poxvirus

Examples of poxvirus in the following topics:

• Double-Stranded DNA Viruses: Pox Viruses

  • The prototype of the poxvirus family is vaccinia virus, which has been used as a successful vaccine to eradicate smallpox virus.
  • The prototypic and most studied poxvirus, vaccinia virus (VACV), serves as an effective smallpox vaccine, a platform for recombinant vaccines against other pathogens, and an efficient gene expression vector for basic research.
  • The most abundant and simplest infectious form of the poxvirus particle, the mature virion (MV), consists of the viral DNA genome encased in a proteinaceous core and an outer lipoprotein membrane with approximately 60 and 25 associated viral proteins, respectively.
  • Following attachment to cell surfaces and fusion with the plasma or endosomal membrane, poxvirus replication is initiated by entry of the viral core into the cytoplasm, where all subsequent steps of the life cycle take place.
  • Poxvirus cores harbor the viral DNA-dependent RNA polymerase and transcription factors necessary for expression of early genes, which constitute nearly half of the viral genome and encode proteins needed for DNA replication and intermediate gene transcription, as well as a large number of immunomodulators.

• Replication of Double-Stranded DNA Viruses of Animals

  • This is the Poxvirus family, which comprises highly pathogenic viruses that infect vertebrates.
  • The replication of poxvirus is unusual for a virus with double-stranded DNA genome (dsDNA) because it occurs in the cytoplasm, although this is typical of other large DNA viruses.
  • Poxvirus encodes its own machinery for genome transcription, a DNA dependent RNA polymerase, which makes replication in the cytoplasm possible.

• Discovery and Detection of Viruses

  • Unlike bacteria (which are about 100 times larger), we cannot see viruses with a light microscope, with the exception of some large virions of the poxvirus family.