1
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Zheng W. Predicting hotspots for disease-causing single nucleotide variants using sequences-based coevolution, network analysis, and machine learning. PLoS One 2024; 19:e0302504. [PMID: 38743747 PMCID: PMC11093321 DOI: 10.1371/journal.pone.0302504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 04/05/2024] [Indexed: 05/16/2024] Open
Abstract
To enable personalized medicine, it is important yet highly challenging to accurately predict disease-causing mutations in target proteins at high throughput. Previous computational methods have been developed using evolutionary information in combination with various biochemical and structural features of protein residues to discriminate neutral vs. deleterious mutations. However, the power of these methods is often limited because they either assume known protein structures or treat residues independently without fully considering their interactions. To address the above limitations, we build upon recent progress in machine learning, network analysis, and protein language models, and develop a sequences-based variant site prediction workflow based on the protein residue contact networks: 1. We employ and integrate various methods of building protein residue networks using state-of-the-art coevolution analysis tools (RaptorX, DeepMetaPSICOV, and SPOT-Contact) powered by deep learning. 2. We use machine learning algorithms (Random Forest, Gradient Boosting, and Extreme Gradient Boosting) to optimally combine 20 network centrality scores to jointly predict key residues as hot spots for disease mutations. 3. Using a dataset of 107 proteins rich in disease mutations, we rigorously evaluate the network scores individually and collectively (via machine learning). This work supports a promising strategy of combining an ensemble of network scores based on different coevolution analysis methods (and optionally predictive scores from other methods) via machine learning to predict hotspot sites of disease mutations, which will inform downstream applications of disease diagnosis and targeted drug design.
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Affiliation(s)
- Wenjun Zheng
- Department of Physics, State University of New York at Buffalo, Buffalo, NY, United States of America
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2
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Ose NJ, Campitelli P, Modi T, Kazan IC, Kumar S, Ozkan SB. Some mechanistic underpinnings of molecular adaptations of SARS-COV-2 spike protein by integrating candidate adaptive polymorphisms with protein dynamics. eLife 2024; 12:RP92063. [PMID: 38713502 PMCID: PMC11076047 DOI: 10.7554/elife.92063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024] Open
Abstract
We integrate evolutionary predictions based on the neutral theory of molecular evolution with protein dynamics to generate mechanistic insight into the molecular adaptations of the SARS-COV-2 spike (S) protein. With this approach, we first identified candidate adaptive polymorphisms (CAPs) of the SARS-CoV-2 S protein and assessed the impact of these CAPs through dynamics analysis. Not only have we found that CAPs frequently overlap with well-known functional sites, but also, using several different dynamics-based metrics, we reveal the critical allosteric interplay between SARS-CoV-2 CAPs and the S protein binding sites with the human ACE2 (hACE2) protein. CAPs interact far differently with the hACE2 binding site residues in the open conformation of the S protein compared to the closed form. In particular, the CAP sites control the dynamics of binding residues in the open state, suggesting an allosteric control of hACE2 binding. We also explored the characteristic mutations of different SARS-CoV-2 strains to find dynamic hallmarks and potential effects of future mutations. Our analyses reveal that Delta strain-specific variants have non-additive (i.e., epistatic) interactions with CAP sites, whereas the less pathogenic Omicron strains have mostly additive mutations. Finally, our dynamics-based analysis suggests that the novel mutations observed in the Omicron strain epistatically interact with the CAP sites to help escape antibody binding.
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Affiliation(s)
- Nicholas James Ose
- Department of Physics and Center for Biological Physics, Arizona State UniversityTempeUnited States
| | - Paul Campitelli
- Department of Physics and Center for Biological Physics, Arizona State UniversityTempeUnited States
| | - Tushar Modi
- Department of Physics and Center for Biological Physics, Arizona State UniversityTempeUnited States
| | - I Can Kazan
- Department of Physics and Center for Biological Physics, Arizona State UniversityTempeUnited States
| | - Sudhir Kumar
- Institute for Genomics and Evolutionary Medicine, Temple UniversityPhiladelphiaUnited States
- Department of Biology, Temple UniversityPhiladelphiaUnited States
- Center for Genomic Medicine Research, King Abdulaziz UniversityJeddahSaudi Arabia
| | - Sefika Banu Ozkan
- Department of Physics and Center for Biological Physics, Arizona State UniversityTempeUnited States
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3
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Biswas A, Choudhuri I, Arnold E, Lyumkis D, Haldane A, Levy RM. Kinetic coevolutionary models predict the temporal emergence of HIV-1 resistance mutations under drug selection pressure. Proc Natl Acad Sci U S A 2024; 121:e2316662121. [PMID: 38557187 PMCID: PMC11009627 DOI: 10.1073/pnas.2316662121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 02/23/2024] [Indexed: 04/04/2024] Open
Abstract
Drug resistance in HIV type 1 (HIV-1) is a pervasive problem that affects the lives of millions of people worldwide. Although records of drug-resistant mutations (DRMs) have been extensively tabulated within public repositories, our understanding of the evolutionary kinetics of DRMs and how they evolve together remains limited. Epistasis, the interaction between a DRM and other residues in HIV-1 protein sequences, is key to the temporal evolution of drug resistance. We use a Potts sequence-covariation statistical-energy model of HIV-1 protein fitness under drug selection pressure, which captures epistatic interactions between all positions, combined with kinetic Monte-Carlo simulations of sequence evolutionary trajectories, to explore the acquisition of DRMs as they arise in an ensemble of drug-naive patient protein sequences. We follow the time course of 52 DRMs in the enzymes protease, RT, and integrase, the primary targets of antiretroviral therapy. The rates at which DRMs emerge are highly correlated with their observed acquisition rates reported in the literature when drug pressure is applied. This result highlights the central role of epistasis in determining the kinetics governing DRM emergence. Whereas rapidly acquired DRMs begin to accumulate as soon as drug pressure is applied, slowly acquired DRMs are contingent on accessory mutations that appear only after prolonged drug pressure. We provide a foundation for using computational methods to determine the temporal evolution of drug resistance using Potts statistical potentials, which can be used to gain mechanistic insights into drug resistance pathways in HIV-1 and other infectious agents.
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Affiliation(s)
- Avik Biswas
- Center for Biophysics and Computational Biology, College of Science and Technology, Temple University, Philadelphia, PA19122
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA92037
- Department of Physics, University of California San Diego, La Jolla, CA92093
| | - Indrani Choudhuri
- Center for Biophysics and Computational Biology, College of Science and Technology, Temple University, Philadelphia, PA19122
- Department of Chemistry, Temple University, Philadelphia, PA19122
| | - Eddy Arnold
- Department of Chemistry and Chemical Biology, Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ08854
| | - Dmitry Lyumkis
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA92037
- Graduate School of Biological Sciences, Department of Molecular Biology, University of California San Diego, La Jolla, CA92093
| | - Allan Haldane
- Center for Biophysics and Computational Biology, College of Science and Technology, Temple University, Philadelphia, PA19122
- Department of Physics, Temple University, Philadelphia, PA19122
| | - Ronald M. Levy
- Center for Biophysics and Computational Biology, College of Science and Technology, Temple University, Philadelphia, PA19122
- Department of Chemistry, Temple University, Philadelphia, PA19122
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4
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Mohebbi F, Zelikovsky A, Mangul S, Chowell G, Skums P. Early detection of emerging viral variants through analysis of community structure of coordinated substitution networks. Nat Commun 2024; 15:2838. [PMID: 38565543 PMCID: PMC10987511 DOI: 10.1038/s41467-024-47304-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 03/20/2024] [Indexed: 04/04/2024] Open
Abstract
The emergence of viral variants with altered phenotypes is a public health challenge underscoring the need for advanced evolutionary forecasting methods. Given extensive epistatic interactions within viral genomes and known viral evolutionary history, efficient genomic surveillance necessitates early detection of emerging viral haplotypes rather than commonly targeted single mutations. Haplotype inference, however, is a significantly more challenging problem precluding the use of traditional approaches. Here, using SARS-CoV-2 evolutionary dynamics as a case study, we show that emerging haplotypes with altered transmissibility can be linked to dense communities in coordinated substitution networks, which become discernible significantly earlier than the haplotypes become prevalent. From these insights, we develop a computational framework for inference of viral variants and validate it by successful early detection of known SARS-CoV-2 strains. Our methodology offers greater scalability than phylogenetic lineage tracing and can be applied to any rapidly evolving pathogen with adequate genomic surveillance data.
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Affiliation(s)
- Fatemeh Mohebbi
- Department of Computer Science, Georgia State University, Atlanta, GA, USA
- Titus Family Department of Clinical Pharmacy, USC Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
| | - Alex Zelikovsky
- Department of Computer Science, Georgia State University, Atlanta, GA, USA
| | - Serghei Mangul
- Titus Family Department of Clinical Pharmacy, USC Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
- Department of Quantitative and Computational Biology, USC Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA, USA
| | - Gerardo Chowell
- School of Public Health, Georgia State University, Atlanta, GA, USA
| | - Pavel Skums
- Department of Computer Science, Georgia State University, Atlanta, GA, USA.
- School of Computing, College of Engineering, University of Connecticut, Storrs, CT, USA.
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5
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Schug A. Residue coevolution and mutational landscape for OmpR and NarL: You can teach old dogs new tricks. Biophys J 2024; 123:653-654. [PMID: 38379283 PMCID: PMC10995386 DOI: 10.1016/j.bpj.2024.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Revised: 02/19/2024] [Accepted: 02/19/2024] [Indexed: 02/22/2024] Open
Affiliation(s)
- Alexander Schug
- Jülich Supercomputing Centre, Forschungszentrum Jülich, Jülich, Germany; Faculty of Biology, University of Duisburg-Essen, Essen, Germany.
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6
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Chan CWF, Wang B, Nan L, Huang X, Mao T, Chu HY, Luo C, Chu H, Choi GCG, Shum HC, Wong ASL. High-throughput screening of genetic and cellular drivers of syncytium formation induced by the spike protein of SARS-CoV-2. Nat Biomed Eng 2024; 8:291-309. [PMID: 37996617 DOI: 10.1038/s41551-023-01140-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 10/18/2023] [Indexed: 11/25/2023]
Abstract
Mapping mutations and discovering cellular determinants that cause the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to induce infected cells to form syncytia would facilitate the development of strategies for blocking the formation of such cell-cell fusion. Here we describe high-throughput screening methods based on droplet microfluidics and the size-exclusion selection of syncytia, coupled with large-scale mutagenesis and genome-wide knockout screening via clustered regularly interspaced short palindromic repeats (CRISPR), for the large-scale identification of determinants of cell-cell fusion. We used the methods to perform deep mutational scans in spike-presenting cells to pinpoint mutable syncytium-enhancing substitutions in two regions of the spike protein (the fusion peptide proximal region and the furin-cleavage site). We also used a genome-wide CRISPR screen in cells expressing the receptor angiotensin-converting enzyme 2 to identify inhibitors of clathrin-mediated endocytosis that impede syncytium formation, which we validated in hamsters infected with SARS-CoV-2. Finding genetic and cellular determinants of the formation of syncytia may reveal insights into the physiological and pathological consequences of cell-cell fusion.
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Affiliation(s)
- Charles W F Chan
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Bei Wang
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Lang Nan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Xiner Huang
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Tianjiao Mao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Hoi Yee Chu
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Cuiting Luo
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Hin Chu
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Virology, Vaccinology and Therapeutics, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
- Department of Infectious Disease and Microbiology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, People's Republic of China.
| | - Gigi C G Choi
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
| | - Alan S L Wong
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
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7
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Alvarez S, Nartey CM, Mercado N, de la Paz JA, Huseinbegovic T, Morcos F. In vivo functional phenotypes from a computational epistatic model of evolution. Proc Natl Acad Sci U S A 2024; 121:e2308895121. [PMID: 38285950 PMCID: PMC10861889 DOI: 10.1073/pnas.2308895121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 12/19/2023] [Indexed: 01/31/2024] Open
Abstract
Computational models of evolution are valuable for understanding the dynamics of sequence variation, to infer phylogenetic relationships or potential evolutionary pathways and for biomedical and industrial applications. Despite these benefits, few have validated their propensities to generate outputs with in vivo functionality, which would enhance their value as accurate and interpretable evolutionary algorithms. We demonstrate the power of epistasis inferred from natural protein families to evolve sequence variants in an algorithm we developed called sequence evolution with epistatic contributions (SEEC). Utilizing the Hamiltonian of the joint probability of sequences in the family as fitness metric, we sampled and experimentally tested for in vivo [Formula: see text]-lactamase activity in Escherichia coli TEM-1 variants. These evolved proteins can have dozens of mutations dispersed across the structure while preserving sites essential for both catalysis and interactions. Remarkably, these variants retain family-like functionality while being more active than their wild-type predecessor. We found that depending on the inference method used to generate the epistatic constraints, different parameters simulate diverse selection strengths. Under weaker selection, local Hamiltonian fluctuations reliably predict relative changes to variant fitness, recapitulating neutral evolution. SEEC has the potential to explore the dynamics of neofunctionalization, characterize viral fitness landscapes, and facilitate vaccine development.
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Affiliation(s)
- Sophia Alvarez
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX75080
| | - Charisse M. Nartey
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX75080
| | - Nicholas Mercado
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX75080
| | | | - Tea Huseinbegovic
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX75080
| | - Faruck Morcos
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX75080
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX75080
- Center for Systems Biology, University of Texas at Dallas, Richardson, TX75080
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8
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Sesta L, Pagnani A, Fernandez-de-Cossio-Diaz J, Uguzzoni G. Inference of annealed protein fitness landscapes with AnnealDCA. PLoS Comput Biol 2024; 20:e1011812. [PMID: 38377054 PMCID: PMC10878520 DOI: 10.1371/journal.pcbi.1011812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 01/08/2024] [Indexed: 02/22/2024] Open
Abstract
The design of proteins with specific tasks is a major challenge in molecular biology with important diagnostic and therapeutic applications. High-throughput screening methods have been developed to systematically evaluate protein activity, but only a small fraction of possible protein variants can be tested using these techniques. Computational models that explore the sequence space in-silico to identify the fittest molecules for a given function are needed to overcome this limitation. In this article, we propose AnnealDCA, a machine-learning framework to learn the protein fitness landscape from sequencing data derived from a broad range of experiments that use selection and sequencing to quantify protein activity. We demonstrate the effectiveness of our method by applying it to antibody Rep-Seq data of immunized mice and screening experiments, assessing the quality of the fitness landscape reconstructions. Our method can be applied to several experimental cases where a population of protein variants undergoes various rounds of selection and sequencing, without relying on the computation of variants enrichment ratios, and thus can be used even in cases of disjoint sequence samples.
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Affiliation(s)
- Luca Sesta
- Department of Applied Science and Technology, Politecnico di Torino, Torino, Italy
| | - Andrea Pagnani
- Department of Applied Science and Technology, Politecnico di Torino, Torino, Italy
- Italian Institute for Genomic Medicine, Torino, Italy
- INFN, Sezione di Torino, Torino, Italy
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9
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Ose NJ, Campitelli P, Modi T, Can Kazan I, Kumar S, Banu Ozkan S. Some mechanistic underpinnings of molecular adaptations of SARS-COV-2 spike protein by integrating candidate adaptive polymorphisms with protein dynamics. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.14.557827. [PMID: 37745560 PMCID: PMC10515954 DOI: 10.1101/2023.09.14.557827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
We integrate evolutionary predictions based on the neutral theory of molecular evolution with protein dynamics to generate mechanistic insight into the molecular adaptations of the SARS-COV-2 Spike (S) protein. With this approach, we first identified Candidate Adaptive Polymorphisms (CAPs) of the SARS-CoV-2 Spike protein and assessed the impact of these CAPs through dynamics analysis. Not only have we found that CAPs frequently overlap with well-known functional sites, but also, using several different dynamics-based metrics, we reveal the critical allosteric interplay between SARS-CoV-2 CAPs and the S protein binding sites with the human ACE2 (hACE2) protein. CAPs interact far differently with the hACE2 binding site residues in the open conformation of the S protein compared to the closed form. In particular, the CAP sites control the dynamics of binding residues in the open state, suggesting an allosteric control of hACE2 binding. We also explored the characteristic mutations of different SARS-CoV-2 strains to find dynamic hallmarks and potential effects of future mutations. Our analyses reveal that Delta strain-specific variants have non-additive (i.e., epistatic) interactions with CAP sites, whereas the less pathogenic Omicron strains have mostly additive mutations. Finally, our dynamics-based analysis suggests that the novel mutations observed in the Omicron strain epistatically interact with the CAP sites to help escape antibody binding.
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Affiliation(s)
- Nicholas J. Ose
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, Arizona, United States of America
| | - Paul Campitelli
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, Arizona, United States of America
| | - Tushar Modi
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, Arizona, United States of America
| | - I. Can Kazan
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, Arizona, United States of America
| | - Sudhir Kumar
- Institute for Genomics and Evolutionary Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
- Department of Biology, Temple University, Philadelphia, Pennsylvania, United States of America
- Center for Genomic Medicine Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - S. Banu Ozkan
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, Arizona, United States of America
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10
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Bravi B. Development and use of machine learning algorithms in vaccine target selection. NPJ Vaccines 2024; 9:15. [PMID: 38242890 PMCID: PMC10798987 DOI: 10.1038/s41541-023-00795-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 12/07/2023] [Indexed: 01/21/2024] Open
Abstract
Computer-aided discovery of vaccine targets has become a cornerstone of rational vaccine design. In this article, I discuss how Machine Learning (ML) can inform and guide key computational steps in rational vaccine design concerned with the identification of B and T cell epitopes and correlates of protection. I provide examples of ML models, as well as types of data and predictions for which they are built. I argue that interpretable ML has the potential to improve the identification of immunogens also as a tool for scientific discovery, by helping elucidate the molecular processes underlying vaccine-induced immune responses. I outline the limitations and challenges in terms of data availability and method development that need to be addressed to bridge the gap between advances in ML predictions and their translational application to vaccine design.
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Affiliation(s)
- Barbara Bravi
- Department of Mathematics, Imperial College London, London, SW7 2AZ, UK.
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11
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Thadani NN, Gurev S, Notin P, Youssef N, Rollins NJ, Ritter D, Sander C, Gal Y, Marks DS. Learning from prepandemic data to forecast viral escape. Nature 2023; 622:818-825. [PMID: 37821700 PMCID: PMC10599991 DOI: 10.1038/s41586-023-06617-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 09/06/2023] [Indexed: 10/13/2023]
Abstract
Effective pandemic preparedness relies on anticipating viral mutations that are able to evade host immune responses to facilitate vaccine and therapeutic design. However, current strategies for viral evolution prediction are not available early in a pandemic-experimental approaches require host polyclonal antibodies to test against1-16, and existing computational methods draw heavily from current strain prevalence to make reliable predictions of variants of concern17-19. To address this, we developed EVEscape, a generalizable modular framework that combines fitness predictions from a deep learning model of historical sequences with biophysical and structural information. EVEscape quantifies the viral escape potential of mutations at scale and has the advantage of being applicable before surveillance sequencing, experimental scans or three-dimensional structures of antibody complexes are available. We demonstrate that EVEscape, trained on sequences available before 2020, is as accurate as high-throughput experimental scans at anticipating pandemic variation for SARS-CoV-2 and is generalizable to other viruses including influenza, HIV and understudied viruses with pandemic potential such as Lassa and Nipah. We provide continually revised escape scores for all current strains of SARS-CoV-2 and predict probable further mutations to forecast emerging strains as a tool for continuing vaccine development ( evescape.org ).
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Affiliation(s)
- Nicole N Thadani
- Marks Group, Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Sarah Gurev
- Marks Group, Department of Systems Biology, Harvard Medical School, Boston, MA, USA
- Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA, USA
| | - Pascal Notin
- OATML Group, Department of Computer Science, University of Oxford, Oxford, UK
| | - Noor Youssef
- Marks Group, Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Nathan J Rollins
- Marks Group, Department of Systems Biology, Harvard Medical School, Boston, MA, USA
- Seismic Therapeutic, Watertown, MA, USA
| | - Daniel Ritter
- Marks Group, Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Chris Sander
- Marks Group, Department of Systems Biology, Harvard Medical School, Boston, MA, USA
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Yarin Gal
- OATML Group, Department of Computer Science, University of Oxford, Oxford, UK
| | - Debora S Marks
- Marks Group, Department of Systems Biology, Harvard Medical School, Boston, MA, USA.
- Broad Institute of Harvard and MIT, Cambridge, MA, USA.
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12
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Bloom JD, Neher RA. Fitness effects of mutations to SARS-CoV-2 proteins. Virus Evol 2023; 9:vead055. [PMID: 37727875 PMCID: PMC10506532 DOI: 10.1093/ve/vead055] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/08/2023] [Accepted: 08/22/2023] [Indexed: 09/21/2023] Open
Abstract
Knowledge of the fitness effects of mutations to SARS-CoV-2 can inform assessment of new variants, design of therapeutics resistant to escape, and understanding of the functions of viral proteins. However, experimentally measuring effects of mutations is challenging: we lack tractable lab assays for many SARS-CoV-2 proteins, and comprehensive deep mutational scanning has been applied to only two SARS-CoV-2 proteins. Here, we develop an approach that leverages millions of publicly available SARS-CoV-2 sequences to estimate effects of mutations. We first calculate how many independent occurrences of each mutation are expected to be observed along the SARS-CoV-2 phylogeny in the absence of selection. We then compare these expected observations to the actual observations to estimate the effect of each mutation. These estimates correlate well with deep mutational scanning measurements. For most genes, synonymous mutations are nearly neutral, stop-codon mutations are deleterious, and amino acid mutations have a range of effects. However, some viral accessory proteins are under little to no selection. We provide interactive visualizations of effects of mutations to all SARS-CoV-2 proteins (https://jbloomlab.github.io/SARS2-mut-fitness/). The framework we describe is applicable to any virus for which the number of available sequences is sufficiently large that many independent occurrences of each neutral mutation are observed.
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Affiliation(s)
- Jesse D Bloom
- Basic Sciences and Computational Biology, Fred Hutchinson Cancer Center, 1100 Fairview Ave N, Seattle, WA 98109, USA
- Department of Genome Sciences, University of Washington, 3720 15th Ave NE, Seattle, WA 98195, USA
- Howard Hughes Medical Institute, 1100 Fairview Ave N, Seattle, WA 98109, USA
| | - Richard A Neher
- Biozentrum, University of Basel, Spitalstrasse 41, Basel 4056, Switzerland
- Swiss Institute of Bioinformatics, Lausanne 1015, Switzerl
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13
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Li X, Yan H, Wong G, Ouyang W, Cui J. Identifying featured indels associated with SARS-CoV-2 fitness. Microbiol Spectr 2023; 11:e0226923. [PMID: 37698427 PMCID: PMC10580940 DOI: 10.1128/spectrum.02269-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 07/14/2023] [Indexed: 09/13/2023] Open
Abstract
As an RNA virus, severe acute respiratory coronavirus 2 (SARS-CoV-2) is known for frequent substitution mutations, and substitutions in important genome regions are often associated with viral fitness. However, whether indel mutations are related to viral fitness is generally ignored. Here we developed a computational methodology to investigate indels linked to fitness occurring in over 9 million SARS-CoV-2 genomes. Remarkably, by analyzing 31,642,404 deletion records and 1,981,308 insertion records, our pipeline identified 26,765 deletion types and 21,054 insertion types and discovered 65 indel types with a significant association with Pango lineages. We proposed the concept of featured indels representing the population of specific Pango lineages and variants as substitution mutations and termed these 65 indels as featured indels. The selective pressure of all indel types is assessed using the Bayesian model to explore the importance of indels. Our results exhibited higher selective pressure of indels like substitution mutations, which are important for assessing viral fitness and consistent with previous studies in vitro. Evaluation of the growth rate of each viral lineage indicated that indels play key roles in SARS-CoV-2 evolution and deserve more attention as substitution mutations. IMPORTANCE The fitness of indels in pathogen genome evolution has rarely been studied. We developed a computational methodology to investigate the severe acute respiratory coronavirus 2 genomes and analyze over 33 million records of indels systematically, ultimately proposing the concept of featured indels that can represent specific Pango lineages and identifying 65 featured indels. Machine learning model based on Bayesian inference and viral lineage growth rate evaluation suggests that these featured indels exhibit selection pressure comparable to replacement mutations. In conclusion, indels are not negligible for evaluating viral fitness.
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Affiliation(s)
- Xiang Li
- CAS Key Laboratory of Molecular Virology & Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
- AI for Science, Shanghai Artificial Intelligence Laboratory, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hongliang Yan
- AI for Science, Shanghai Artificial Intelligence Laboratory, Shanghai, China
| | - Gary Wong
- CAS Key Laboratory of Molecular Virology & Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
| | - Wanli Ouyang
- AI for Science, Shanghai Artificial Intelligence Laboratory, Shanghai, China
| | - Jie Cui
- CAS Key Laboratory of Molecular Virology & Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
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14
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Manoussopoulos Y, Anastassopoulou C, Ioannidis JPA, Tsakris A. Paired associated SARS-CoV-2 spike variable positions: a network analysis approach to emerging variants. mSystems 2023; 8:e0044023. [PMID: 37432011 PMCID: PMC10469592 DOI: 10.1128/msystems.00440-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 06/01/2023] [Indexed: 07/12/2023] Open
Abstract
Amino acids in variable positions of proteins may be correlated, with potential structural and functional implications. Here, we apply exact tests of independence in R × C contingency tables to examine noise-free associations between variable positions of the SARS-CoV-2 spike protein, using as a paradigm sequences from Greece deposited in GISAID (N = 6,683/1,078 full length) for the period 29 February 2020 to 26 April 2021 that essentially covers the first three pandemic waves. We examine the fate and complexity of these associations by network analysis, using associated positions (exact P ≤ 0.001 and Average Product Correction ≥ 2) as links and the corresponding positions as nodes. We found a temporal linear increase of positional differences and a gradual expansion of the number of position associations over time, represented by a temporally evolving intricate web, resulting in a non-random complex network of 69 nodes and 252 links. Overconnected nodes corresponded to the most adapted variant positions in the population, suggesting a direct relation between network degree and position functional importance. Modular analysis revealed 25 k-cliques comprising 3 to 11 nodes. At different k-clique resolutions, one to four communities were formed, capturing epistatic associations of circulating variants (Alpha, Beta, B.1.1.318), but also Delta, which dominated the evolutionary landscape later in the pandemic. Cliques of aminoacidic positional associations tended to occur in single sequences, enabling the recognition of epistatic positions in real-world virus populations. Our findings provide a novel way of understanding epistatic relationships in viral proteins with potential applications in the design of virus control procedures. IMPORTANCE Paired positional associations of adapted amino acids in virus proteins may provide new insights for understanding virus evolution and variant formation. We investigated potential intramolecular relationships between variable SARS-CoV-2 spike positions by exact tests of independence in R × C contingency tables, having applied Average Product Correction (APC) to eliminate background noise. Associated positions (exact P ≤ 0.001 and APC ≥ 2) formed a non-random, epistatic network of 25 cliques and 1-4 communities at different clique resolutions, revealing evolutionary ties between variable positions of circulating variants and a predictive potential of previously unknown network positions. Cliques of different sizes represented theoretical combinations of changing residues in sequence space, allowing the identification of significant aminoacidic combinations in single sequences of real-world populations. Our analytic approach that links network structural aspects to mutational aminoacidic combinations in the spike sequence population offers a novel way to understand virus epidemiology and evolution.
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Affiliation(s)
- Yiannis Manoussopoulos
- Department of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
- ELGO-Demeter, Plant Protection Division of Patras, Laboratory of Virology, Patras, Greece
| | - Cleo Anastassopoulou
- Department of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - John P. A. Ioannidis
- Department of Medicine, Stanford University, Stanford, California, USA
- Departments of Epidemiology and Population Health, Stanford University, Stanford, California, USA
- Department of Biomedical Data Science, Stanford University, Stanford, California, USA
- Department of Statistics, Stanford University, Stanford, California, USA
| | - Athanasios Tsakris
- Department of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
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15
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Wang G, Liu X, Wang K, Gao Y, Li G, Baptista-Hon DT, Yang XH, Xue K, Tai WH, Jiang Z, Cheng L, Fok M, Lau JYN, Yang S, Lu L, Zhang P, Zhang K. Deep-learning-enabled protein-protein interaction analysis for prediction of SARS-CoV-2 infectivity and variant evolution. Nat Med 2023; 29:2007-2018. [PMID: 37524952 DOI: 10.1038/s41591-023-02483-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 06/28/2023] [Indexed: 08/02/2023]
Abstract
Host-pathogen interactions and pathogen evolution are underpinned by protein-protein interactions between viral and host proteins. An understanding of how viral variants affect protein-protein binding is important for predicting viral-host interactions, such as the emergence of new pathogenic SARS-CoV-2 variants. Here we propose an artificial intelligence-based framework called UniBind, in which proteins are represented as a graph at the residue and atom levels. UniBind integrates protein three-dimensional structure and binding affinity and is capable of multi-task learning for heterogeneous biological data integration. In systematic tests on benchmark datasets and further experimental validation, UniBind effectively and scalably predicted the effects of SARS-CoV-2 spike protein variants on their binding affinities to the human ACE2 receptor, as well as to SARS-CoV-2 neutralizing monoclonal antibodies. Furthermore, in a cross-species analysis, UniBind could be applied to predict host susceptibility to SARS-CoV-2 variants and to predict future viral variant evolutionary trends. This in silico approach has the potential to serve as an early warning system for problematic emerging SARS-CoV-2 variants, as well as to facilitate research on protein-protein interactions in general.
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Affiliation(s)
- Guangyu Wang
- State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing, China.
| | - Xiaohong Liu
- Instutite for Artificial Intelligence in Medicine and Faculty of Medicine, Macau University of Science and Technology, Macau, China
- UCL Cancer Institute, University College London, London, UK
| | - Kai Wang
- Department of Big Data and Biomedical Artificial Intelligence, National Biomedical Imaging Center, College of Future Technology, Peking University and Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Yuanxu Gao
- Guangzhou National Laboratory, Guangzhou, China
| | - Gen Li
- Guangzhou National Laboratory, Guangzhou, China
- Guangzhou Women and Children's Medical Center, Guangzhou, China
| | - Daniel T Baptista-Hon
- Instutite for Artificial Intelligence in Medicine and Faculty of Medicine, Macau University of Science and Technology, Macau, China
- Zhuhai International Eye Center and Provincial Key Laboratory of Tumor Interventional Diagnosis and Treatment, Zhuhai People's Hospital and the First Affiliated Hospital of Faculty of Medicine, Macau University of Science and Technology, Guangdong, China
| | - Xiaohong Helena Yang
- Instutite for Artificial Intelligence in Medicine and Faculty of Medicine, Macau University of Science and Technology, Macau, China
| | - Kanmin Xue
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Wa Hou Tai
- Instutite for Artificial Intelligence in Medicine and Faculty of Medicine, Macau University of Science and Technology, Macau, China
| | - Zeyu Jiang
- State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing, China
| | - Linling Cheng
- Instutite for Artificial Intelligence in Medicine and Faculty of Medicine, Macau University of Science and Technology, Macau, China
- Zhuhai International Eye Center and Provincial Key Laboratory of Tumor Interventional Diagnosis and Treatment, Zhuhai People's Hospital and the First Affiliated Hospital of Faculty of Medicine, Macau University of Science and Technology, Guangdong, China
| | - Manson Fok
- Instutite for Artificial Intelligence in Medicine and Faculty of Medicine, Macau University of Science and Technology, Macau, China
| | - Johnson Yiu-Nam Lau
- Departments of Biology and Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR, China
| | - Shengyong Yang
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Ligong Lu
- Instutite for Artificial Intelligence in Medicine and Faculty of Medicine, Macau University of Science and Technology, Macau, China
- Zhuhai International Eye Center and Provincial Key Laboratory of Tumor Interventional Diagnosis and Treatment, Zhuhai People's Hospital and the First Affiliated Hospital of Faculty of Medicine, Macau University of Science and Technology, Guangdong, China
| | - Ping Zhang
- State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing, China
| | - Kang Zhang
- Instutite for Artificial Intelligence in Medicine and Faculty of Medicine, Macau University of Science and Technology, Macau, China.
- Department of Big Data and Biomedical Artificial Intelligence, National Biomedical Imaging Center, College of Future Technology, Peking University and Peking-Tsinghua Center for Life Sciences, Beijing, China.
- Guangzhou National Laboratory, Guangzhou, China.
- Zhuhai International Eye Center and Provincial Key Laboratory of Tumor Interventional Diagnosis and Treatment, Zhuhai People's Hospital and the First Affiliated Hospital of Faculty of Medicine, Macau University of Science and Technology, Guangdong, China.
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16
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Jiao Y, Xing Y, Sun Y. Impact of E484Q and L452R Mutations on Structure and Binding Behavior of SARS-CoV-2 B.1.617.1 Using Deep Learning AlphaFold2, Molecular Docking and Dynamics Simulation. Int J Mol Sci 2023; 24:11564. [PMID: 37511322 PMCID: PMC10380202 DOI: 10.3390/ijms241411564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/04/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
During the outbreak of COVID-19, many SARS-CoV-2 variants presented key amino acid mutations that influenced their binding abilities with angiotensin-converting enzyme 2 (hACE2) and neutralizing antibodies. For the B.1.617 lineage, there had been fears that two key mutations, i.e., L452R and E484Q, would have additive effects on the evasion of neutralizing antibodies. In this paper, we systematically investigated the impact of the L452R and E484Q mutations on the structure and binding behavior of B.1.617.1 using deep learning AlphaFold2, molecular docking and dynamics simulation. We firstly predicted and verified the structure of the S protein containing L452R and E484Q mutations via the AlphaFold2-calculated pLDDT value and compared it with the experimental structure. Next, a molecular simulation was performed to reveal the structural and interaction stabilities of the S protein of the double mutant variant with hACE2. We found that the double mutations, L452R and E484Q, could lead to a decrease in hydrogen bonds and higher interaction energy between the S protein and hACE2, demonstrating the lower structural stability and the worse binding affinity in the long dynamic evolutional process, even though the molecular docking showed the lower binding energy score of the S1 RBD of the double mutant variant with hACE2 than that of the wild type (WT) with hACE2. In addition, docking to three approved neutralizing monoclonal antibodies (mAbs) showed a reduced binding affinity of the double mutant variant, suggesting a lower neutralization ability of the mAbs against the double mutant variant. Our study helps lay the foundation for further SARS-CoV-2 studies and provides bioinformatics and computational insights into how the double mutations lead to immune evasion, which could offer guidance for subsequent biomedical studies.
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Affiliation(s)
- Yanqi Jiao
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Yichen Xing
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Yao Sun
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
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17
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Rouzine IM, Rozhnova G. Evolutionary implications of SARS-CoV-2 vaccination for the future design of vaccination strategies. COMMUNICATIONS MEDICINE 2023; 3:86. [PMID: 37336956 DOI: 10.1038/s43856-023-00320-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 06/07/2023] [Indexed: 06/21/2023] Open
Abstract
Once the first SARS-CoV-2 vaccine became available, mass vaccination was the main pillar of the public health response to the COVID-19 pandemic. It was very effective in reducing hospitalizations and deaths. Here, we discuss the possibility that mass vaccination might accelerate SARS-CoV-2 evolution in antibody-binding regions compared to natural infection at the population level. Using the evidence of strong genetic variation in antibody-binding regions and taking advantage of the similarity between the envelope proteins of SARS-CoV-2 and influenza, we assume that immune selection pressure acting on these regions of the two viruses is similar. We discuss the consequences of this assumption for SARS-CoV-2 evolution in light of mathematical models developed previously for influenza. We further outline the implications of this phenomenon, if our assumptions are confirmed, for the future design of SARS-CoV-2 vaccination strategies.
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Affiliation(s)
- Igor M Rouzine
- Immunogenetics, Sechenov Institute of Evolutionary Physiology and Biochemistry of Russian Academy of Sciences, Saint-Petersburg, Russia.
| | - Ganna Rozhnova
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
- BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal.
- Center for Complex Systems Studies (CCSS), Utrecht University, Utrecht, The Netherlands.
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18
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Bloom JD, Neher RA. Fitness effects of mutations to SARS-CoV-2 proteins. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.30.526314. [PMID: 36778462 PMCID: PMC9915511 DOI: 10.1101/2023.01.30.526314] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Knowledge of the fitness effects of mutations to SARS-CoV-2 can inform assessment of new variants, design of therapeutics resistant to escape, and understanding of the functions of viral proteins. However, experimentally measuring effects of mutations is challenging: we lack tractable lab assays for many SARS-CoV-2 proteins, and comprehensive deep mutational scanning has been applied to only two SARS-CoV-2 proteins. Here we develop an approach that leverages millions of publicly available SARS-CoV-2 sequences to estimate effects of mutations. We first calculate how many independent occurrences of each mutation are expected to be observed along the SARS-CoV-2 phylogeny in the absence of selection. We then compare these expected observations to the actual observations to estimate the effect of each mutation. These estimates correlate well with deep mutational scanning measurements. For most genes, synonymous mutations are nearly neutral, stop-codon mutations are deleterious, and amino-acid mutations have a range of effects. However, some viral accessory proteins are under little to no selection. We provide interactive visualizations of effects of mutations to all SARS-CoV-2 proteins (https://jbloomlab.github.io/SARS2-mut-fitness/). The framework we describe is applicable to any virus for which the number of available sequences is sufficiently large that many independent occurrences of each neutral mutation are observed.
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Affiliation(s)
- Jesse D. Bloom
- Basic Sciences and Computational Biology, Fred Hutchinson Cancer Center
- Department of Genome Sciences, University of Washington
- Howard Hughes Medical Institute
| | - Richard A. Neher
- Biozentrum, University of Basel
- Swiss Institute of Bioinformatics
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19
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Alvarez S, Nartey CM, Mercado N, de la Paz A, Huseinbegovic T, Morcos F. In vivo functional phenotypes from a computational epistatic model of evolution. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.24.542176. [PMID: 37292895 PMCID: PMC10245989 DOI: 10.1101/2023.05.24.542176] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Computational models of evolution are valuable for understanding the dynamics of sequence variation, to infer phylogenetic relationships or potential evolutionary pathways and for biomedical and industrial applications. Despite these benefits, few have validated their propensities to generate outputs with in vivo functionality, which would enhance their value as accurate and interpretable evolutionary algorithms. We demonstrate the power of epistasis inferred from natural protein families to evolve sequence variants in an algorithm we developed called Sequence Evolution with Epistatic Contributions. Utilizing the Hamiltonian of the joint probability of sequences in the family as fitness metric, we sampled and experimentally tested for in vivo β -lactamase activity in E. coli TEM-1 variants. These evolved proteins can have dozens of mutations dispersed across the structure while preserving sites essential for both catalysis and interactions. Remarkably, these variants retain family-like functionality while being more active than their WT predecessor. We found that depending on the inference method used to generate the epistatic constraints, different parameters simulate diverse selection strengths. Under weaker selection, local Hamiltonian fluctuations reliably predict relative changes to variant fitness, recapitulating neutral evolution. SEEC has the potential to explore the dynamics of neofunctionalization, characterize viral fitness landscapes and facilitate vaccine development.
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Affiliation(s)
- Sophia Alvarez
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Charisse M. Nartey
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Nicholas Mercado
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Alberto de la Paz
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Tea Huseinbegovic
- School of Natural Sciences and Mathematics, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Faruck Morcos
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX 75080, USA
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
- Center for Systems Biology, University of Texas at Dallas, Richardson, TX 75080, USA
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20
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Verkhivker G, Alshahrani M, Gupta G. Balancing Functional Tradeoffs between Protein Stability and ACE2 Binding in the SARS-CoV-2 Omicron BA.2, BA.2.75 and XBB Lineages: Dynamics-Based Network Models Reveal Epistatic Effects Modulating Compensatory Dynamic and Energetic Changes. Viruses 2023; 15:1143. [PMID: 37243229 PMCID: PMC10221141 DOI: 10.3390/v15051143] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/27/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
Evolutionary and functional studies suggested that the emergence of the Omicron variants can be determined by multiple fitness trade-offs including the immune escape, binding affinity for ACE2, conformational plasticity, protein stability and allosteric modulation. In this study, we systematically characterize conformational dynamics, structural stability and binding affinities of the SARS-CoV-2 Spike Omicron complexes with the host receptor ACE2 for BA.2, BA.2.75, XBB.1 and XBB.1.5 variants. We combined multiscale molecular simulations and dynamic analysis of allosteric interactions together with the ensemble-based mutational scanning of the protein residues and network modeling of epistatic interactions. This multifaceted computational study characterized molecular mechanisms and identified energetic hotspots that can mediate the predicted increased stability and the enhanced binding affinity of the BA.2.75 and XBB.1.5 complexes. The results suggested a mechanism driven by the stability hotspots and a spatially localized group of the Omicron binding affinity centers, while allowing for functionally beneficial neutral Omicron mutations in other binding interface positions. A network-based community model for the analysis of epistatic contributions in the Omicron complexes is proposed revealing the key role of the binding hotspots R498 and Y501 in mediating community-based epistatic couplings with other Omicron sites and allowing for compensatory dynamics and binding energetic changes. The results also showed that mutations in the convergent evolutionary hotspot F486 can modulate not only local interactions but also rewire the global network of local communities in this region allowing the F486P mutation to restore both the stability and binding affinity of the XBB.1.5 variant which may explain the growth advantages over the XBB.1 variant. The results of this study are consistent with a broad range of functional studies rationalizing functional roles of the Omicron mutation sites that form a coordinated network of hotspots enabling a balance of multiple fitness tradeoffs and shaping up a complex functional landscape of virus transmissibility.
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Affiliation(s)
- Gennady Verkhivker
- Keck Center for Science and Engineering, Graduate Program in Computational and Data Sciences, Schmid College of Science and Technology, Chapman University, Orange, CA 92866, USA; (M.A.); (G.G.)
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA 92618, USA
| | - Mohammed Alshahrani
- Keck Center for Science and Engineering, Graduate Program in Computational and Data Sciences, Schmid College of Science and Technology, Chapman University, Orange, CA 92866, USA; (M.A.); (G.G.)
| | - Grace Gupta
- Keck Center for Science and Engineering, Graduate Program in Computational and Data Sciences, Schmid College of Science and Technology, Chapman University, Orange, CA 92866, USA; (M.A.); (G.G.)
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21
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Ziegler C, Martin J, Sinner C, Morcos F. Latent generative landscapes as maps of functional diversity in protein sequence space. Nat Commun 2023; 14:2222. [PMID: 37076519 PMCID: PMC10113739 DOI: 10.1038/s41467-023-37958-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 04/05/2023] [Indexed: 04/21/2023] Open
Abstract
Variational autoencoders are unsupervised learning models with generative capabilities, when applied to protein data, they classify sequences by phylogeny and generate de novo sequences which preserve statistical properties of protein composition. While previous studies focus on clustering and generative features, here, we evaluate the underlying latent manifold in which sequence information is embedded. To investigate properties of the latent manifold, we utilize direct coupling analysis and a Potts Hamiltonian model to construct a latent generative landscape. We showcase how this landscape captures phylogenetic groupings, functional and fitness properties of several systems including Globins, β-lactamases, ion channels, and transcription factors. We provide support on how the landscape helps us understand the effects of sequence variability observed in experimental data and provides insights on directed and natural protein evolution. We propose that combining generative properties and functional predictive power of variational autoencoders and coevolutionary analysis could be beneficial in applications for protein engineering and design.
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Affiliation(s)
- Cheyenne Ziegler
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Jonathan Martin
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Claude Sinner
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Faruck Morcos
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, 75080, USA.
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, 75080, USA.
- Center for Systems Biology, University of Texas at Dallas, Richardson, TX, 75080, USA.
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22
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Dichio V, Zeng HL, Aurell E. Statistical genetics in and out of quasi-linkage equilibrium. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2023; 86:052601. [PMID: 36944245 DOI: 10.1088/1361-6633/acc5fa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 03/21/2023] [Indexed: 06/18/2023]
Abstract
This review is about statistical genetics, an interdisciplinary topic between statistical physics and population biology. The focus is on the phase ofquasi-linkage equilibrium(QLE). Our goals here are to clarify under which conditions the QLE phase can be expected to hold in population biology and how the stability of the QLE phase is lost. The QLE state, which has many similarities to a thermal equilibrium state in statistical mechanics, was discovered by M Kimura for a two-locus two-allele model, and was extended and generalized to the global genome scale byNeher&Shraiman (2011). What we will refer to as the Kimura-Neher-Shraiman theory describes a population evolving due to the mutations, recombination, natural selection and possibly genetic drift. A QLE phase exists at sufficiently high recombination rate (r) and/or mutation ratesµwith respect to selection strength. We show how in QLE it is possible to infer the epistatic parameters of the fitness function from the knowledge of the (dynamical) distribution of genotypes in a population. We further consider the breakdown of the QLE regime for high enough selection strength. We review recent results for the selection-mutation and selection-recombination dynamics. Finally, we identify and characterize a new phase which we call the non-random coexistence where variability persists in the population without either fixating or disappearing.
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Affiliation(s)
- Vito Dichio
- Sorbonne Université, Paris Brain Institute-ICM, CNRS, Inria, Inserm, AP-HP, Hôpital de la Pitié Salpêtrière, F-75013 Paris, France
| | - Hong-Li Zeng
- School of Science, Nanjing University of Posts and Telecommunications, New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing 210023, People's Republic of China
| | - Erik Aurell
- Department of Computational Science and Technology, KTH-Royal Institute of Technology, AlbaNova University Center, SE-106 91 Stockholm, Sweden
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23
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State of the art in epitope mapping and opportunities in COVID-19. Future Sci OA 2023; 16:FSO832. [PMID: 36897962 PMCID: PMC9987558 DOI: 10.2144/fsoa-2022-0048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 02/15/2023] [Indexed: 03/08/2023] Open
Abstract
The understanding of any disease calls for studying specific biological structures called epitopes. One important tool recently drawing attention and proving efficiency in both diagnosis and vaccine development is epitope mapping. Several techniques have been developed with the urge to provide precise epitope mapping for use in designing sensitive diagnostic tools and developing rpitope-based vaccines (EBVs) as well as therapeutics. In this review, we will discuss the state of the art in epitope mapping with a special emphasis on accomplishments and opportunities in combating COVID-19. These comprise SARS-CoV-2 variant analysis versus the currently available immune-based diagnostic tools and vaccines, immunological profile-based patient stratification, and finally, exploring novel epitope targets for potential prophylactic, therapeutic or diagnostic agents for COVID-19.
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24
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Neverov AD, Fedonin G, Popova A, Bykova D, Bazykin G. Coordinated evolution at amino acid sites of SARS-CoV-2 spike. eLife 2023; 12:82516. [PMID: 36752391 PMCID: PMC9908078 DOI: 10.7554/elife.82516] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 01/15/2023] [Indexed: 02/05/2023] Open
Abstract
SARS-CoV-2 has adapted in a stepwise manner, with multiple beneficial mutations accumulating in a rapid succession at origins of VOCs, and the reasons for this are unclear. Here, we searched for coordinated evolution of amino acid sites in the spike protein of SARS-CoV-2. Specifically, we searched for concordantly evolving site pairs (CSPs) for which changes at one site were rapidly followed by changes at the other site in the same lineage. We detected 46 sites which formed 45 CSP. Sites in CSP were closer to each other in the protein structure than random pairs, indicating that concordant evolution has a functional basis. Notably, site pairs carrying lineage defining mutations of the four VOCs that circulated before May 2021 are enriched in CSPs. For the Alpha VOC, the enrichment is detected even if Alpha sequences are removed from analysis, indicating that VOC origin could have been facilitated by positive epistasis. Additionally, we detected nine discordantly evolving pairs of sites where mutations at one site unexpectedly rarely occurred on the background of a specific allele at another site, for example on the background of wild-type D at site 614 (four pairs) or derived Y at site 501 (three pairs). Our findings hint that positive epistasis between accumulating mutations could have delayed the assembly of advantageous combinations of mutations comprising at least some of the VOCs.
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Affiliation(s)
- Alexey Dmitrievich Neverov
- HSE UniversityMoscowRussian Federation,Central Research Institute for EpidemiologyMoscowRussian Federation
| | - Gennady Fedonin
- Central Research Institute for EpidemiologyMoscowRussian Federation,Moscow Institute of Physics and Technology (National Research University)MoscowRussian Federation,Institute for Information Transmission Problems (Kharkevich Institute) of the Russian Academy of SciencesMoscowRussian Federation
| | - Anfisa Popova
- Central Research Institute for EpidemiologyMoscowRussian Federation
| | - Daria Bykova
- Central Research Institute for EpidemiologyMoscowRussian Federation,Lomonosov Moscow State UniversityMoscowRussian Federation
| | - Georgii Bazykin
- Institute for Information Transmission Problems (Kharkevich Institute) of the Russian Academy of SciencesMoscowRussian Federation,Skolkovo Institute of Science and TechnologyMoscowRussian Federation
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25
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Bhadane R, Salo-Ahen OMH. High-Throughput Molecular Dynamics-Based Alchemical Free Energy Calculations for Predicting the Binding Free Energy Change Associated with the Selected Omicron Mutations in the Spike Receptor-Binding Domain of SARS-CoV-2. Biomedicines 2022; 10:2779. [PMID: 36359299 PMCID: PMC9687918 DOI: 10.3390/biomedicines10112779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 10/17/2022] [Accepted: 10/25/2022] [Indexed: 11/10/2023] Open
Abstract
The ongoing pandemic caused by SARS-CoV-2 has gone through various phases. Since the initial outbreak, the virus has mutated several times, with some lineages showing even stronger infectivity and faster spread than the original virus. Among all the variants, omicron is currently classified as a variant of concern (VOC) by the World Health Organization, as the previously circulating variants have been replaced by it. In this work, we have focused on the mutations observed in omicron sub lineages BA.1, BA.2, BA.4 and BA.5, particularly at the receptor-binding domain (RBD) of the spike protein that is responsible for the interactions with the host ACE2 receptor and binding of antibodies. Studying such mutations is particularly important for understanding the viral infectivity, spread of the disease and for tracking the escape routes of this virus from antibodies. Molecular dynamics (MD) based alchemical free energy calculations have been shown to be very accurate in predicting the free energy change, due to a mutation that could have a deleterious or a stabilizing effect on either the protein itself or its binding affinity to another protein. Here, we investigated the significance of five spike RBD mutations on the stability of the spike protein binding to ACE2 by free energy calculations using high throughput MD simulations. For comparison, we also used conventional MD simulations combined with a Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) based approach, and compared our results with the available experimental data. Overall, the alchemical free energy calculations performed far better than the MM-GBSA approach in predicting the individual impact of the mutations. When considering the experimental variation, the alchemical free energy method was able to produce a relatively accurate prediction for N501Y, the mutant that has previously been reported to increase the binding affinity to hACE2. On the other hand, the other individual mutations seem not to have a significant effect on the spike RBD binding affinity towards hACE2.
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Affiliation(s)
- Rajendra Bhadane
- Structural Bioinformatics Laboratory, Faculty of Science and Engineering, Biochemistry, Åbo Akademi University, FI-20520 Turku, Finland
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Pharmacy, Åbo Akademi University, FI-20520 Turku, Finland
| | - Outi M. H. Salo-Ahen
- Structural Bioinformatics Laboratory, Faculty of Science and Engineering, Biochemistry, Åbo Akademi University, FI-20520 Turku, Finland
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Pharmacy, Åbo Akademi University, FI-20520 Turku, Finland
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26
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Tubiana J, Xiang Y, Fan L, Wolfson HJ, Chen K, Schneidman-Duhovny D, Shi Y. Reduced B cell antigenicity of Omicron lowers host serologic response. Cell Rep 2022; 41:111512. [PMID: 36223774 PMCID: PMC9515332 DOI: 10.1016/j.celrep.2022.111512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 08/10/2022] [Accepted: 09/26/2022] [Indexed: 11/25/2022] Open
Abstract
The SARS-CoV-2 Omicron variant evades most neutralizing vaccine-induced antibodies and is associated with lower antibody titers upon breakthrough infections than previous variants. However, the mechanism remains unclear. Here, we find using a geometric deep-learning model that Omicron's extensively mutated receptor binding site (RBS) features reduced antigenicity compared with previous variants. Mice immunization experiments with different recombinant receptor binding domain (RBD) variants confirm that the serological response to Omicron is drastically attenuated and less potent. Analyses of serum cross-reactivity and competitive ELISA reveal a reduction in antibody response across both variable and conserved RBD epitopes. Computational modeling confirms that the RBS has a potential for further antigenicity reduction while retaining efficient receptor binding. Finally, we find a similar trend of antigenicity reduction over decades for hCoV229E, a common cold coronavirus. Thus, our study explains the reduced antibody titers associated with Omicron infection and reveals a possible trajectory of future viral evolution.
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Affiliation(s)
- Jérôme Tubiana
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv 6997801, Israel,School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 9190501, Israel
| | - Yufei Xiang
- Center for Protein Engineering and Therapeutics, Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Li Fan
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Haim J. Wolfson
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Kong Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA.
| | - Dina Schneidman-Duhovny
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 9190501, Israel.
| | - Yi Shi
- Center for Protein Engineering and Therapeutics, Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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27
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Zeng HL, Liu Y, Dichio V, Aurell E. Temporal epistasis inference from more than 3 500 000 SARS-CoV-2 genomic sequences. Phys Rev E 2022; 106:044409. [PMID: 36397507 DOI: 10.1103/physreve.106.044409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
We use direct coupling analysis (DCA) to determine epistatic interactions between loci of variability of the SARS-CoV-2 virus, segmenting genomes by month of sampling. We use full-length, high-quality genomes from the GISAID repository up to October 2021 for a total of over 3 500 000 genomes. We find that DCA terms are more stable over time than correlations but nevertheless change over time as mutations disappear from the global population or reach fixation. Correlations are enriched for phylogenetic effects, and in particularly statistical dependencies at short genomic distances, while DCA brings out links at longer genomic distance. We discuss the validity of a DCA analysis under these conditions in terms of a transient auasilinkage equilibrium state. We identify putative epistatic interaction mutations involving loci in spike.
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Affiliation(s)
- Hong-Li Zeng
- School of Science, Nanjing University of Posts and Telecommunications, New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing 210023, China
| | - Yue Liu
- School of Science, Nanjing University of Posts and Telecommunications, New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing 210023, China
| | - Vito Dichio
- Inria Paris, Aramis Project Team, Paris 75013, France
- Institut du Cerveau, ICM, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, Paris, France
| | - Erik Aurell
- Department of Computational Science and Technology, AlbaNova University Center, SE-106 91 Stockholm, Sweden
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28
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Alemrajabi M, Macias Calix K, Assis R. Epistasis-Driven Evolution of the SARS-CoV-2 Secondary Structure. J Mol Evol 2022; 90:429-437. [PMID: 36178491 PMCID: PMC9523185 DOI: 10.1007/s00239-022-10073-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 09/02/2022] [Indexed: 11/25/2022]
Abstract
Epistasis is an evolutionary phenomenon whereby the fitness effect of a mutation depends on the genetic background in which it arises. A key source of epistasis in an RNA molecule is its secondary structure, which contains functionally important topological motifs held together by hydrogen bonds between Watson–Crick (WC) base pairs. Here we study epistasis in the secondary structure of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by examining properties of derived alleles arising from substitution mutations at ancestral WC base-paired and unpaired (UP) sites in 15 conserved topological motifs across the genome. We uncover fewer derived alleles and lower derived allele frequencies at WC than at UP sites, supporting the hypothesis that modifications to the secondary structure are often deleterious. At WC sites, we also find lower derived allele frequencies for mutations that abolish base pairing than for those that yield G·U “wobbles,” illustrating that weak base pairing can partially preserve the integrity of the secondary structure. Last, we show that WC sites under the strongest epistatic constraint reside in a three-stemmed pseudoknot motif that plays an essential role in programmed ribosomal frameshifting, whereas those under the weakest epistatic constraint are located in 3’ UTR motifs that regulate viral replication and pathogenicity. Our findings demonstrate the importance of epistasis in the evolution of the SARS-CoV-2 secondary structure, as well as highlight putative structural and functional targets of different forms of natural selection.
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Affiliation(s)
- Mahsa Alemrajabi
- Department of Physics, Florida Atlantic University, Boca Raton, FL, 33431, USA
| | - Ksenia Macias Calix
- Department of Electrical Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL, 33431, USA
| | - Raquel Assis
- Department of Electrical Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL, 33431, USA.
- Institute for Human Health and Disease Intervention, Florida Atlantic University, Boca Raton, FL, 33431, USA.
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29
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Zhao Y, Jaber VR, Lukiw WJ. SARS-CoV-2, long COVID, prion disease and neurodegeneration. Front Neurosci 2022; 16:1002770. [PMID: 36238082 PMCID: PMC9551214 DOI: 10.3389/fnins.2022.1002770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/07/2022] [Indexed: 11/30/2022] Open
Affiliation(s)
- Yuhai Zhao
- Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA, United States
- LSU Neuroscience Center, LSU Health Sciences Center, New Orleans, LA, United States
| | - Vivian R. Jaber
- LSU Neuroscience Center, LSU Health Sciences Center, New Orleans, LA, United States
| | - Walter J. Lukiw
- LSU Neuroscience Center, LSU Health Sciences Center, New Orleans, LA, United States
- Department of Ophthalmology, LSU Health Sciences Center, New Orleans, LA, United States
- Department of Neurology, LSU Health Sciences Center, New Orleans, LA, United States
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30
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Lukiw WJ, Jaber VR, Pogue AI, Zhao Y. SARS-CoV-2 Invasion and Pathological Links to Prion Disease. Biomolecules 2022; 12:1253. [PMID: 36139092 PMCID: PMC9496025 DOI: 10.3390/biom12091253] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 08/26/2022] [Accepted: 08/30/2022] [Indexed: 12/19/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the COVID-19 disease, is a highly infectious and transmissible viral pathogen that continues to impact human health globally. Nearly ~600 million people have been infected with SARS-CoV-2, and about half exhibit some degree of continuing health complication, generically referred to as long COVID. Lingering and often serious neurological problems for patients in the post-COVID-19 recovery period include brain fog, behavioral changes, confusion, delirium, deficits in intellect, cognition and memory issues, loss of balance and coordination, problems with vision, visual processing and hallucinations, encephalopathy, encephalitis, neurovascular or cerebrovascular insufficiency, and/or impaired consciousness. Depending upon the patient’s age at the onset of COVID-19 and other factors, up to ~35% of all elderly COVID-19 patients develop a mild-to-severe encephalopathy due to complications arising from a SARS-CoV-2-induced cytokine storm and a surge in cytokine-mediated pro-inflammatory and immune signaling. In fact, this cytokine storm syndrome: (i) appears to predispose aged COVID-19 patients to the development of other neurological complications, especially those who have experienced a more serious grade of COVID-19 infection; (ii) lies along highly interactive and pathological pathways involving SARS-CoV-2 infection that promotes the parallel development and/or intensification of progressive and often lethal neurological conditions, and (iii) is strongly associated with the symptomology, onset, and development of human prion disease (PrD) and other insidious and incurable neurological syndromes. This commentary paper will evaluate some recent peer-reviewed studies in this intriguing area of human SARS-CoV-2-associated neuropathology and will assess how chronic, viral-mediated changes to the brain and CNS contribute to cognitive decline in PrD and other progressive, age-related neurodegenerative disorders.
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Affiliation(s)
- Walter J. Lukiw
- LSU Neuroscience Center, Louisiana State University Health Science Center, New Orleans, LA 70112, USA
- Alchem Biotek Research, Toronto, ON M5S 1A8, Canada
- Department of Ophthalmology, LSU Health Science Center, New Orleans, LA 70112, USA
- Department Neurology, LSU Health Science Center, New Orleans, LA 70112, USA
| | - Vivian R. Jaber
- LSU Neuroscience Center, Louisiana State University Health Science Center, New Orleans, LA 70112, USA
| | | | - Yuhai Zhao
- LSU Neuroscience Center, Louisiana State University Health Science Center, New Orleans, LA 70112, USA
- Department of Cell Biology & Anatomy, LSU Health Science Center, New Orleans, LA 70112, USA
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31
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A comprehensive modelling approach to estimate the transmissibility of coronavirus and its variants from infected subjects in indoor environments. Sci Rep 2022; 12:14164. [PMID: 35986061 PMCID: PMC9389491 DOI: 10.1038/s41598-022-17693-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 07/29/2022] [Indexed: 12/04/2022] Open
Abstract
A central issue in assessing the airborne risk of COVID-19 infections in indoor spaces pertains to linking the viral load in infected subjects to the lung deposition probability in exposed individuals through comprehensive aerosol dynamics modelling. In this paper, we achieve this by combining aerosol processes (evaporation, dispersion, settling, lung deposition) with a novel double Poisson model to estimate the probability that at least one carrier particle containing at least one virion will be deposited in the lungs and infect a susceptible individual. Multiple emission scenarios are considered. Unlike the hitherto used single Poisson models, the double Poisson model accounts for fluctuations in the number of carrier particles deposited in the lung in addition to the fluctuations in the virion number per carrier particle. The model demonstrates that the risk of infection for 10-min indoor exposure increases from 1 to 50% as the viral load in the droplets ejected from the infected subject increases from 2 × 108 to 2 × 1010 RNA copies/mL. Being based on well-established aerosol science and statistical principles, the present approach puts airborne risk assessment methodology on a sound formalistic footing, thereby reducing avoidable epistemic uncertainties in estimating relative transmissibilities of different coronavirus variants quantified by different viral loads.
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32
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Hossain A, Akter S, Rashid AA, Khair S, Alam ASMRU. Unique mutations in SARS-CoV-2 omicron subvariants' non-spike proteins: Potential impact on viral pathogenesis and host immune evasion. Microb Pathog 2022; 170:105699. [PMID: 35944840 PMCID: PMC9356572 DOI: 10.1016/j.micpath.2022.105699] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 07/27/2022] [Accepted: 07/28/2022] [Indexed: 12/20/2022]
Affiliation(s)
- Anamica Hossain
- Department of Microbiology, University of Dhaka, Dhaka, 1000, Bangladesh
| | - Shammi Akter
- Department of Microbiology, University of Dhaka, Dhaka, 1000, Bangladesh
| | - Alfi Anjum Rashid
- Department of Microbiology, University of Dhaka, Dhaka, 1000, Bangladesh
| | - Sabik Khair
- Department of Microbiology, University of Dhaka, Dhaka, 1000, Bangladesh
| | - A S M Rubayet Ul Alam
- Department of Microbiology, Jashore University of Science and Technology, Jashore, 7408, Bangladesh.
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33
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Robins WP, Mekalanos JJ. Covariance predicts conserved protein residue interactions important for the emergence and continued evolution of SARS-CoV-2 as a human pathogen. PLoS One 2022; 17:e0270276. [PMID: 35895734 PMCID: PMC9328546 DOI: 10.1371/journal.pone.0270276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 06/07/2022] [Indexed: 12/03/2022] Open
Abstract
SARS-CoV-2 is one of three recognized coronaviruses (CoVs) that have caused epidemics or pandemics in the 21st century and that likely emerged from animal reservoirs. Differences in nucleotide and protein sequence composition within related β-coronaviruses are often used to better understand CoV evolution, host adaptation, and their emergence as human pathogens. Here we report the comprehensive analysis of amino acid residue changes that have occurred in lineage B β-coronaviruses that show covariance with each other. This analysis revealed patterns of covariance within conserved viral proteins that potentially define conserved interactions within and between core proteins encoded by SARS-CoV-2 related β-coronaviruses. We identified not only individual pairs but also networks of amino acid residues that exhibited statistically high frequencies of covariance with each other using an independent pair model followed by a tandem model approach. Using 149 different CoV genomes that vary in their relatedness, we identified networks of unique combinations of alleles that can be incrementally traced genome by genome within different phylogenic lineages. Remarkably, covariant residues and their respective regions most abundantly represented are implicated in the emergence of SARS-CoV-2 and are also enriched in dominant SARS-CoV-2 variants.
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Affiliation(s)
- William P. Robins
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
| | - John J. Mekalanos
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America
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34
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Sanyal D, Banerjee S, Bej A, Chowdhury VR, Uversky VN, Chowdhury S, Chattopadhyay K. An integrated understanding of the evolutionary and structural features of the SARS-CoV-2 spike receptor binding domain (RBD). Int J Biol Macromol 2022; 217:492-505. [PMID: 35841961 PMCID: PMC9278002 DOI: 10.1016/j.ijbiomac.2022.07.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/29/2022] [Accepted: 07/04/2022] [Indexed: 12/23/2022]
Abstract
Conventional drug development strategies typically use pocket in protein structures as drug-target sites. They overlook the plausible effects of protein evolvability and resistant mutations on protein structure which in turn may impair protein-drug interaction. In this study, we used an integrated evolution and structure guided strategy to develop potential evolutionary-escape resistant therapeutics using receptor binding domain (RBD) of SARS-CoV-2 spike-protein/S-protein as a model. Deploying an ensemble of sequence space exploratory tools including co-evolutionary analysis and deep mutational scans we provide a quantitative insight into the evolutionarily constrained subspace of the RBD sequence-space. Guided by molecular simulation and structure network analysis we highlight regions inside the RBD, which are critical for providing structural integrity and conformational flexibility. Using fuzzy C-means clustering we combined evolutionary and structural features of RBD and identified a critical region. Subsequently, we used computational drug screening using a library of 1615 small molecules and identified one lead molecule, which is expected to target the identified region, critical for evolvability and structural stability of RBD. This integrated evolution-structure guided strategy to develop evolutionary-escape resistant lead molecules have potential general applications beyond SARS-CoV-2.
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Affiliation(s)
- Dwipanjan Sanyal
- Protein Folding and Dynamics Group, Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India
| | - Suharto Banerjee
- Protein Folding and Dynamics Group, Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India
| | - Aritra Bej
- Protein Folding and Dynamics Group, Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India
| | - Vaidehi Roy Chowdhury
- Protein Folding and Dynamics Group, Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA; Laboratory of New Methods in Biology, Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow region 142290, Russia
| | - Sourav Chowdhury
- Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
| | - Krishnananda Chattopadhyay
- Protein Folding and Dynamics Group, Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India.
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35
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Barman RK, Mukhopadhyay A, Maulik U, Das S. A network biology approach to identify crucial host targets for COVID-19. Methods 2022; 203:108-115. [PMID: 35364279 PMCID: PMC8960288 DOI: 10.1016/j.ymeth.2022.03.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 03/09/2022] [Accepted: 03/27/2022] [Indexed: 12/23/2022] Open
Abstract
The ongoing global pandemic of COVID-19, caused by SARS-CoV-2 has killed more than 5.9 million individuals out of ∼43 million confirmed infections. At present, several parts of the world are encountering the 3rd wave. Mass vaccination has been started in several countries but they are less likely to be broadly available for the current pandemic, repurposing of the existing drugs has drawn highest attention for an immediate solution. A recent publication has mapped the physical interactions of SARS-CoV-2 and human proteins by affinity-purification mass spectrometry (AP-MS) and identified 332 high-confidence SARS-CoV-2-human protein-protein interactions (PPIs). Here, we taken a network biology approach and constructed a human protein-protein interaction network (PPIN) with the above SARS-CoV-2 targeted proteins. We utilized a combination of essential network centrality measures and functional properties of the human proteins to identify the critical human targets of SARS-CoV-2. Four human proteins, namely PRKACA, RHOA, CDK5RAP2, and CEP250 have emerged as the best therapeutic targets, of which PRKACA and CEP250 were also found by another group as potential candidates for drug targets in COVID-19. We further found candidate drugs/compounds, such as guanosine triphosphate, remdesivir, adenosine monophosphate, MgATP, and H-89 dihydrochloride that bind the target human proteins. The urgency to prevent the spread of infection and the death of diseased individuals has prompted the search for agents from the pool of approved drugs to repurpose them for COVID-19. Our results indicate that host targeting therapy with the repurposed drugs may be a useful strategy for the treatment of SARS-CoV-2 infection.
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Affiliation(s)
- Ranjan Kumar Barman
- Division of Virology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata 700010, India; Department of Computer Science and Engineering, Jadavpur University, Kolkata 700032, India
| | - Anirban Mukhopadhyay
- Department of Computer Science and Engineering, University of Kalyani, Kalyani 741235, West Bengal, India
| | - Ujjwal Maulik
- Department of Computer Science and Engineering, Jadavpur University, Kolkata 700032, India
| | - Santasabuj Das
- Division of Clinical Medicine, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata 700010, India; ICMR-National Institute of Occupational Health, Ahmedabad 380016, India.
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36
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Rojas Chávez RA, Fili M, Han C, Rahman SA, Bicar IGL, Gregory S, Hu G, Das J, Brown GD, Haim H. Mutability Patterns Across the Spike Glycoprotein Reveal the Diverging and Lineage-specific Evolutionary Space of SARS-CoV-2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2022:2022.02.01.478697. [PMID: 35132415 PMCID: PMC8820662 DOI: 10.1101/2022.02.01.478697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Mutations in the spike glycoprotein of SARS-CoV-2 allow the virus to probe the sequence space in search of higher-fitness states. New sublineages of SARS-CoV-2 variants-of-concern (VOCs) continuously emerge with such mutations. Interestingly, the sites of mutation in these sublineages vary between the VOCs. Whether such differences reflect the random nature of mutation appearance or distinct evolutionary spaces of spike in the VOCs is unclear. Here we show that each position of spike has a lineage-specific likelihood for mutations to appear and dominate descendent sublineages. This likelihood can be accurately estimated from the lineage-specific mutational profile of spike at a protein-wide level. The mutability environment of each position, including adjacent sites on the protein structure and neighboring sites on the network of comutability, accurately forecast changes in descendent sublineages. Mapping of imminent changes within the VOCs can contribute to the design of immunogens and therapeutics that address future forms of SARS-CoV-2.
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37
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Miller NL, Raman R, Clark T, Sasisekharan R. Complexity of Viral Epitope Surfaces as Evasive Targets for Vaccines and Therapeutic Antibodies. Front Immunol 2022; 13:904609. [PMID: 35784339 PMCID: PMC9247215 DOI: 10.3389/fimmu.2022.904609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 05/16/2022] [Indexed: 11/29/2022] Open
Abstract
The dynamic interplay between virus and host plays out across many interacting surfaces as virus and host evolve continually in response to one another. In particular, epitope-paratope interactions (EPIs) between viral antigen and host antibodies drive much of this evolutionary race. In this review, we describe a series of recent studies examining aspects of epitope complexity that go beyond two interacting protein surfaces as EPIs are typically understood. To structure our discussion, we present a framework for understanding epitope complexity as a spectrum along a series of axes, focusing primarily on 1) epitope biochemical complexity (e.g., epitopes involving N-glycans) and 2) antigen conformational/dynamic complexity (e.g., epitopes with differential properties depending on antigen state or fold-axis). We highlight additional epitope complexity factors including epitope tertiary/quaternary structure, which contribute to epistatic relationships between epitope residues within- or adjacent-to a given epitope, as well as epitope overlap resulting from polyclonal antibody responses, which is relevant when assessing antigenic pressure against a given epitope. Finally, we discuss how these different forms of epitope complexity can limit EPI analyses and therapeutic antibody development, as well as recent efforts to overcome these limitations.
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Affiliation(s)
- Nathaniel L. Miller
- Harvard Massachusetts Institute of Technology (MIT) Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Rahul Raman
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Thomas Clark
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Ram Sasisekharan
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States
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38
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Martínez-González B, Soria ME, Vázquez-Sirvent L, Ferrer-Orta C, Lobo-Vega R, Mínguez P, de la Fuente L, Llorens C, Soriano B, Ramos-Ruíz R, Cortón M, López-Rodríguez R, García-Crespo C, Somovilla P, Durán-Pastor A, Gallego I, de Ávila AI, Delgado S, Morán F, López-Galíndez C, Gómez J, Enjuanes L, Salar-Vidal L, Esteban-Muñoz M, Esteban J, Fernández-Roblas R, Gadea I, Ayuso C, Ruíz-Hornillos J, Verdaguer N, Domingo E, Perales C. SARS-CoV-2 Mutant Spectra at Different Depth Levels Reveal an Overwhelming Abundance of Low Frequency Mutations. Pathogens 2022; 11:662. [PMID: 35745516 PMCID: PMC9227345 DOI: 10.3390/pathogens11060662] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/02/2022] [Accepted: 06/06/2022] [Indexed: 12/23/2022] Open
Abstract
Populations of RNA viruses are composed of complex and dynamic mixtures of variant genomes that are termed mutant spectra or mutant clouds. This applies also to SARS-CoV-2, and mutations that are detected at low frequency in an infected individual can be dominant (represented in the consensus sequence) in subsequent variants of interest or variants of concern. Here we briefly review the main conclusions of our work on mutant spectrum characterization of hepatitis C virus (HCV) and SARS-CoV-2 at the nucleotide and amino acid levels and address the following two new questions derived from previous results: (i) how is the SARS-CoV-2 mutant and deletion spectrum composition in diagnostic samples, when examined at progressively lower cut-off mutant frequency values in ultra-deep sequencing; (ii) how the frequency distribution of minority amino acid substitutions in SARS-CoV-2 compares with that of HCV sampled also from infected patients. The main conclusions are the following: (i) the number of different mutations found at low frequency in SARS-CoV-2 mutant spectra increases dramatically (50- to 100-fold) as the cut-off frequency for mutation detection is lowered from 0.5% to 0.1%, and (ii) that, contrary to HCV, SARS-CoV-2 mutant spectra exhibit a deficit of intermediate frequency amino acid substitutions. The possible origin and implications of mutant spectrum differences among RNA viruses are discussed.
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Affiliation(s)
- Brenda Martínez-González
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
- Department of Molecular and Cell Biology, Centro Nacional de Biotecnología (CNB-CSIC), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain;
| | - María Eugenia Soria
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (C.G.-C.); (P.S.); (A.D.-P.); (I.G.); (A.I.d.Á.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain;
| | - Lucía Vázquez-Sirvent
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
| | - Cristina Ferrer-Orta
- Structural Biology Department, Institut de Biología Molecular de Barcelona CSIC, 08028 Barcelona, Spain; (C.F.-O.); (N.V.)
| | - Rebeca Lobo-Vega
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
| | - Pablo Mínguez
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (P.M.); (L.d.l.F.); (M.C.); (R.L.-R.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Bioinformatics Unit, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain
| | - Lorena de la Fuente
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (P.M.); (L.d.l.F.); (M.C.); (R.L.-R.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Bioinformatics Unit, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain
| | - Carlos Llorens
- Biotechvana, “Scientific Park”, Universidad de Valencia, 46980 Valencia, Spain; (C.L.); (B.S.)
| | - Beatriz Soriano
- Biotechvana, “Scientific Park”, Universidad de Valencia, 46980 Valencia, Spain; (C.L.); (B.S.)
| | - Ricardo Ramos-Ruíz
- Unidad de Genómica, “Scientific Park of Madrid”, Campus de Cantoblanco, 28049 Madrid, Spain;
| | - Marta Cortón
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (P.M.); (L.d.l.F.); (M.C.); (R.L.-R.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Rosario López-Rodríguez
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (P.M.); (L.d.l.F.); (M.C.); (R.L.-R.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Carlos García-Crespo
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (C.G.-C.); (P.S.); (A.D.-P.); (I.G.); (A.I.d.Á.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain;
| | - Pilar Somovilla
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (C.G.-C.); (P.S.); (A.D.-P.); (I.G.); (A.I.d.Á.)
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain
| | - Antoni Durán-Pastor
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (C.G.-C.); (P.S.); (A.D.-P.); (I.G.); (A.I.d.Á.)
| | - Isabel Gallego
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (C.G.-C.); (P.S.); (A.D.-P.); (I.G.); (A.I.d.Á.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain;
| | - Ana Isabel de Ávila
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (C.G.-C.); (P.S.); (A.D.-P.); (I.G.); (A.I.d.Á.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain;
| | - Soledad Delgado
- Departamento de Sistemas Informáticos, Escuela Técnica Superior de Ingeniería de Sistemas Informáticos (ETSISI), Universidad Politécnica de Madrid, 28031 Madrid, Spain;
| | - Federico Morán
- Departamento de Bioquímica y Biología Molecular, Universidad Complutense de Madrid, 28005 Madrid, Spain;
| | - Cecilio López-Galíndez
- Unidad de Virología Molecular, Laboratorio de Referencia e Investigación en Retrovirus, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28222 Madrid, Spain;
| | - Jordi Gómez
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Instituto de Parasitología y Biomedicina ‘López-Neyra’ (CSIC), Parque Tecnológico Ciencias de la Salud, Armilla, 18016 Granada, Spain
| | - Luis Enjuanes
- Department of Molecular and Cell Biology, Centro Nacional de Biotecnología (CNB-CSIC), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain;
| | - Llanos Salar-Vidal
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
| | - Mario Esteban-Muñoz
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
| | - Jaime Esteban
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
| | - Ricardo Fernández-Roblas
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
| | - Ignacio Gadea
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
| | - Carmen Ayuso
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (P.M.); (L.d.l.F.); (M.C.); (R.L.-R.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Javier Ruíz-Hornillos
- Allergy Unit, Hospital Infanta Elena, Valdemoro, 28342 Madrid, Spain;
- Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain
- Faculty of Medicine, Universidad Francisco de Vitoria, 28223 Madrid, Spain
| | - Nuria Verdaguer
- Structural Biology Department, Institut de Biología Molecular de Barcelona CSIC, 08028 Barcelona, Spain; (C.F.-O.); (N.V.)
| | - Esteban Domingo
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (C.G.-C.); (P.S.); (A.D.-P.); (I.G.); (A.I.d.Á.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain;
| | - Celia Perales
- Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040 Madrid, Spain; (B.M.-G.); (M.E.S.); (L.V.-S.); (R.L.-V.); (L.S.-V.); (M.E.-M.); (J.E.); (R.F.-R.); (I.G.)
- Department of Molecular and Cell Biology, Centro Nacional de Biotecnología (CNB-CSIC), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain;
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain;
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Abstract
Our understanding of the still unfolding severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic would have been extremely limited without the study of the genetics and evolution of this new human coronavirus. Large-scale genome-sequencing efforts have provided close to real-time tracking of the global spread and diversification of SARS-CoV-2 since its entry into the human population in late 2019. These data have underpinned analysis of its origins, epidemiology, and adaptations to the human population: principally immune evasion and increasing transmissibility. SARS-CoV-2, despite being a new human pathogen, was highly capable of human-to-human transmission. During its rapid spread in humans, SARS-CoV-2 has evolved independent new forms, the so-called "variants of concern," that are better optimized for human-to-human transmission. The most important adaptation of the bat coronavirus progenitor of both SARS-CoV-1 and SARS-CoV-2 for human infection (and other mammals) is the use of the angiotensin-converting enzyme 2 (ACE2) receptor. Relaxed structural constraints provide plasticity to SARS-related coronavirus spike protein permitting it to accommodate significant amino acid replacements of antigenic consequence without compromising the ability to bind to ACE2. Although the bulk of research has justifiably concentrated on the viral spike protein as the main determinant of antigenic evolution and changes in transmissibility, there is accumulating evidence for the contribution of other regions of the viral proteome to virus-host interaction. Whereas levels of community transmission of recombinants compromising genetically distinct variants are at present low, when divergent variants cocirculate, recombination between SARS-CoV-2 clades is being detected, increasing the risk that viruses with new properties emerge. Applying computational and machine learning methods to genome sequence data sets to generate experimentally verifiable predictions will serve as an early warning system for novel variant surveillance and will be important in future vaccine planning. Omicron, the latest SARS-CoV-2 variant of concern, has focused attention on step change antigenic events, "shift," as opposed to incremental "drift" changes in antigenicity. Both an increase in transmissibility and antigenic shift in Omicron led to it readily causing infections in the fully vaccinated and/or previously infected. Omicron's virulence, while reduced relative to the variant of concern it replaced, Delta, is very much premised on the past immune exposure of individuals with a clear signal that boosted vaccination protects from severe disease. Currently, SARS-CoV-2 has proven itself to be a dangerous new human respiratory pathogen with an unpredictable evolutionary capacity, leading to a risk of future variants too great not to ensure all regions of the world are screened by viral genome sequencing, protected through available and affordable vaccines, and have non-punitive strategies in place for detecting and responding to novel variants of concern.
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Affiliation(s)
- Amalio Telenti
- Vir Biotechnology, San Francisco, California 94158, USA
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, California 92037, USA
| | - Emma B Hodcroft
- Institute of Social and Preventive Medicine, University of Bern, 3012 Bern, Switzerland
- Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - David L Robertson
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow G61 1QH, UK
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Identifying SARS-CoV-2 Variants of Concern through Saliva-Based RT-qPCR by Targeting Recurrent Mutation Sites. Microbiol Spectr 2022; 10:e0079722. [PMID: 35546574 PMCID: PMC9241879 DOI: 10.1128/spectrum.00797-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
SARS-CoV-2 variants of concern (VOCs) continue to pose a public health threat which necessitates a real-time monitoring strategy to complement whole genome sequencing. Thus, we investigated the efficacy of competitive probe RT-qPCR assays for six mutation sites identified in SARS-CoV-2 VOCs and, after validating the assays with synthetic RNA, performed these assays on positive saliva samples. When compared with whole genome sequence results, the SΔ69-70 and ORF1aΔ3675-3677 assays demonstrated 93.60 and 68.00% accuracy, respectively. The SNP assays (K417T, E484K, E484Q, L452R) demonstrated 99.20, 96.40, 99.60, and 96.80% accuracies, respectively. Lastly, we screened 345 positive saliva samples from 7 to 22 December 2021 using Omicron-specific mutation assays and were able to quickly identify rapid spread of Omicron in Upstate South Carolina. Our workflow demonstrates a novel approach for low-cost, real-time population screening of VOCs. IMPORTANCE SARS-CoV-2 variants of concern and their many sublineages can be characterized by mutations present within their genetic sequences. These mutations can provide selective advantages such as increased transmissibility and antibody evasion, which influences public health recommendations such as mask mandates, quarantine requirements, and treatment regimens. Our RT-qPCR workflow allows for strain identification of SARS-CoV-2 positive saliva samples by targeting common mutation sites shared between variants of concern and detecting single nucleotides present at the targeted location. This differential diagnostic system can quickly and effectively identify a wide array of SARS-CoV-2 strains, which can provide more informed public health surveillance strategies in the future.
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41
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Fung KM, Lai SJ, Lin TL, Tseng TS. Antigen–Antibody Complex-Guided Exploration of the Hotspots Conferring the Immune-Escaping Ability of the SARS-CoV-2 RBD. Front Mol Biosci 2022; 9:797132. [PMID: 35392535 PMCID: PMC8981523 DOI: 10.3389/fmolb.2022.797132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 03/02/2022] [Indexed: 11/24/2022] Open
Abstract
The COVID-19 pandemic resulting from the spread of SARS-CoV-2 spurred devastating health and economic crises around the world. Neutralizing antibodies and licensed vaccines were developed to combat COVID-19, but progress was slow. In addition, variants of the receptor-binding domain (RBD) of the spike protein confer resistance of SARS-CoV-2 to neutralizing antibodies, nullifying the possibility of human immunity. Therefore, investigations into the RBD mutations that disrupt neutralization through convalescent antibodies are urgently required. In this study, we comprehensively and systematically investigated the binding stability of RBD variants targeting convalescent antibodies and revealed that the RBD residues F456, F490, L452, L455, and K417 are immune-escaping hotspots, and E484, F486, and N501 are destabilizing residues. Our study also explored the possible modes of actions of emerging SARS-CoV-2 variants. All results are consistent with experimental observations of attenuated antibody neutralization and clinically emerging SARS-CoV-2 variants. We identified possible immune-escaping hotspots that could further promote resistance to convalescent antibodies. The results provide valuable information for developing and designing novel monoclonal antibody drugs to combat emerging SARS-CoV-2 variants.
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Affiliation(s)
- Kit-Man Fung
- Academia Sinica, Institute of Biological Chemistry, Taipei, Taiwan
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
| | - Shu-Jung Lai
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
| | - Tzu-Lu Lin
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
| | - Tien-Sheng Tseng
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
- *Correspondence: Tien-Sheng Tseng,
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42
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Ham RE, Smothers AR, Che R, Sell KJ, Peng CA, Dean D. Identifying SARS-CoV-2 Variants of Concern through saliva-based RT-qPCR by targeting recurrent mutation sites.. [PMID: 35262087 PMCID: PMC8902870 DOI: 10.1101/2022.03.02.22271785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
AbstractSARS-CoV-2 variants of concern (VOCs) continue to pose a public health threat which necessitates a real-time monitoring strategy to compliment whole genome sequencing. Thus, we investigated the efficacy of competitive probe RT-qPCR assays for six mutation sites identified in SARS-CoV-2 VOCs and, after validating the assays with synthetic RNA, performed these assays on positive saliva samples. When compared with whole genome sequence results, the SΔ69-70 and ORF1aΔ3675-3677 assays demonstrated 93.60% and 68.00% accuracy, respectively. The SNP assays (K417T, E484K, E484Q, L452R) demonstrated 99.20%, 96.40%, 99.60%, and 96.80% accuracies, respectively. Lastly, we screened 345 positive saliva samples from December 7-22, 2021 using Omicron-specific mutation assays and were able to quickly identify rapid spread of Omicron in Upstate South Carolina. Our workflow demonstrates a novel approach for low-cost, real-time population screening of VOCs.ImportanceSARS-CoV-2 variants of concern and their many sublineages can be characterized by mutations present within their genetic sequences. These mutations can provide selective advantages such as increased transmissibility and antibody evasion, which influences public health recommendations such as mask mandates, quarantine requirements, and treatment regimens. Our real-time RT-qPCR workflow allows for strain identification of SARS-CoV-2 positive saliva samples by targeting common mutation sites shared between VOCs and detecting single nucleotides present at the targeted location. This differential diagnostic system can quickly and effectively identify a wide array of SARS-CoV-2 strains, which can provide more informed public health surveillance strategies in the future.
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43
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Tubiana J, Xiang Y, Fan L, Wolfson HJ, Chen K, Schneidman-Duhovny D, Shi Y. Reduced antigenicity of Omicron lowers host serologic response. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2022. [PMID: 35194608 PMCID: PMC8863144 DOI: 10.1101/2022.02.15.480546] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
SARS-CoV-2 Omicron variant of concern (VOC) contains fifteen mutations on the receptor binding domain (RBD), evading most neutralizing antibodies from vaccinated sera. Emerging evidence suggests that Omicron breakthrough cases are associated with substantially lower antibody titers than other VOC cases. However, the mechanism remains unclear. Here, using a novel geometric deep-learning model, we discovered that the antigenic profile of Omicron RBD is distinct from the prior VOCs, featuring reduced antigenicity in its remodeled receptor binding sites (RBS). To substantiate our deep-learning prediction, we immunized mice with different recombinant RBD variants and found that the Omicron's extensive mutations can lead to a drastically attenuated serologic response with limited neutralizing activity in vivo , while the T cell response remains potent. Analyses of serum cross-reactivity and competitive ELISA with epitope-specific nanobodies revealed that the antibody response to Omicron was reduced across RBD epitopes, including both the variable RBS and epitopes without any known VOC mutations. Moreover, computational modeling confirmed that the RBS is highly versatile with a capacity to further decrease antigenicity while retaining efficient receptor binding. Longitudinal analysis showed that this evolutionary trend of decrease in antigenicity was also found in hCoV229E, a common cold coronavirus that has been circulating in humans for decades. Thus, our study provided unprecedented insights into the reduced antibody titers associated with Omicron infection, revealed a possible trajectory of future viral evolution and may inform the vaccine development against future outbreaks.
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Robins WP, Mekalanos JJ. Covariance predicts conserved protein residue interactions important to the emergence and continued evolution of SARS-CoV-2 as a human pathogen.. [PMID: 35169805 PMCID: PMC8845505 DOI: 10.1101/2022.01.13.476204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
SARS-CoV-2 is one of three recognized coronaviruses (CoVs) that have caused epidemics or pandemics in the 21st century and that likely emerged from animal reservoirs. Differences in nucleotide and protein sequence composition within related β-coronaviruses are often used to better understand CoV evolution, host adaptation, and their emergence as human pathogens. Here we report the comprehensive analysis of amino acid residue changes that have occurred in lineage B β-coronaviruses that show covariance with each other. This analysis revealed patterns of covariance within conserved viral proteins that potentially define conserved interactions within and between core proteins encoded by SARS-CoV-2 related β-coranaviruses. We identified not only individual pairs but also networks of amino acid residues that exhibited statistically high frequencies of covariance with each other using an independent pair model followed by a tandem model approach. Using 149 different CoV genomes that vary in their relatedness, we identified networks of unique combinations of alleles that can be incrementally traced genome by genome within different phylogenic lineages. Remarkably, covariant residues and their respective regions most abundantly represented are implicated in the emergence of SARS-CoV-2 are also enriched in dominant SARS-CoV-2 variants.
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