV1) in a distinct clade. Sequence comparisons and phylogenetic analysis suggest that PaMV1 is a novel member of the genus Magoulivirus, family Botourmiaviridae.

A novel monopartite dsRNA virus, tentatively named “sponge gourd amalgavirus 1” (SGAV1), was discovered by high-throughput sequencing in sponge gourd (Luffa cylindrica) displaying mosaic symptoms in Jiashan County, Zhejiang Province, China. The genome of SGAV1 is 3,447 nucleotides in length and contains partially overlapping open reading frames (ORFs) encoding a putative replication factory matrix-like protein and a fusion protein, respectively. The fusion protein of SGAV1 shares 57.07% identity with the homologous protein of salvia miltiorrhiza amalgavirus 1 (accession no. DAZ91057.1). Phylogenetic analysis based on the RNA-dependent RNA polymerase (RdRp) protein suggests that SGAV1 belongs to the genus Amalgavirus of the family Amalgaviridae. Moreover, analysis of SGAV1-derived small interfering RNAs indicated that SGAV1 was actively replicating in the host plant. Semi-quantitative RT-PCR showed higher levels of SGAV1 expression in leaves than in flowers and fruits. This is the first report of a novel amalgavirus found in sponge gourd in China.

In this study, we identified a novel partitivirus, named "Cordyceps militaris partitivirus 1" (CmPV1), in Cordyceps militaris strain RCEF7506. The complete genome of CmPV1 comprises two segments, dsRNA1 and dsRNA2, each encoding a single protein. dsRNA1 (2,206 bp) encodes an RNA-dependent RNA polymerase (RdRp), and dsRNA2 (2,256 bp) encodes a coat protein (CP). Sequence analysis revealed that dsRNA1 has the highest similarity to that of Bipolaris maydis partitivirus 2 (BmPV2), whereas dsRNA2 shows the highest similarity to human blood-associated partitivirus (HuBPV). Phylogenetic analysis based on RdRp sequences suggests that CmPV1 is a new member of the genus Betapartitivirus of the family Partitiviridae. This is the first documentation of a betapartitivirus infecting the entomopathogenic fungus C. militaris.

Viruses use various strategies and mechanisms to deal with cells and proteins of the immune system that form a barrier against infection. One of these mechanisms is the encoding and production of viral microRNAs (miRNAs), whose function is to regulate the gene expression of the host cell and the virus, thus creating a suitable environment for survival and spreading viral infection. miRNAs are short, single-stranded, non-coding RNA molecules that can regulate the expression of host and viral proteins, and due to their non-immunogenic nature, they are not eliminated by the cells of the immune system. More than half of the viral miRNAs are encoded and produced by Orthoherpesviridae family members. Human cytomegalovirus (HCMV) produces miRNAs that mediate various processes in infected cells to contribute to HCMV pathogenicity, including immune escape, viral latency, and cell apoptosis. Here, we discuss which cellular and viral proteins or cellular pathways and processes these mysterious molecules target to evade immunity and support viral latency in infected cells. We also discuss current evidence that their function of bypassing the host’s innate and adaptive immune system is essential for the survival and multiplication of the virus and the spread of HCMV infection.

The highly pathogenic genotype 2b (HP-G2b) of porcine epidemic diarrhea virus (PEDV), which caused a pandemic in 2013–2014, evolved in South Korea and became endemic, affecting the domestic pig industry. This study describes the genotypic traits of novel HP-G2b PEDV strains identified on affected farms experiencing low disease severity with < 10% neonatal mortality. Nucleotide sequencing revealed common deletion patterns, termed S-DEL2, resulting in a two-amino-acid deletion at positions 60 and 61, 61 and 62, or 63 and 64 in the N-terminal domain of the spike (S) protein of all isolates. The S barcode profiles of S-DEL2 variants differed from each other and shared 96.0–99.4% and 98.5–99.6% nt sequence identity with other South Korean HP-G2b PEDV strains in the S gene and in the complete genome sequence, respectively. Genetic and phylogenetic analysis showed that the S-DEL2 strains belonged to diverse domestic clades: CK, CK.1, CK.2, or NC. The emergence of novel S-DEL2 strains suggests that continuous evolution of PEDV occurs under endemic circumstances, resulting in genetic diversity and distinct clinical presentations. This study advances our knowledge regarding the genetic and pathogenic heterogeneity of PEDV and emphasizes the importance of active monitoring and surveillance to identify novel variants and determine their genotypic and phenotypic characteristics.

Infections caused by multidrug-resistant (MDR) bacteria are a growing global concern. Enterobacter cloacae complex (ECC) species are particularly adept at developing antibiotic resistance. Phage therapy is proposed as an alternative treatment for pathogens that no longer respond to antibiotics. Unfortunately, ECC phages are understudied when compared to phages of many other bacterial species. In this Ghanaian-Finnish study, we isolated two ECC strains from ready-to-eat food samples and three novel phages from natural waters against these strains. We sequenced the genomic DNA of the novel Enterobacter phages, fGh-Ecl01, fGh-Ecl02, and fGh-Ecl04, and assessed their therapeutic potential. All of the phages were found to be lytic, easy to propagate, and lacking any toxic, integrase, or antibiotic resistance genes and were thus considered suitable for therapy purposes. They all were found to be related to T4-type viruses: fGh-Ecl01 and fGh-Ecl04 to karamviruses and fGh-Ecl02 to agtreviruses. Testing of Finnish clinical ECC strains showed promising susceptibility to these novel phages. As many as 61.1% of the strains were susceptible to fGh-Ecl01 and fGh-Ecl04, and 7.4% were susceptible to fGh-Ecl02. Finally, we investigated the susceptibility of the newly isolated ECC strains to three antibiotics – meropenem, ciprofloxacin, and cefepime – in combination with the novel phages. The use of phages and antibiotics together had synergistic effects. When using an antibiotic-phage combination, even low concentrations of antibiotics fully inhibited the growth of bacteria.

Given the high prevalence of avian leukosis virus subgroup K (ALV-K) in chickens in China, the positive rate of ALV-K in local chickens in Henan province was investigated, and the genetic region encoding the glycoprotein gp85 of isolates from positive chickens was analyzed. The positive rate of ALV-K in local chickens in Henan was found to be 87.2% (41/47). Phylogenetic analysis of gp85 sequences revealed six clusters that differed in their host range regions (hr1 and hr2) and variable regions (vr1, vr2, and vr3). Evidence of recombination of hr1, hr2, vr1, vr2, and vr3 was observed between the different clusters. The isolate HN23LS02 appears to have obtained its hr1 and hr2 regions from separate lineages via recombination but without having a significant affect on the replication capacity of the virus.