Figure 3: Replication cycle of Poxvirus
Then, early messenger RNA is made via the viral DNA-dependent polymerase
(mRNA). The uncoating process that follows DNA replication, and the
creation of intermediary transcriptional regulators are both supported
by early mRNA translation. The intermediate mRNA is then translated and
expressed in late mRNAs, where it is converted into structural and
non-structural proteins 42. Then, translated proteins
and DNA concatemers generated during the initial stages of replication
are assembled. They then transform becoming immature virions, which
mature into intracellular viruses (IMVs). Since IMVs are devoid of an
outer membrane, they can only spread when cells are damaged.
Intracellular enveloped virions (IEVs) are formed from IMV particles
that do not wrap completely in the cytoplasmic protein matrix. These
cells are aided in reaching the cell membrane by microtubules. They then
combine with the cell membrane to generate cell-associated viruses
(CEVs), that lead to actin polymerization and the production of
filaments, which help to facilitate CEV evacuation from the cell. Both
extracellular and intracellular viral pathogens have a significant
impact on pathogenesis (Figure 3) . The primary means of disease
transmission from one cell to the next are intracellular viral virions
(IMV and IEV), together with CEVs. EEVs are necessary for viral spread
within an affected organism 43.