Cryo-EM structures of CCHFV polymerase reveal a stepwise initiation stabilization pathway and a dual-site inhibition mechanism.

Cryo-EM structures reveal a stepwise stabilization pathway and dual-site inhibition mechanism of the CCHFV polymerase, offering new insights into viral replication control.

• Why it matters: Understanding the structural mechanisms of CCHFV polymerase is crucial because the virus causes severe disease with no approved treatments, and targeting its replication machinery could enable therapeutic development.
• What they did: High-resolution cryo-EM structures of the CCHFV L protein were determined in multiple states, including apo, RNA-bound, and inhibitor-bound forms, highlighting conserved motifs and RNA recognition sites.
• The result: The study uncovers how suramin inhibits the polymerase by blocking RNA binding and restricting conformational flexibility, paving the way for targeted antiviral strategies.