In situ studies of Hepatitis C virus replication complexes using cryo-electron tomography

• Applicant: Benjamin Götte, Ph.D.
• Subject Area: Structural Biology ; Virology
• Term: from 2021 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 455590986

Single-stranded positive-sense RNA (ss(+)RNA) viruses extensively remodel host cell membranes to establish membranous replication complexes, which provide a protective environment for viral RNA replication. A key component of replication complexes is the viral membrane-associated replicase. The replicase is often comprised of multiple viral proteins, which act cooperatively to catalyze RNA replication and provide additional non-enzymatic, presumably architectural, functions. Whereas structures and activities of individual replicase proteins have been thoroughly studied in vitro, their assemblies and complex interplay required for biogenesis of replication complexes and RNA replication activity within cells remain poorly understood. Cryogenic electron tomography (cryo-ET) has experienced major technical advances within recent years. In combination with improved image processing, cryo-ET allows visualization of membrane-associated macromolecular assemblies within cells and at nanometer to sub-nanometer resolution. We aim to use cryo-ET to investigate structural characteristics of Hepatitis C virus (HCV) replication complexes in situ. HCV replication complexes share morphological and functional characteristics with replication complexes of other important pathogenic ss(+)RNA viruses, including coronaviruses and poliovirus, which suggests similarities in structural composition. Revealing the higher-order structures of replicase proteins in complex with the viral RNA in situ is required to provide a mechanistic understanding for replication complex formation and replicase function.

• DFG Programme: WBP Fellowship
• International Connection: USA
• Host: Professorin Anna Marie Pyle, Ph.D.