Efficient Estimates of Surface Diffusion Parameters for Spatio-Temporally Resolved Virus Replication Dynamics

Area of Science:

• Biophysics
• Virology
• Cell Biology

Background:

• Advanced treatments for viral diseases require understanding virus-host interactions.
• Hepatitis C virus (HCV) nonstructural proteins (NSPs), like NS5A, are crucial for replication and anchor to the endoplasmic reticulum (ER).
• Previous studies used fluorescence recovery after photobleaching (FRAP) and surface partial differential equations (sufPDEs) to analyze NSP diffusion.

Purpose of the Study:

• To develop a simplified scaling analysis for estimating the diffusion coefficient of NSPs on the ER membrane.
• To validate this new analytical method against numerical solutions and experimental data.

Main Methods:

• Scaling analysis of sufPDEs governing NSP diffusion on the ER.
• Numerical simulations of sufPDEs on flat and 3D ER geometries.
• Comparison of scaling analysis estimates with numerical solutions and experimental FRAP data.

Main Results:

• A novel method estimates the diffusion coefficient based on the ratio of membrane surface area to contour length in the FRAP region.
• The scaling analysis provides estimates comparable to those derived from extensive numerical simulations.
• The approach was successfully applied to existing experimental FRAP time-series data.

Conclusions:

• The developed scaling analysis offers a more efficient method for determining NSP diffusion coefficients.
• This biophysical insight into NSP dynamics on the ER can inform the development of novel antiviral strategies.
• The simplified approach enhances the analysis of viral replication mechanisms and aids in pandemic preparedness.