Comprehensive analysis of the host-virus interactome of SARS-CoV-2

Host-virus protein-protein interaction is the key component of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lifecycle. We conducted a comprehensive interactome study between the virus and host cells using tandem affinity purification and proximity labeling strategies and identified 437 human proteins as the high-confidence interacting proteins. Functional characterization and further validation of these interactions elucidated how distinct SARS-CoV-2 viral proteins participate in its lifecycle, and discovered potential drug targets to the treatment of COVID-19. The interactomes of two key SARS-CoV-2 encoded viral proteins, NSP1 and N protein, were compared with the interactomes of their counterparts in other human coronaviruses. These comparisons not only revealed common host pathways these viruses manipulate for their survival, but also showed divergent protein-protein interactions that may explain differences in disease pathology. This comprehensive interactome of coronavirus disease-2019 provides valuable resources for understanding and treating this disease.

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A SARS-CoV-2 – host proximity interactome

10.1101/2020.09.03.282103 ◽

2020 ◽

Cited By ~ 3

Author(s):

Payman Samavarchi-Tehrani ◽

Hala Abdouni ◽

James D.R. Knight ◽

Audrey Astori ◽

Reuben Samson ◽

...

Keyword(s):

Host Cell ◽

Protein Interactions ◽

Affinity Purification ◽

Drug Repurposing ◽

Viral Proteins ◽

Host Protein ◽

Virus Protein ◽

Host Proteins ◽

Biochemical Purification ◽

Cell Functions

AbstractViral replication is dependent on interactions between viral polypeptides and host proteins. Identifying virus-host protein interactions can thus uncover unique opportunities for interfering with the virus life cycle via novel drug compounds or drug repurposing. Importantly, many viral-host protein interactions take place at intracellular membranes and poorly soluble organelles, which are difficult to profile using classical biochemical purification approaches. Applying proximity-dependent biotinylation (BioID) with the fast-acting miniTurbo enzyme to 27 SARS-CoV-2 proteins in a lung adenocarcinoma cell line (A549), we detected 7810 proximity interactions (7382 of which are new for SARS-CoV-2) with 2242 host proteins (results available at covid19interactome.org). These results complement and dramatically expand upon recent affinity purification-based studies identifying stable host-virus protein complexes, and offer an unparalleled view of membrane-associated processes critical for viral production. Host cell organellar markers were also subjected to BioID in parallel, allowing us to propose modes of action for several viral proteins in the context of host proteome remodelling. In summary, our dataset identifies numerous high confidence proximity partners for SARS-CoV-2 viral proteins, and describes potential mechanisms for their effects on specific host cell functions.

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Mapping the SARS-CoV-2–Host Protein–Protein Interactome by Affinity Purification Mass Spectrometry and Proximity-Dependent Biotin Labeling: A Rational and Straightforward Route to Discover Host-Directed Anti-SARS-CoV-2 Therapeutics

International Journal of Molecular Sciences ◽

10.3390/ijms22020532 ◽

2021 ◽

Vol 22 (2) ◽

pp. 532

Author(s):

Rosa Terracciano ◽

Mariaimmacolata Preianò ◽

Annalisa Fregola ◽

Corrado Pelaia ◽

Tiziana Montalcini ◽

...

Keyword(s):

Mass Spectrometry ◽

Drug Discovery ◽

Protein Interactions ◽

Drug Targets ◽

Affinity Purification ◽

Drug Repurposing ◽

Host Protein ◽

Host Cells ◽

Traditional Drug ◽

Approved Drugs

Protein–protein interactions (PPIs) are the vital engine of cellular machinery. After virus entry in host cells the global organization of the viral life cycle is strongly regulated by the formation of virus-host protein interactions. With the advent of high-throughput -omics platforms, the mirage to obtain a “high resolution” view of virus–host interactions has come true. In fact, the rapidly expanding approaches of mass spectrometry (MS)-based proteomics in the study of PPIs provide efficient tools to identify a significant number of potential drug targets. Generation of PPIs maps by affinity purification-MS and by the more recent proximity labeling-MS may help to uncover cellular processes hijacked and/or altered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), providing promising therapeutic targets. The possibility to further validate putative key targets from high-confidence interactions between viral bait and host protein through follow-up MS-based multi-omics experiments offers an unprecedented opportunity in the drug discovery pipeline. In particular, drug repurposing, making use of already existing approved drugs directly targeting these identified and validated host interactors, might shorten the time and reduce the costs in comparison to the traditional drug discovery process. This route might be promising for finding effective antiviral therapeutic options providing a turning point in the fight against the coronavirus disease-2019 (COVID-19) outbreak.

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A SARS-CoV-2-Human Protein-Protein Interaction Map Reveals Drug Targets and Potential Drug-Repurposing

10.1101/2020.03.22.002386 ◽

2020 ◽

Cited By ~ 73

Author(s):

David E. Gordon ◽

Gwendolyn M. Jang ◽

Mehdi Bouhaddou ◽

Jiewei Xu ◽

Kirsten Obernier ◽

...

Keyword(s):

Protein Interactions ◽

Drug Targets ◽

Affinity Purification ◽

Drug Repurposing ◽

Human Protein ◽

Protein Protein Interaction ◽

Human Proteins ◽

Interaction Map ◽

Novel Coronavirus ◽

Approved Drugs

ABSTRACTAn outbreak of the novel coronavirus SARS-CoV-2, the causative agent of COVID-19 respiratory disease, has infected over 290,000 people since the end of 2019, killed over 12,000, and caused worldwide social and economic disruption1,2. There are currently no antiviral drugs with proven efficacy nor are there vaccines for its prevention. Unfortunately, the scientific community has little knowledge of the molecular details of SARS-CoV-2 infection. To illuminate this, we cloned, tagged and expressed 26 of the 29 viral proteins in human cells and identified the human proteins physically associated with each using affinity-purification mass spectrometry (AP-MS), which identified 332 high confidence SARS-CoV-2-human protein-protein interactions (PPIs). Among these, we identify 66 druggable human proteins or host factors targeted by 69 existing FDA-approved drugs, drugs in clinical trials and/or preclinical compounds, that we are currently evaluating for efficacy in live SARS-CoV-2 infection assays. The identification of host dependency factors mediating virus infection may provide key insights into effective molecular targets for developing broadly acting antiviral therapeutics against SARS-CoV-2 and other deadly coronavirus strains.

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Native Structure-Based Peptides as Potential Protein–Protein Interaction Inhibitors of SARS-CoV-2 Spike Protein and Human ACE2 Receptor

Molecules ◽

10.3390/molecules26082157 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2157

Author(s):

Norbert Odolczyk ◽

Ewa Marzec ◽

Maria Winiewska-Szajewska ◽

Jarosław Poznański ◽

Piotr Zielenkiewicz

Keyword(s):

Drug Development ◽

Protein Interactions ◽

Rna Virus ◽

Antiviral Drug ◽

Host Protein ◽

Host Cells ◽

Cell Surface Receptor ◽

Short Peptides ◽

Virus Protein ◽

Positive Strand Rna

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is a positive-strand RNA virus that causes severe respiratory syndrome in humans, which is now referred to as coronavirus disease 2019 (COVID-19). Since December 2019, the new pathogen has rapidly spread globally, with over 65 million cases reported to the beginning of December 2020, including over 1.5 million deaths. Unfortunately, currently, there is no specific and effective treatment for COVID-19. As SARS-CoV-2 relies on its spike proteins (S) to bind to a host cell-surface receptor angiotensin-converting enzyme-2(ACE2), and this interaction is proved to be responsible for entering a virus into host cells, it makes an ideal target for antiviral drug development. In this work, we design three very short peptides based on the ACE2 sequence/structure fragments, which may effectively bind to the receptor-binding domain (RBD) of S protein and may, in turn, disrupt the important virus-host protein–protein interactions, blocking early steps of SARS-CoV-2 infection. Two of our peptides bind to virus protein with affinity in nanomolar range, and as very short peptides have great potential for drug development.

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Universal Screening Methods and Applications of ThermoFluor®

CrossRef Listing of Deleted DOIs ◽

10.1177/1087057106292746 ◽

2006 ◽

Vol 11 (7) ◽

pp. 854-863 ◽

Cited By ~ 124

Author(s):

Maxwell D. Cummings ◽

Michael A. Farnum ◽

Marina I. Nelen

Keyword(s):

Protein Interactions ◽

Protein Function ◽

Protein Unfolding ◽

Direct Detection ◽

Functional Characterization ◽

Screening Methods ◽

Protein Protein Interactions ◽

Protein Protein Interaction ◽

Bacterial Enzyme ◽

Research Problems

The genomics revolution has unveiled a wealth of poorly characterized proteins. Scientists are often able to produce milligram quantities of proteins for which function is unknown or hypothetical, based only on very distant sequence homology. Broadly applicable tools for functional characterization are essential to the illumination of these orphan proteins. An additional challenge is the direct detection of inhibitors of protein-protein interactions (and allosteric effectors). Both of these research problems are relevant to, among other things, the challenge of finding and validating new protein targets for drug action. Screening collections of small molecules has long been used in the pharmaceutical industry as 1 method of discovering drug leads. Screening in this context typically involves a function-based assay. Given a sufficient quantity of a protein of interest, significant effort may still be required for functional characterization, assay development, and assay configuration for screening. Increasingly, techniques are being reported that facilitate screening for specific ligands for a protein of unknown function. Such techniques also allow for function-independent screening with better characterized proteins. ThermoFluor®, a screening instrument based on monitoring ligand effects on temperature-dependent protein unfolding, can be applied when protein function is unknown. This technology has proven useful in the decryption of an essential bacterial enzyme and in the discovery of a series of inhibitors of a cancer-related, protein-protein interaction. The authors review some of the tools relevant to these research problems in drug discovery, and describe our experiences with 2 different proteins.

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Trifunctional cross-linker for mapping protein-protein interaction networks and comparing protein conformational states

eLife ◽

10.7554/elife.12509 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 56

Author(s):

Dan Tan ◽

Qiang Li ◽

Mei-Jun Zhang ◽

Chao Liu ◽

Chengying Ma ◽

...

Keyword(s):

Protein Interactions ◽

Structural Information ◽

Affinity Purification ◽

Protein Protein Interactions ◽

C Elegans ◽

Protein Protein Interaction ◽

Lysine Residues ◽

Spacer Arm ◽

Cross Linker ◽

Protein Nucleic Acid

To improve chemical cross-linking of proteins coupled with mass spectrometry (CXMS), we developed a lysine-targeted enrichable cross-linker containing a biotin tag for affinity purification, a chemical cleavage site to separate cross-linked peptides away from biotin after enrichment, and a spacer arm that can be labeled with stable isotopes for quantitation. By locating the flexible proteins on the surface of 70S ribosome, we show that this trifunctional cross-linker is effective at attaining structural information not easily attainable by crystallography and electron microscopy. From a crude Rrp46 immunoprecipitate, it helped identify two direct binding partners of Rrp46 and 15 protein-protein interactions (PPIs) among the co-immunoprecipitated exosome subunits. Applying it to E. coli and C. elegans lysates, we identified 3130 and 893 inter-linked lysine pairs, representing 677 and 121 PPIs. Using a quantitative CXMS workflow we demonstrate that it can reveal changes in the reactivity of lysine residues due to protein-nucleic acid interaction.

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PIPINO: A Software Package to Facilitate the Identification of Protein-Protein Interactions from Affinity Purification Mass Spectrometry Data

BioMed Research International ◽

10.1155/2016/2891918 ◽

2016 ◽

Vol 2016 ◽

pp. 1-13

Author(s):

Stefan Kalkhof ◽

Stefan Schildbach ◽

Conny Blumert ◽

Friedemann Horn ◽

Martin von Bergen ◽

...

Keyword(s):

Mass Spectrometry ◽

Protein Interactions ◽

Isotope Labeling ◽

Affinity Purification ◽

Interaction Network ◽

Mass Spectrometry Data ◽

Protein Protein Interactions ◽

Protein Protein Interaction ◽

Binding Behavior ◽

Bona Fide

The functionality of most proteins is regulated by protein-protein interactions. Hence, the comprehensive characterization of the interactome is the next milestone on the path to understand the biochemistry of the cell. A powerful method to detect protein-protein interactions is a combination of coimmunoprecipitation or affinity purification with quantitative mass spectrometry. Nevertheless, both methods tend to precipitate a high number of background proteins due to nonspecific interactions. To address this challenge the software Protein-Protein-Interaction-Optimizer (PIPINO) was developed to perform an automated data analysis, to facilitate the selection of bona fide binding partners, and to compare the dynamic of interaction networks. In this study we investigated the STAT1 interaction network and its activation dependent dynamics. Stable isotope labeling by amino acids in cell culture (SILAC) was applied to analyze the STAT1 interactome after streptavidin pull-down of biotagged STAT1 from human embryonic kidney 293T cells with and without activation. Starting from more than 2,000 captured proteins 30 potential STAT1 interaction partners were extracted. Interestingly, more than 50% of these were already reported or predicted to bind STAT1. Furthermore, 16 proteins were found to affect the binding behavior depending on STAT1 phosphorylation such as STAT3 or the importin subunits alpha 1 and alpha 6.

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Affinity Purification of NF1 Protein–Protein Interactors Identifies Keratins and Neurofibromin Itself as Binding Partners

Genes ◽

10.3390/genes10090650 ◽

2019 ◽

Vol 10 (9) ◽

pp. 650 ◽

Cited By ~ 4

Author(s):

Rachel M. Carnes ◽

Robert A. Kesterson ◽

Bruce R. Korf ◽

James A. Mobley ◽

Deeann Wallis

Keyword(s):

Protein Interactions ◽

Drug Targets ◽

Affinity Purification ◽

Neurofibromatosis Type ◽

Hek293 Cells ◽

Ras Signaling ◽

Affinity Tag ◽

Pathogenic Variants ◽

Binding Partners ◽

Keratin Expression

Neurofibromatosis Type 1 (NF1) is caused by pathogenic variants in the NF1 gene encoding neurofibromin. Definition of NF1 protein–protein interactions (PPIs) has been difficult and lacks replication, making it challenging to define binding partners that modulate its function. We created a novel tandem affinity purification (TAP) tag cloned in frame to the 3’ end of the full-length murine Nf1 cDNA (mNf1). We show that this cDNA is functional and expresses neurofibromin, His-Tag, and can correct p-ERK/ERK ratios in NF1 null HEK293 cells. We used this affinity tag to purify binding partners with Strep-Tactin®XT beads and subsequently, identified them via mass spectrometry (MS). We found the tagged mNf1 can affinity purify human neurofibromin and vice versa, indicating that neurofibromin oligomerizes. We identify 21 additional proteins with high confidence of interaction with neurofibromin. After Metacore network analysis of these 21 proteins, eight appear within the same network, primarily keratins regulated by estrogen receptors. Previously, we have shown that neurofibromin levels negatively regulate keratin expression. Here, we show through pharmacological inhibition that this is independent of Ras signaling, as the inhibitors, selumetinib and rapamycin, do not alter keratin expression. Further characterization of neurofibromin oligomerization and binding partners could aid in discovering new neurofibromin functions outside of Ras regulation, leading to novel drug targets.

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Characterization of a Replicating Mammalian Orthoreovirus with Tetracysteine-Tagged μNS for Live-Cell Visualization of Viral Factories

Journal of Virology ◽

10.1128/jvi.01371-17 ◽

2017 ◽

Vol 91 (22) ◽

Cited By ~ 9

Author(s):

Luke D. Bussiere ◽

Promisree Choudhury ◽

Bryan Bellaire ◽

Cathy L. Miller

Keyword(s):

Nonstructural Protein ◽

Critical Role ◽

Viral Proteins ◽

Live Cell ◽

Host Cells ◽

Live Cells ◽

Virus Protein ◽

Mammalian Orthoreovirus ◽

Virus Proteins

ABSTRACT Within infected host cells, mammalian orthoreovirus (MRV) forms viral factories (VFs), which are sites of viral transcription, translation, assembly, and replication. The MRV nonstructural protein μNS comprises the structural matrix of VFs and is involved in recruiting other viral proteins to VF structures. Previous attempts have been made to visualize VF dynamics in live cells, but due to current limitations in recovery of replicating reoviruses carrying large fluorescent protein tags, researchers have been unable to directly assess VF dynamics from virus-produced μNS. We set out to develop a method to overcome this obstacle by utilizing the 6-amino-acid (CCPGCC) tetracysteine (TC) tag and FlAsH-EDT2 reagent. The TC tag was introduced into eight sites throughout μNS, and the capacity of the TC-μNS fusion proteins to form virus factory-like (VFL) structures and colocalize with virus proteins was characterized. Insertion of the TC tag interfered with recombinant virus rescue in six of the eight mutants, likely as a result of loss of VF formation or important virus protein interactions. However, two recombinant (r)TC-μNS viruses were rescued and VF formation, colocalization with associating virus proteins, and characterization of virus replication were subsequently examined. Furthermore, the rTC-μNS viruses were utilized to infect cells and examine VF dynamics using live-cell microscopy. These experiments demonstrate active VF movement with fusion events as well as transient interactions between individual VFs and demonstrate the importance of microtubule stability for VF fusion during MRV infection. This work provides important groundwork for future in-depth studies of VF dynamics and host cell interactions. IMPORTANCE MRV has historically been used as a model to study the double-stranded RNA (dsRNA) Reoviridae family, the members of which infect and cause disease in humans, animals, and plants. During infection, MRV forms VFs that play a critical role in virus infection but remain to be fully characterized. To study VFs, researchers have focused on visualizing the nonstructural protein μNS, which forms the VF matrix. This work provides the first evidence of recovery of replicating reoviruses in which VFs can be labeled in live cells via introduction of a TC tag into the μNS open reading frame. Characterization of each recombinant reovirus sheds light on μNS interactions with viral proteins. Moreover, utilizing the TC-labeling FlAsH-EDT2 biarsenical reagent to visualize VFs, evidence is provided of dynamic VF movement and interactions at least partially dependent on intact microtubules.

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Subcellular localization of nucleocapsid protein of SFTSV and its assembly into the ribonucleoprotein complex with L protein and viral RNA

Scientific Reports ◽

10.1038/s41598-021-01985-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sithumini M. W. Lokupathirage ◽

Yoshimi Tsuda ◽

Kodai Ikegame ◽

Kisho Noda ◽

Devinda S. Muthusinghe ◽

...

Keyword(s):

Golgi Apparatus ◽

Subcellular Localization ◽

Critical Role ◽

Viral Proteins ◽

Viral Rna ◽

Host Cells ◽

N Protein ◽

L Protein ◽

Translational Activity ◽

Antiviral Targets

AbstractSevere fever with thrombocytopenia syndrome virus (SFTSV) is an emerging bunyavirus that causes novel zoonotic diseases in Asian countries including China, Japan, South Korea, and Vietnam. In phleboviruses, viral proteins play a critical role in viral particle formation inside the host cells. Viral glycoproteins (GPs) and RNA-dependent RNA polymerase (RdRp) are colocalized in the Golgi apparatus and endoplasmic reticulum-Golgi intermediate compartment (ERGIC). The nucleocapsid (N) protein was widely expressed in the cytoplasm, even in cells coexpressing GP. However, the role of SFTSV N protein remains unclear. The subcellular localization of SFTSV structural proteins was investigated using a confocal microscope. Subsequently, minigenome and immunoprecipitation assays were carried out. The N protein interacts with viral RNA (vRNA) and further shows translational activity with RdRp which is L protein and localized in the ERGIC and Golgi apparatus when co-expressed with GP. On the other hand, mutant N protein did not interact with vRNA either localized in the ERGIC or Golgi apparatus. The interaction between the N protein of SFTSV and vRNA is important for the localization of viral proteins and viral assembly. This study provides useful insights into the life cycle of SFTSV, which will lead to the detection of antiviral targets.

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