Mapping mutational effects along the evolutionary landscape of HIV envelope
- Fred Hutchinson Cancer Research Center, United States
Abstract
The immediate evolutionary space accessible to HIV is largely determined by how single amino-acid mutations affect fitness. These mutational effects can shift as the virus evolves. However, the prevalence of such shifts in mutational effects remains unclear. Here we quantify the effects on viral growth of all amino-acid mutations to two HIV envelope (Env) proteins that differ at >100 residues. Most mutations similarly affect both Envs, but the amino-acid preferences of a minority of sites have clearly shifted. These shifted sites usually prefer a specific amino acid in one Env, but tolerate many amino acids in the other. Surprisingly, shifts are only slightly enriched at sites that have substituted between the Envs-and many occur at residues that do not even contact substitutions. Therefore, long-range epistasis can unpredictably shift Env's mutational tolerance during HIV evolution, although the amino-acid preferences of most sites are conserved between moderately diverged viral strains.
Data availability
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Deep mutational scanning of BF520Publicly available at the NCBI SAMN06313000.
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Deep mutational scanning of BG505Publicly available at the NCBI SAMN07718028.
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Computer codehttps://github.com/jbloomlab/EnvMutationalShiftsPaper.
Article and author information
Author details
Funding
National Institutes of Health (R01-AI127893)
- Jesse D Bloom
National Science Foundation (DGE-1256082)
- Adam S Dingens
Howard Hughes Medical Institute (Faculty Scholar Grant)
- Jesse D Bloom
Simons Foundation (Faculty Scholar Grant)
- Jesse D Bloom
Collaboration for AIDS Vaccine Discovery (OPP1111923)
- Jesse D Bloom
National Institutes of Health (DP1-DA039543)
- Julie Overbaugh
National Institutes of Health (T32GM007270)
- Hugh K Haddox
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Haddox et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Mapping mutational effects along the evolutionary landscape of HIV envelope
eLife 7:e34420.
https://doi.org/10.7554/eLife.34420
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