疾病及处理

Of the many primer combinations that we have investigated for the detection of avian coronaviruses, two have worked better than any of the others: they worked with the largest number of strains/samples of a given coronavirus and the most species of avian coronavirus, and they also produced the most ...

A remarkably conserved 43-nucleotide-long motif present at the 3′-end of the genomes of several members of the polyadenylated RNA virus families Astroviridae, Coronaviridae, and Picornaviridae can be used for the detection and sequence characterization of the viruses harboring i ...

The zoonotic transmission of SARS coronavirus from animals to humans revealed the potential impact of coronaviruses on mankind. This incident also triggered several surveillance programs to hunt for novel coronaviruses in human and wildlife populations. Using classical RT-PCR ...

The recent discoveries of novel human coronaviruses, including the coronavirus causing SARS, and the previously unrecognized human coronaviruses HCoV-NL63 and HCoV-HKU1, indicate that the family Coronaviridae harbors more members than was previously assumed. All human coro ...

Since the advent of efficient cell-culture methods for HCV replication and, more recently, infection, there has been a need to efficiently sequence the viral RNA in these systems. This need is especially urgent in light of the error-prone nature of HCV RNA replication, which leads to a variety of int ...

Subgenomic replicons have been the first efficient cell-culture system for HCV and still are a valuable tool for studying different aspects of RNA replication. A variety of replicons based on different viral isolates and vector designs have been established. Here, I give a brief overview of vi ...

RNA replication of HCV occurs in the multiprotein complexes associated with the endoplasmic reticular (ER) membranes. The HCV NS3 to NS5B proteins are necessary and sufficient for HCV RNA replication in the cell, but cellular proteins in the HCV replication complex (RC) have not been determi ...

HCV replication complexes are well-organized protein and lipid structures responsible for HCV RNA replication. The nonstructural protein NS5B, an RNA-dependent RNA polymerase, is the catalytic subunit of these replication complexes. After being isolated from HCV replicon-c ...

Formation of a membrane-associated replication complex, composed of viral proteins, replicating RNA, altered cellular membranes, and other host factors, is a hallmark of all positive-strand RNA viruses. In the case of HCV, RNA replication takes place in a likely endoplasmic reticulum– ...

Interferon regulatory factor 3 (IRF-3) is a ubiquitously expressed latent cellular transcription factor that plays a pivotal role in control of innate, type I interferon (IFN) antiviral responses. After viral infections, IRF-3 is activated by specific C-terminal phosphorylation, ...

Because HCV RNA-dependent RNA polymerase is error-prone and the viral RNA has a high turnover rate, the genetic diversity of HCV is very high both in vitro and in vivo. The mutation rate in long-term replicon cultures approaches 3.0 � 10-3 base substitutions/site/year in this in vitro replication mo ...

Efforts to find effective treatment for hepatitis C virus (HCV) have been hampered by the lack of a robust in vitro infectious tissue-culture system for this virus. A subgenomic replicon system was first developed in 1999 and has since been extensively optimized to accommodate the need for conv ...

Small interfering RNAs (siRNAs) and short hairpin RNAs (shRNAs) have been reported to suppress gene expression significantly. HCV seems a suitable candidate for targets of siRNAs, as HCV is a positive single-strand RNA virus and replicates in the cytoplasm. Efficient inhibition by siRNAs ...

NS5A phosphorylation can be studied in two ways: in living cells and in vitro. The former has several advantages: NS5A phosphorylation takes place in a cellular background and therefore might mimic more closely the real in vivo situation. Viral proteins and cellular kinases are in the correct ce ...

The NS5A protein of HCV is an essential component of the viral RNA replication machinery and may also function in modulation of the host cell environment. The exact function of NS5A in these processes remains unknown. NS5A is a large hydrophilic phosphoprotein protein consisting of three doma ...

HCV is a small positive-strand RNA virus responsible for a considerable proportion of acute and chronic hepatitis in humans. Although all HCV enzymes are, in theory, equally appropriate for therapeutic intervention, the NS3-NS4A serine protease and the NS5B RNA-dependent RNA polymer ...

After attachment to specific receptors on the surfaces of target cells, hepatitis C virus (HCV) particles are thought to be internalized to endosomes, where low pH induces fusion between the viral and cellular membranes, delivering the HCV genome into the cytoplasm. Here, we describe methods ...

HCV infection leads in 50 to 80% of cases to chronic hepatitis, liver cirrhosis, or hepatocellular carcinoma. Interferons and the nucleoside analog ribavirin form the basis for treatment but are not sufficiently effective and have numerous side effects. Although about 300 million people ...

This provides a brief introduction into the mechanism of DNA replication by the E1 and E2 proteins and describes the traditional Southern blotting technique that is used to monitor E1- and E2-mediated DNA replication. It also includes a novel real-time polymerase chain reaction (PCR) appro ...

Heterologous gene expression is often treated empirically and a number of host organisms are systematically tested. Early successes in the expression of recombinant proteins were achieved using the well-studied bacterium Escherichia coli (1). This prokaryotic expression sys ...