Virus Genes最新文献

Influenza A viruses continue to pose a serious threat to public health and economic stability. To investigate the role of C1RL-AS1 in influenza A virus (IAV) pneumonia. Using RT-qPCR analysis, we determined C1RL-AS1 expression levels in children with IAV-infected pneumonia and A549 cells. C1RL-AS1 expression levels in children were subjected to ROC analysis. C1RL-AS1 was knocked down to investigate its role in IAV-infected A549 cells, including effects on viral nucleoprotein (NP) production, cell survival, and apoptosis. Downstream miRNAs of C1RL-AS1 were predicted and validated. MiR-16-5p target genes were predicted and validated. C1RL-AS1 was up-regulated in IAV-infected children and A549 cells. C1RL-AS1 expression levels distinguished children with IAV pneumonia from healthy children. Knockdown of C1RL-AS1 attenuated viral NP production, promoted A549 cell survival, and inhibited apoptosis. MiR-16-5p was a downstream C1RL-AS1 miRNA. miR-16-5p counteracted the anti-IAV infection effect brought about by C1RL-AS1 knockdown. LAMP3 was a miR-16-5p target gene associated with pneumonia. LAMP3 restored the cellular effects brought about by C1RL-AS1/miR-16-5p co-knockdown. C1RL-AS1 is a possible diagnostic factor for IAV pneumonia in children. C1RL-AS1 may participate in IAV pneumonia by sponging miR-16-5p and then moderating LAMP3.

Researchers have identified Avastrovirus as a significant genus of bird viruses, linked to various avian diseases such as enteritis, growth retardation, nephritis and hepatitis. These infections can cause substantial economic losses in agrocultureand have a widespread impact on global food production. Although there have been numerous studies on these viruses, most of them-mainly focuses on poultry. Research on astroviruses in wild bird populations has revealed a wide genetic diversity of these viruses, yet our understanding of their biological and ecological characteristics remains limited. In this study, we for the first time detected avastrovirus in wild migratory birds of the families Anatidae and Columbidae from Sakhalin Island, North Pacific Ocean. Phylogenetic analysis revealed the presence of Avastrovirus 2 in wild doves and Avastrovirus 3 in wild ducks. These findings provide valuable insights into the circulation of astroviruses in wild bird populations of Sakhalin Island, which lies along the East Asian-Australasian Flyway.

Previous studies showed that deletion of the viral thymidine kinase (TK) gene in several alphaherpesviruses including EHV-1 reduced their virulence. Previously, we found that deletion of ORF37, which is located head-to-head with TK, decreased EHV-1 virulence in mice but did not affect the expression of TK mRNA. Therefore, deletion of ORF38 might also affect virulence by partially deleting the ORF37 promoter. To investigate the role of the TK gene-encoding region in the pathogenesis of EHV-1 as well as the expression of ORF37, we generated a TK deletion mutant by using a bacterial artificial chromosome carrying the neuropathogenic strain Ab4p. Deletion of TK increased the transcription of ORF37, did not cause any neurological disorders in CBA/N1 mice, and its growth in cultured neural cells was impaired. These results suggest deletion of ORF38 does not affect the ORF37 promoter and confirm that TK plays an important role in the neuropathogenicity of EHV-1.

A novel double-stranded RNA virus, designated as "Magnaporthe oryzae polymycovirus 1" (MoPmV1), was identified in Magnaporthe oryzae strain TM02. MoPmV1 has four dsRNA fragments, ranging from 1324 to 2401 bp in length. DsRNA1, 2, and 3 of MoPmV1 each possess a single large open reading frame (ORF), whereas dsRNA4 contains two ORFs. BLASTp analysis indicated that ORF1a, encoded by dsRNA1, shows 59.2% amino acid sequence identity with the RNA-dependent RNA polymerase (RdRp) of Beauveria bassiana polymycovirus 2; ORF2a, encoded by dsRNA2, shows 42.3% identity with the putative serine protease of Phaeoacremonium minimum tetramycovirus 1; ORF3a, encoded by dsRNA3, shows 40.6% identity with the methyltransferase of Aspergillus fumigatus tetramycovirus 1; ORF4a, encoded by dsRNA4, shows 41.7% identity with the proline-alanine-serine-rich (PASr) protein of Botryosphaeria dothidea virus 1, while ORF4b, encoded by dsRNA4, shows no significant similarity to any known proteins. Phylogenetic analysis of the RdRp domain indicated that MoPmV1 was grouped in a cluster with members of the genus Polymycovirus in the family Polymycoviridae. Based on these characteristics, MoPmV1 is a new member of the genus Polymycovirus in the family Polymycoviridae. This is the first report of a mycovirus of the family Polymycoviridae identified in rice blast fungus M. oryzae.

Phylogenetic analysis based on whole-genome sequences is the gold standard for monkeypox virus (MPXV) phylogeny. However, genomic epidemiology capability and capacity are lacking or limited in resource poor countries of sub-Saharan Africa. Therefore, these make real-time genome surveillance of MPXV virtually impossible. We hypothesized that phylogenetic analysis based on single, conserved genes will produce phylogenetic tree topology consistent with MPXV whole-genome phylogeny, thus serving as a reliable proxy to phylogenomic analysis. In this study, we analyzed 62 conserved MPXV genes and showed that Bayesian phylogenetic analysis based on five genes (OPG 066/E4L, OPG068/E6R, OPG079/I3L, OPG145/A18R, and OPG150/A23R) generated phylogenetic trees with 72.2-96.3% topology similarity index to the reference phylogenomic tree topology. Our results showed that phylogenetic analysis of the identified five genes singly or in combination can serve as surrogate for whole-genome phylogenetic analysis, and thus obviates the need for whole-genome sequencing and phylogenomic analysis in regions where genomic epidemiology competence and capacity are lacking or unavailable. This study is relevant to evolution and genome surveillance of MPXV in resource limited countries.

Hepatitis B virus (HBV) infection remains a significant global health challenge, with chronic HBV leading to severe liver diseases, including cirrhosis and hepatocellular carcinoma. Current treatments often fail to eradicate the virus, highlighting the need for innovative therapeutic strategies. The CRISPR/Cas9 system has emerged as a dynamic tool for precise genome editing and presents a promising approach to targeting and eliminating HBV infection. This review provides a comprehensive overview of the advances, challenges, and delivery strategies associated with CRISPR/Cas9-based therapies for HBV. We begin by elucidating the mechanism of the CRISPR/Cas9 system and then explore HBV pathogenesis, focusing on the role of covalently closed circular DNA (cccDNA) and integrated HBV DNA in maintaining chronic infection. CRISPR/Cas9 can disrupt these key viral reservoirs, which are critical for persistent HBV replication and associated liver damage. The application of CRISPR/Cas9 in HBV treatment faces significant challenges, such as off-target effects, delivery efficiency, and immune responses. These challenges are addressed by examining current approaches to enhance the specificity, safety, and efficacy of CRISPR/Cas9. A future perspective on the development and clinical translation of CRISPR/Cas9 therapies for HBV is provided, emphasizing the requirement for further research to improve delivery methods and ensure durable safety and effectiveness. This review underscores the transformative potential of CRISPR/Cas9 in combating HBV and sets the stage for future breakthroughs in the field.

Messenger ribonucleic acid (mRNA) was discovered in 1961 as an intermediary for transferring genetic information from DNA to ribosomes for protein synthesis. The COVID-19 pandemic brought worldwide attention to mRNA vaccines. The emergency use authorization of two COVID-19 mRNA vaccines, BNT162b2 and mRNA-1273, were major achievements in the history of vaccine development. Lipid nanoparticles (LNPs), one of the most superior non-viral delivery vectors available, have made many exciting advances in clinical translation as part of the COVID-19 vaccine and therefore has the potential to accelerate the clinical translation of many gene drugs. In addition, due to these small size, biocompatibility and excellent biodegradability, LNPs can efficiently deliver nucleic acids into cells, which is particularly important for current mRNA therapeutic regimens. LNPs are composed cationic or pH-dependent ionizable lipid bilayer, polyethylene glycol (PEG), phospholipids, and cholesterol, represents an advanced system for the delivery of mRNA vaccines. Furthermore, optimization of these four components constituting the LNPs have demonstrated enhanced vaccine efficacy and diminished adverse effects. The incorporation of biodegradable lipids enhance the biocompatibility of LNPs, thereby improving its potential as an efficacious therapeutic approach for a wide range of challenging and intricate diseases, encompassing infectious diseases, liver disorders, cancer, cardiovascular diseases, cerebrovascular conditions, among others. Consequently, this review aims to furnish the scientific community with the most up-to-date information regarding mRNA vaccines and LNP delivery systems.

Post-translational modifications (PTMs), as epigenetic modifications, are significant in the interaction between virus and its host. However, it is unclear whether rotavirus (RV) causes changes in both the host cell epigenetic protein modification and the regulatory mechanism of viral replication. Here, we analyzed the proteome of Caco-2 cells to determine if acetylation modification occurred within the cells after RV infection. We found that glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a protein involved in glycolysis, was deacetylated at lysine 219 via histone deacetylase 9 (HDAC9) in 50 h after the RV infection. Remarkably, the deacetylation of GAPDH promoted RV replication. Finally, we found that glycolysis was alterable in Caco-2 cells by RV or the deacetylation of GAPDH lysine 219, using the Seahorse XF Glycolysis Stress Test. In conclusion, our results demonstrate for the first time that RV infection promoted deacetylation of GAPDH at lysine 219 in order to increase its own viral replication in Caco-2 cells.

Porcine epidemic diarrhea virus (PEDV) small envelope protein (E) plays important roles in virus budding, assembly, and release. Our previous study found that PEDV E protein localizes in the endoplasmic reticulum (ER) to trigger the unfolded protein response (UPR). However, how UPR is directly regulated by PEDV E protein remains elusive. Thus, in this study, we investigated the expression of ER chaperone glucose-regulated protein 78 (GRP78) and activations of the three main UPR signaling pathways to elucidate the underlying mechanisms of UPR triggered by PEDV E protein. The results showed that over-expression of PEDV E protein increased expression of GRP78 and induced stronger phosphorylation of both protein kinase RNA-like ER kinase (PERK) and eukaryotic initiation factor-2α (eIF2α), as well as caused the significant degradation of activating transcription factor 6 (ATF6), in both dose- and time-dependent manners. However, PEDV E protein did not induce UPR through the inositol-requiring enzyme 1 (IRE1) signaling pathway, as revealed by the splicing of XBP1 remaining unaffected and unchanged when PEDV E protein was overexpressed. Taken together, these results demonstrate that PEDV E protein induces UPR through activation of both PERK and ATF6 pathways rather than IRE1 signaling. This study not only provides mechanistic details of UPR induced by the PEDV E protein, but also provides insights into these new biologic functions to help us better understand the interactions between PEDV and host cells.

Autographa californica nucleopolyhedrovirus orf89 (vp39) encodes the major capsid protein VP39. Multiple alignments of protein sequences showed that VP39 has 8 conserved cysteine (Cys) residues. Cysteine residues play an important role in proper function of a protein. To determine the importance of these conserved cysteine residues for virus proliferation, a series of recombinant viruses harboring VP39-Cys mutants were constructed. Viral growth curves and transmission electron microscopy showed that mutation of Cys29, Cys132, Cys169, Cys229, or Cys232 of VP39 to alanine did not affect budded virion production; however, the mutation of Cys18, Cys36, or Cys49 to alanine resulted in interruption of capsid assembly. Co-immunoprecipitation assays showed that mutations of these 8 cysteines individually or simultaneously had no effect on self-association of VP39. Immunofluorescence analysis by confocal microscopy revealed that the subcellular localization of VP39 with mutations in Cys18, Cys36 or Cys49 was exclusively distributed in the cytoplasm of a cell regardless of virus infection or not, while the wild-type VP39 or the VP39 carrying mutations in Cys29, Cys132, Cys169, Cys229, or Cys232 was distributed throughout the cytoplasm and the nucleus. Our results demonstrated that Cys18, Cys36, and Cys49 are essential for the proper localization of VP39, which is a prerequisite for successful nucleocapsid assembly of the virus.