Energy landscape reshaped by strain-specific mutations underlies epistasis in NS1 evolution of influenza A virus.
Kim, I., Dubrow, A., Zuniga, B., Zhao, B., Sherer, N., Bastiray, A., Li, P., Cho, J.H.(2022) Nat Commun 13: 5775-5775
- PubMed: 36182933
- DOI: https://doi.org/10.1038/s41467-022-33554-9
- Primary Citation of Related Structures:
7RCH - PubMed Abstract:
Elucidating how individual mutations affect the protein energy landscape is crucial for understanding how proteins evolve. However, predicting mutational effects remains challenging because of epistasis-the nonadditive interactions between mutations. Here, we investigate the biophysical mechanism of strain-specific epistasis in the nonstructural protein 1 (NS1) of influenza A viruses (IAVs). We integrate structural, kinetic, thermodynamic, and conformational dynamics analyses of four NS1s of influenza strains that emerged between 1918 and 2004. Although functionally near-neutral, strain-specific NS1 mutations exhibit long-range epistatic interactions with residues at the p85β-binding interface. We reveal that strain-specific mutations reshaped the NS1 energy landscape during evolution. Using NMR spin dynamics, we find that the strain-specific mutations altered the conformational dynamics of the hidden network of tightly packed residues, underlying the evolution of long-range epistasis. This work shows how near-neutral mutations silently alter the biophysical energy landscapes, resulting in diverse background effects during molecular evolution.
Organizational Affiliation:
Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA.