Structure of vesicular stomatitis virus L-P-N(0) complex by cyro-electron microscopy.

A cryo-electron microscopy structure of the vesicular stomatitis virus L–P–N0 polymerase complex shows N0 anchored by P at the RNA-product exit channel in a continuum of conformations.

• Why it matters: L coordinates transcription and replication, but how L’s carboxyl-terminal domain and P recruit N0 for encapsidation during genome replication was unclear.
• What they did: The authors determined the cryo-EM structure of a vesicular stomatitis virus polymerase complex comprising L–P and N0, with P directly engaging L’s carboxyl-terminal domain (LCTD).
• The result: The structure reveals a role for LCTD in encapsidation of nascent RNAs and provides the polymerase complex architecture required for genomic RNA replication.