Related Experiment Video
Updated: Jun 23, 2025

A Miniaturized Glycan Microarray Assay for Assessing Avidity and Specificity of Influenza A Virus Hemagglutinins
Published on: May 29, 2016
Epistasis mediates the evolution of the receptor binding mode in recent human H3N2 hemagglutinin
Ruipeng Lei1, Weiwen Liang2, Wenhao O Ouyang1
1Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA.
Abstract:
The receptor-binding site of influenza A virus hemagglutinin partially overlaps with major antigenic sites and constantly evolves. In this study, we observe that mutations G186D and D190N in the hemagglutinin receptor-binding site have coevolved in two recent human H3N2 clades. X-ray crystallography results show that these mutations coordinately drive the evolution of the hemagglutinin receptor binding mode. Epistasis between G186D and D190N is further demonstrated by glycan binding and thermostability analyses. Immunization and neutralization experiments using mouse and human samples indicate that the evolution of receptor binding mode is accompanied by a change in antigenicity. Besides, combinatorial mutagenesis reveals that G186D and D190N, along with other natural mutations in recent H3N2 strains, alter the compatibility with a common egg-adaptive mutation in seasonal influenza vaccines. Overall, our findings elucidate the role of epistasis in shaping the recent evolution of human H3N2 hemagglutinin and substantiate the high evolvability of its receptor-binding mode.
Related Concept Videos
Exon Recombination
Exon shuffling follows “splice frame rules.” Each exon...
Viral Mutations
Conserved Binding Sites
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally...
Epistasis Analysis
Leaky Scanning
Epistasis

