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bioRxiv · 10.1101/047571

Accurate measurement of the effects of all amino-acid mutations to influenza hemagglutinin

Michael B Doud·Jesse D Bloom
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Abstract

Influenza genes evolve mostly via point mutations, and so knowing the effect of every amino-acid mutation provides information about evolutionary paths available to the virus. We previously used high-throughput mutagenesis and deep sequencing to estimate the effects of all mutations to an H1 influenza hemagglutinin on viral replication in cell culture (Thyagarajan and Bloom, 2014); however, these measurements suffered from sub-stantial noise. Here we describe advances that greatly improve the accuracy and reproducibility of our measurements. The largest improvements come from using a helper virus to reduce bottlenecks when generating viruses from plasmids. Our measurements confirm that antigenic sites on the globular head of hemagglutinin are highly tolerant of mutations. However, other regions - including stalk epitopes targeted by broadly neutralizing antibodies - have a limited capacity to evolve. The ability to accurately measure the effects of all influenza mutations should enhance efforts to understand and predict viral evolution.

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Michael B Doud, Jesse D Bloom. 2016-04-07. Accurate measurement of the effects of all amino-acid mutations to influenza hemagglutinin. https://doi.org/10.1101/047571

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