Phospholipid-driven conformational switching of HCV NS5A links protein folding to replication membrane remodeling
Phospholipids are essential for RNA virus replication, yet their role in modulating conformational dynamics of membrane-associated viral proteins remains poorly understood. For NS5A, a key replication factor of hepatitis C virus, previous crystallographic models fail to capture the lipid-driven conformational mechanics we uncover here. Using structural informatics and biochemical probing of pharmacophore-guided mutants in defined lipid environments, we evaluated competing NS5A domain 1 dimerization models. Our data reveal an alternative membrane-specific fold stabilized by polyproline hinges and phospholipids (PIPs) such as phosphatidylinositol-4-phosphate, a host lipid enriched at replication membranes. PIP binding promotes a conformational switch that drives dimerization, linking lipid sensing to membrane remodeling and host factor recruitment. This reciprocal mechanism-where a lipid allosterically modulates a viral protein that reshapes membranes-is blocked by the antiviral pibrentasvir. These findings define a lipid-driven structural switch that governs NS5A pleiotropy and highlight dynamic lipid-protein interfaces as targets for antiviral intervention.
Authors
- Christian Grimm (ORCID: https://orcid.org/0000-0001-9318-4352)
- Ricardo M. Biondi (ORCID: https://orcid.org/0000-0002-8873-7167)
- Robert Tampé (ORCID: https://orcid.org/0000-0002-0403-2160)
- Christoph Welsch (ORCID: https://orcid.org/0000-0002-1823-4863)
- D. J. Wood
- Richard A. Stanton (ORCID: https://orcid.org/0000-0003-4810-7002)
- Facundo Galceran (ORCID: https://orcid.org/0000-0001-5023-0582)
- Mikhail Kudryashev (ORCID: https://orcid.org/0000-0003-3550-6274)
- Bianca Introini (ORCID: https://orcid.org/0000-0001-8727-1070)
- Yasaman Karami (ORCID: https://orcid.org/0000-0001-8413-2665)
- Claudia Stroß
- MinKyung Yi (ORCID: https://orcid.org/0000-0002-5978-2452)
- Anna V. Bulankina
- R. Richter (ORCID: https://orcid.org/0000-0002-3831-7666)
- James H. Nettles
- Nico Kraus (ORCID: https://orcid.org/0000-0002-5162-1048)
- Rupert Abele (ORCID: https://orcid.org/0000-0001-6899-293X)
- Cristina Ortíz (ORCID: https://orcid.org/0000-0002-9049-5785)
- Hanaa Charif
- Mia König
- Jonas Hermann
- Daisuke Yamane
- Bernard Maigret
- Stefan Zeuzem
- Raymond F. Schinazi
Institutions
- Goethe University Frankfurt (DE)
- Centre National de la Recherche Scientifique (FR)
- Emory University (US)
- Savannah State University (US)
- Max Delbrück Center (DE)
- Universidad de Buenos Aires (AR)
- Tokyo Metropolitan Institute of Medical Science (JP)
- Laboratoire Lorrain de Recherche en Informatique et ses Applications (FR)
- Max Planck Institute of Biophysics (DE)
- University Hospital Frankfurt (DE)
- Children's Healthcare of Atlanta (US)
- Instituto de Neurología de Buenos Aires (AR)
- Institute of Molecular Biology (DE)
- Fundación Ciencias Exactas y Naturales (AR)
- The University of Texas Medical Branch at Galveston (US)
- Charité - Universitätsmedizin Berlin (DE)
Publication Details
- Journal
- Science Advances
- Published
- 2026-04-03
- DOI
- https://doi.org/10.1126/sciadv.aeb8863
- Citations
- 2
- Primary Topic
- Hepatitis C virus research
- Type
- article
- Field-Weighted Citation Impact
- 30.20
Funders
- Alexander von Humboldt-Stiftung
- Gilead Sciences
- Deutsche Forschungsgemeinschaft
- Else Kröner-Fresenius-Stiftung
- Dr. Rolf M. Schwiete Stiftung
- National Institutes of Health
- European Research Council
- Japan Society for the Promotion of Science