Genetic Analysis of a Poliovirus/Hepatitis C Virus Chimera: New Structure for Domain II of the Internal Ribosomal Entry Site of Hepatitis C Virus
AUTOR(ES)
Zhao, Wei Dong
FONTE
American Society for Microbiology
RESUMO
Internal ribosomal entry sites (IRESs) of certain plus-strand RNA viruses direct cap-independent initiation of protein synthesis both in vitro and in vivo, as can be shown with artificial dicistronic mRNAs or with chimeric viral genomes in which IRES elements were exchanged from one virus to another. Whereas IRESs of picornaviruses can be readily analyzed in the context of their cognate genome by genetics, the IRES of hepatitis C virus (HCV), a Hepacivirus belonging to Flaviviridae, cannot as yet be subjected to such analyses because of difficulties in propagating HCV in tissue culture or in experimental animals. This enigma has been overcome by constructing a poliovirus (PV) whose translation is controled by the HCV IRES. Within the PV/HCV chimera, the HCV IRES has been subjected to systematic 5′ deletion analyses to yield a virus (P/H710-d40) whose replication kinetics match that of the parental poliovirus type 1 (Mahoney). Genetic analyses of the HCV IRES in P/H710-d40 have confirmed that the 5′ border maps to domain II, thereby supporting the validity of the experimental approach applied here. Additional genetic experiments have provided evidence for a novel structural region within domain II. Arguments that the phenotypes observed with the mutant chimera relate solely to impaired genome replication rather than deficiencies in translation have been dispelled by constructing novel dicistronic poliovirus replicons with the gene order [PV]cloverleaf-[HCV]IRES-Δcore-R-Luc-[PV]IRES-F-Luc-P2,3-3′NTR, which have allowed the measurement of HCV IRES-dependent translation independently from the replication of the replicon RNA.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=114863Documentos Relacionados
- Genetic Analysis of a Poliovirus/Hepatitis C Virus (HCV) Chimera: Interaction between the Poliovirus Cloverleaf and a Sequence in the HCV 5′ Nontranslated Region Results in a Replication Phenotype
- Poliovirus/Hepatitis C Virus (Internal Ribosomal Entry Site-Core) Chimeric Viruses: Improved Growth Properties through Modification of a Proteolytic Cleavage Site and Requirement for Core RNA Sequences but Not for Core-Related Polypeptides
- Poliovirus chimeras replicating under the translational control of genetic elements of hepatitis C virus reveal unusual properties of the internal ribosomal entry site of hepatitis C virus.
- An Enzymatic Footprinting Analysis of the Interaction of 40S Ribosomal Subunits with the Internal Ribosomal Entry Site of Hepatitis C Virus
- Tissue-Specific Replicating Capacity of a Chimeric Poliovirus That Carries the Internal Ribosome Entry Site of Hepatitis C Virus in a New Mouse Model Transgenic for the Human Poliovirus Receptor