How does the polio virus replicate?
How does the polio virus replicate?
The replication cycle of poliovirus is initiated by binding to the cell surface receptor CD155 (1). The virion forms a pore in the cell membrane through which viral RNA is released into the cytoplasm (2). Translation of the viral RNA occurs by an IRES-mediated mechanism (3).
What is the structure of the polio virus?
Polioviruses are single-stranded RNA viruses belonging to the family Picornaviridae. They have a naked protein capsid with a dense central core. The capsid consists of four structural proteins, VP1, VP2, VP3, and VP4. The genomic RNA is approximately 7440 to 7500 nucleotides in length.
How is DNA replicated in a virus?
DNA viruses replicate their genomes using DNA polymerase enzymes and transcribe their mRNA using DNA-dependent RNA polymerase enzymes.
Is polio vaccine RNA or DNA?
Genomic structure of strains for Vero cell vaccines Poliovirus has a single-stranded RNA genome translated as polyprotein – the four capsid proteins which determine serotype and antigenic structure and are derived from the P1 gene.
Is polio virus lytic or lysogenic?
One such virus, poliovirus (PV), is an extremely lytic RNA virus that requires the expression of CD155, the poliovirus receptor (PVR), for infection.
What is the pathogenesis of polio?
During intestinal replication, the virus invades local lymphoid tissue and may enter the bloodstream, and then infect cells of the central nervous system. Poliovirus-induced destruction of motor neurons of the anterior horn of the spinal cord and brain stem cells results in distinctive paralysis.
What type of virus is poliovirus?
Polioviruses are small single-stranded RNA viruses that belong to the Enterovirus subgroup of the family Picornaviridae. Humans are the only reservoir for polio virus.
How many atoms are in polio virus?
He fed data on the structure of the 240 proteins and 60 lipids from which the virus is constructed into a supercomputer. And it put together the virus in a simulated water environment – a jigsaw of more than 3.6 million atoms of which the virus comprised only 900,000.
What are the 5 steps of virus replication?
Main steps of viral replication These include attachment, penetration, uncoating, replication, assembly, and virion release. The first stage, attachment, involves viral proteins binding to the host cell surface. There, they interact with receptors specific to them and their host cells.
Where does DNA replication occur in a virus?
Most double-stranded DNA viruses replicate within the host cell nucleus, including polyomaviruses, adenoviruses, and herpesviruses—poxviruses, however, replicate in the cytoplasm.
How is DNA used in vaccines?
DNA vaccines work by injecting genetically engineered plasmid containing the DNA sequence encoding the antigen(s) against which an immune response is sought, so the cells directly produce the antigen, thus causing a protective immunological response.
What is an RNA virus vs DNA virus?
The genetic material of a virus can be either DNA or RNA. The viruses that contain DNA as their genetic material are called the DNA viruses. RNA viruses, on the other hand, contain RNA as their genetic material. DNA viruses are mostly double-stranded while RNA viruses are single-stranded.