- Viruses can only replicate inside viable host cells.
- General strategy is to use the host cell enzymes to replicate and translate viral DNA, therefore making new virus particles, which burst out of the cell.
- There are two main mechanisms
- The virus attaches to the host cell membrane. This stimulates endocytosis.
- The viral envelope fuses with the vesicle membrane, releasing the nucleocapsids into the cytoplasm.
- The viral RNA from this enters the nucleus, where it is replicated to form mRNA using the viral RNA polymerase enzyme.