Biomaterial Database

Conversion of VP1 to VPg in cells infected by infectious pancreatic necrosis virus. 1998

G Magyar, and H K Chung, and P Dobos

Department of Biology, Konkuk University, Seoul, Korea.

The RNA polymerase VP1 of IPNV (a bisegmented dsRNA containing virus) is present in the virion both as a free polypeptide and as a genome-linked protein (VPg). Virion VP1 primes viral RNA synthesis in vitro (P. Dobos, 1995, Virology 208, 19-25), and here we present data which suggest that protein-primed RNA synthesis may also take place in infectious pancreatic necrosis virus (IPNV)-infected cells. Anti-VP1 serum immunoprecipitated several polypeptides larger than the 94-kDa VP1 of IPNV from [35S]methionine-labeled infected cell lysates. During denaturing, SDS-polyacrylamide gel electrophoresis these polypeptides formed a characteristic "ladder" which was resistant to alkaline phosphatase but sensitive to RNases, indicating that it consisted of VP1 polypeptides with oligoribonucleotides of various lengths attached to them. Probing the ladder with 5' and 3' end-specific, as well as plus-, or minus-strand-specific oligonucleotides revealed that they represent VP1 linked to 5' terminal sequences of genome segment A- and B-specific plus strands. Pulse-chase experiments in combination with two-dimensional polyacrylamide gel electrophoresis revealed that labeled VP1 could be chased to replicative intermediate, to ssRNA, to dsRNA, and eventually to virion VPg-dsRNA and that VP1 could be released from all these structures by RNase treatment. We suggest that these results are most compatible with the model where a VP1-pN structure acts as a primer for viral RNA synthesis in vivo, a mechanism that has been shown to occur in vitro.

UI	MeSH Term	Description	Entries
D005814	Genes, Viral	The functional hereditary units of VIRUSES.	Viral Genes,Gene, Viral,Viral Gene
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012321	DNA-Directed RNA Polymerases	Enzymes that catalyze DNA template-directed extension of the 3'-end of an RNA strand one nucleotide at a time. They can initiate a chain de novo. In eukaryotes, three forms of the enzyme have been distinguished on the basis of sensitivity to alpha-amanitin, and the type of RNA synthesized. (From Enzyme Nomenclature, 1992).	DNA-Dependent RNA Polymerases,RNA Polymerases,Transcriptases,DNA-Directed RNA Polymerase,RNA Polymerase,Transcriptase,DNA Dependent RNA Polymerases,DNA Directed RNA Polymerase,DNA Directed RNA Polymerases,Polymerase, DNA-Directed RNA,Polymerase, RNA,Polymerases, DNA-Dependent RNA,Polymerases, DNA-Directed RNA,Polymerases, RNA,RNA Polymerase, DNA-Directed,RNA Polymerases, DNA-Dependent,RNA Polymerases, DNA-Directed
D014158	Transcription, Genetic	The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.	Genetic Transcription
D014758	Viral Core Proteins	Proteins found mainly in icosahedral DNA and RNA viruses. They consist of proteins directly associated with the nucleic acid inside the NUCLEOCAPSID.	Core Proteins, Viral,Major Core Protein,Major Core Proteins, Viral,Adenovirus Core Protein VII,Core Protein V,Core Protein lambda 2,Influenza Virus Core Proteins,Major Core Protein lambda 1,Major Core Protein lambda-1,Major Core Protein sigma 2,Major Core Protein sigma-2,OVP 19,Oncornaviral Protein P19,P30 Core Proteins,Viral Protein P19,Virus Core Proteins,Core Protein, Major,Core Proteins, P30,Core Proteins, Virus,Protein P19, Oncornaviral,Protein P19, Viral,Protein, Major Core,Proteins, P30 Core,Proteins, Viral Core,Proteins, Virus Core
D014779	Virus Replication	The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.	Viral Replication,Replication, Viral,Replication, Virus,Replications, Viral,Replications, Virus,Viral Replications,Virus Replications
D015678	Viral Structural Proteins	Viral proteins that are components of the mature assembled VIRUS PARTICLES. They may include nucleocapsid core proteins (gag proteins), enzymes packaged within the virus particle (pol proteins), and membrane components (env proteins). These do not include the proteins encoded in the VIRAL GENOME that are produced in infected cells but which are not packaged in the mature virus particle,i.e. the so called non-structural proteins (VIRAL NONSTRUCTURAL PROTEINS).	Polypeptide VP1, Structural,VP(1),VP(2),VP(3),VP(6),VP(7),Viral Structural Proteins VP,Virus Structural Proteins,Proteins, Viral Structural,Proteins, Virus Structural,Structural Polypeptide VP1,Structural Proteins, Viral,Structural Proteins, Virus,VP1, Structural Polypeptide
D015967	Gene Expression Regulation, Viral	Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses.	Regulation of Gene Expression, Viral,Viral Gene Expression Regulation,Regulation, Gene Expression, Viral
D018061	Infectious pancreatic necrosis virus	The type species of AQUABIRNAVIRUS, causing infectious pancreatic necrosis in salmonid fish and other freshwater and marine animals including mollusks.	IPNV,Pancreatic Necrosis Virus, Infectious
D018175	Birnaviridae Infections	Virus diseases caused by the BIRNAVIRIDAE.	Infections, Birnaviridae,Birnaviridae Infection,Infection, Birnaviridae