8. Mpox Virus Replication Cycle
Poxvirus replication is distinct from that of other DNA viruses in that
it occurs in the cytoplasm of the host cell. Poxviruses enter cells by
an intricate mechanism that includes an attachment, hemifusion, and core
penetration within the plasma membrane, or via endocytosis41. The specific method that poxviruses employ to
enter cells is determined by their infectious form, which may either be
a mature virion (MV) through one outer membrane or an extracellular
enveloped virion (EV) with a different protein composition. In the EV
form, the membrane that is particularly EV-specific is eliminated,
preserving the underlying membrane affixed to the cell. EV is more
specialized for cell-to-cell transmission despite MV’s greater
prevalence because of its long, mobile projections made by the
polymerization of actin which adheres to the cell’s surface. When a
mature virion enters a cell, it loses its protective coating. Once
within the cell’s cytoplasm, the virus releases ready-made enzymes and
certain other enzymatic components that weaken the cell’s defences and
start the synthesis of its original genes.