Models of viral <i>cis</i>-activities and HCV replicase structure and function.

<p>(<b>A</b>) Ribosome-induced change in RNA structure. (<b>B</b>) Nascent <i>cis</i>-acting polypeptide (orange) recruiting the viral RNA-ribosome complex to a site of replication via an interaction partner (yellow). (<b>C</b>) A <i>cis</i>-acting protein (orange) recruiting the viral RNA to site of replication. (<b>D</b>) NS5B <i>trans</i>-complementation via protein transfer. (<b>E</b>) NS5B <i>trans</i>-complementation via RNA transfer. (<b>F</b>) NS5B <i>trans</i>-complementation requires NS3–5B expression. (<b>G</b>) Translation of NS5B is required in <i>cis</i>. (<b>H</b>) Potential NS3-NS4A interactions of the 3m6 and 4Am1 mutants. NS3-4A can form homodimers where each monomer contributes either NS3 or NS4A (left); alternatively, NS3-NS4A may dissociate and reassociate to form separate active and inactive monomers (right).