Betaentomopoxvirus

Betaentomopoxvirus is a genus of viruses, in the family Poxviridae, in the subfamily Entomopoxvirinae. Lepidoptera and orthoptera insects serve as natural hosts. There are 16 species in this genus.

Taxonomy
The genus contains the following species:


 * Acrobasis zelleri entomopoxvirus
 * Adoxophyes honmai entomopoxvirus
 * Amsacta moorei entomopoxvirus
 * Arphia conspersa entomopoxvirus
 * Choristoneura biennis entomopoxvirus
 * Choristoneura conflicta entomopoxvirus
 * Choristoneura diversuma entomopoxvirus
 * Choristoneura fumiferana entomopoxvirus
 * Choristoneura rosaceana entomopoxvirus
 * Chorizagrotis auxiliaris entomopoxvirus
 * Heliothis armigera entomopoxvirus
 * Locusta migratoria entomopoxvirus
 * Mythimna separata entomopoxvirus
 * Oedaleus senegalensis entomopoxvirus
 * Operophtera brumata entomopoxvirus
 * Schistocerca gregaria entomopoxvirus

Structure
Viruses in Betaentomopoxvirus are enveloped, with ovoid geometries. The diameter is around 250 nm. Genomes are linear, around 225kb in length.

Life cycle
Viral replication is cytoplasmic. Entry into the host cell is achieved by attachment of the viral proteins to host glycosaminoglycans (GAGs) mediates endocytosis of the virus into the host cell. Fusion with the plasma membrane to release the core into the host cytoplasm. Early phase: early genes are transcribed in the cytoplasm by viral RNA polymerase. Early expression begins at 30 minutes post-infection. A Core is completely uncoated as early expression ends, the viral genome is now free in the cytoplasm. Intermediate phase: Intermediate genes are expressed, triggering genomic DNA replication at approximately 100 minutes post-infection. Late phase: Late genes are expressed from 140 min to 48 hours post-infection, producing all structural proteins. Assembly of progeny virions starts in cytoplasmic viral factories, producing a spherical immature particle. This virus particle matures into a brick-shaped intracellular mature virion (IMV). IMV virion can be released upon cell lysis, or can acquire a second double membrane from trans-Golgi and bud as external enveloped virion (EEV). Mature virion can be occluded in spheroids composed of spheroid in protein host receptors, which mediates endocytosis. Replication follows the DNA strand displacement model. DNA-templated transcription is the method of transcription. The virus exits the host cell by existing in occlusion bodies after cell death and remaining infectious until finding another host. Lepidoptera and orthoptera insects serve as the natural host.