PLoS PathogensPub Date : 2025-04-08DOI: 10.1371/journal.ppat.1013053
Joëlle Paolo Mesén-Ramírez, Gwendolin Fuchs, Jonas Burmester, Guilherme B Farias, Ana María Alape-Flores, Shamit Singla, Arne Alder, José Cubillán-Marín, Carolina Castro-Peña, Sarah Lemcke, Holger Sondermann, Mónica Prado, Tobias Spielmann, Danny Wilson, Tim-Wolf Gilberger
{"title":"HOPS/CORVET tethering complexes are critical for endocytosis and protein trafficking to invasion related organelles in malaria parasites.","authors":"Joëlle Paolo Mesén-Ramírez, Gwendolin Fuchs, Jonas Burmester, Guilherme B Farias, Ana María Alape-Flores, Shamit Singla, Arne Alder, José Cubillán-Marín, Carolina Castro-Peña, Sarah Lemcke, Holger Sondermann, Mónica Prado, Tobias Spielmann, Danny Wilson, Tim-Wolf Gilberger","doi":"10.1371/journal.ppat.1013053","DOIUrl":"https://doi.org/10.1371/journal.ppat.1013053","url":null,"abstract":"<p><p>The tethering complexes HOPS/CORVET are central for vesicular fusion through the eukaryotic endolysosomal system, but the functions of these complexes in the intracellular development of malaria parasites are still unknown. Here we show that the HOPS/CORVET core subunits are critical for the intracellular proliferation of the malaria parasite Plasmodium falciparum. We demonstrate that HOPS/CORVET are required for parasite endocytosis and host cell cytosol uptake, as early functional depletion of the complex led to developmental arrest and accumulation of endosomes that failed to fuse to the digestive vacuole membrane. Late depletion of the core HOPS/CORVET subunits led to a severe defect in merozoite invasion as a result of the mistargeting of proteins destined to the apical secretory organelles, the rhoptries and micronemes. Ultrastructure-expansion microscopy revealed a reduced rhoptry volume and the accumulation of numerous vesicles in HOPS/CORVET deficient schizonts, further supporting a role of HOPS/CORVET in post-Golgi protein cargo trafficking to the invasion related organelles. Hence, malaria parasites have repurposed HOPS/CORVET to perform dual functions across the intraerythrocytic cycle, consistent with a canonical endocytic pathway for delivery of host cell material to the digestive vacuole in trophozoite stages and a parasite specific role in trafficking of protein cargo to the apical organelles required for invasion in schizont stages.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1013053"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Identification of the Pseudomonas aeruginosa AgtR-CspC-RsaL pathway that controls Las quorum sensing in response to metabolic perturbation and Staphylococcus aureus.","authors":"Junze Qu, Liwen Yin, Shanhua Qin, Xiaomeng Sun, Xuetao Gong, Shouyi Li, Xiaolei Pan, Yongxin Jin, Zhihui Cheng, Shouguang Jin, Weihui Wu","doi":"10.1371/journal.ppat.1013054","DOIUrl":"https://doi.org/10.1371/journal.ppat.1013054","url":null,"abstract":"<p><p>Environmental metabolites and metabolic pathways significantly influence bacterial pathogenesis and interspecies competition. We previously discovered that a mutation in the triosephosphate isomerase gene, tpiA, in Pseudomonas aeruginosa led to defective type III secretion and increased susceptibility to aminoglycoside antibiotics. In this study, we found that the tpiA mutation enhances the Las quorum sensing system due to reduced translation of the negative regulator RsaL. Further investigations demonstrated an upregulation of CspC, a CspA family protein that represses rsaL translation. DNA pull-down assay, along with genetic studies, revealed the role of AgtR in regulating cspC transcription. AgtR is known to regulate pyocyanin production in response to N-acetylglucosamine (GlcNAc), contributing to competition against Staphylococcus aureus. We demonstrated that CspC activates the Las quorum sensing system and subsequent pyocyanin production in response to GlcNAc and S. aureus. Overall, our results elucidate the AgtR-CspC-RsaL-LasI pathway that regulates bacterial virulence factors and its role in competition against S. aureus.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1013054"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"N6-methyladenosine modification of the subgroup J avian leukosis viral RNAs attenuates host innate immunity via MDA5 signaling.","authors":"Mengmeng Yu, Li Zhang, Ying Wang, Suyan Wang, Yongzhen Liu, Peng Liu, Yuntong Chen, Ru Guo, Lingzhai Meng, Tao Zhang, Wenrui Fan, Xiaole Qi, Yulu Duan, Yanping Zhang, Hongyu Cui, Yulong Gao","doi":"10.1371/journal.ppat.1013064","DOIUrl":"https://doi.org/10.1371/journal.ppat.1013064","url":null,"abstract":"<p><p>Subgroup J avian leukosis virus (ALV-J), a retrovirus, elicits immunosuppression and persistent infections in chickens. Although it is widely acknowledged that ALV-J can evade the host's innate immune defenses, the mechanisms behind this immune evasion remain elusive. N6-methyladenosine (m6A), the most prevalent internal RNA modification, plays a role in innate immune evasion. Our research identified ALV-J as an inefficient stimulator of innate immunity in vitro and in vivo, with its genomic RNA featuring m6A modifications predominantly in the envelope protein (Env) region and 3' untranslated region (3'UTR). To elucidate the functional consequences of m6A modification, we subsequently generated m6A-deficient ALV-J through its culturing in the DF-1 overexpressing fat mass and obesity-associated protein (FTO) cells. The m6A-deficient ALV-J virus, or its RNAs significantly enhanced IFN-β production compared to the wild-type (wt) ALV-J, suggesting a pivotal regulatory function of m6A modifications in modulating innate immune response. Mechanistically, the m6A modification of the ALV-J genomic RNA directly impacted its recognition by MDA5, weakening its binding and ubiquitination and attenuating IFN-β activation. Moreover, m6A-deficient ALV-J, created by inducing mutations in m6A sites within Env and 3'UTR, exhibited reduced replication capacity and elevated IFN-β expression in host cells. Importantly, this phenomenon was abolished in MDA5-knockout DF-1 cells, further demonstrating the core role of MDA5. These data demonstrate that m6A modification of ALV-J genomic RNA dampens the host's innate immune response through MDA5 signaling pathway.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1013064"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143812355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PLoS PathogensPub Date : 2025-04-08DOI: 10.1371/journal.ppat.1012452
Adwait Parchure, Mia Cesarec, Antonija Braut, Robert Kolman, Vlatka Ivanišević, Marina Čunko, Slađana Bursać, Richard de Reuver, Antonija J Begonja, Umberto Rosani, Siniša Volarević, Jonathan Maelfait, Igor Jurak
{"title":"ADAR1 p150 prevents HSV-1 from triggering PKR/eIF2α-mediated translational arrest and is required for efficient viral replication.","authors":"Adwait Parchure, Mia Cesarec, Antonija Braut, Robert Kolman, Vlatka Ivanišević, Marina Čunko, Slađana Bursać, Richard de Reuver, Antonija J Begonja, Umberto Rosani, Siniša Volarević, Jonathan Maelfait, Igor Jurak","doi":"10.1371/journal.ppat.1012452","DOIUrl":"https://doi.org/10.1371/journal.ppat.1012452","url":null,"abstract":"<p><p>Adenosine deaminase acting on dsRNA 1 (ADAR1) catalyzes the deamination of adenosines to inosines in double-stranded RNAs (dsRNA) and regulates innate immunity by preventing the hyperactivation of cytosolic dsRNA sensors such as MDA5, PKR or ZBP1. ADAR1 has been shown to exert pro- and antiviral, editing-dependent and editing-independent functions in viral infections, but little is known about its function in herpesvirus replication. We now demonstrate that herpes simplex virus 1 (HSV-1) hyperactivates PKR in the absence of ADAR1, resulting in eIF2α mediated translational arrest and reduced viral replication. Silencing of PKR or inhibition of its downstream effectors by viral (ICP34.5) or pharmacological (ISRIB) inhibitors rescues viral replication in ADAR1-deficient cells. Upon infection, ADAR1 p150 interacts with PKR and prevents its hyperactivation. Our findings demonstrate that ADAR1 is an important proviral factor that raises the activation threshold for sensors of innate immunity.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1012452"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PLoS PathogensPub Date : 2025-04-08DOI: 10.1371/journal.ppat.1012467
Manickam Ashokkumar, Terry L Hafer, Abby Felton, Nancie M Archin, David M Margolis, Michael Emerman, Edward P Browne
{"title":"A targeted CRISPR screen identifies ETS1 as a regulator of HIV-1 latency.","authors":"Manickam Ashokkumar, Terry L Hafer, Abby Felton, Nancie M Archin, David M Margolis, Michael Emerman, Edward P Browne","doi":"10.1371/journal.ppat.1012467","DOIUrl":"https://doi.org/10.1371/journal.ppat.1012467","url":null,"abstract":"<p><p>Human Immunodeficiency virus (HIV) infection is regulated by a wide array of host cell factors that combine to influence viral transcription and latency. To understand the complex relationship between the host cell and HIV-1 latency, we performed a lentiviral CRISPR screen that targeted a set of host cell genes whose expression or activity correlates with HIV-1 expression. We further investigated one of the identified factors - the transcription factor ETS1, and found that it is required for maintenance of HIV-1 latency in both latently infected cell lines and in a primary CD4 T cell latency model. Interestingly, ETS1 played divergent roles in actively infected and latently infected CD4 T cells, with knockout of ETS1 leading to reduced HIV-1 expression in actively infected cells, but increased HIV-1 expression in latently infected cells, indicating that ETS1 can play both a positive and negative role in HIV-1 expression. CRISPR/Cas9 knockout of ETS1 in CD4 T cells from ART-suppressed people with HIV-1 (PWH) confirmed that ETS1 maintains transcriptional repression of the clinical HIV-1 reservoir. Transcriptomic profiling of ETS1-depleted cells from PWH identified a set of host cell pathways involved in viral transcription that are controlled by ETS1 in resting CD4 T cells. In particular, we observed that ETS1 knockout increased expression of the long non-coding RNA MALAT1 that has been previously identified as a positive regulator of HIV-1 expression. Furthermore, the impact of ETS1 depletion on HIV-1 expression in latently infected cells was partially dependent on MALAT1. Additionally, we demonstrate that ETS1 knockout resulted in enhanced abundance of activating modifications (H3K9Ac, H3K27Ac, H3K4me3) on histones located at the HIV-1 long terminal repeat (LTR), indicating that ETS1 regulates the activity of chromatin-targeting complexes at the HIV-1 LTR. Overall, these data demonstrate that ETS1 is an important regulator of HIV-1 latency that impacts HIV-1 expression through repressing MALAT1 expression and by regulating modification of proviral histones.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1012467"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Chlamydial protease-like activity factor targets SLC7A11 for degradation to induce ferroptosis and facilitate progeny releases.","authors":"Wentao Chen, Xin Su, Yuying Pan, Han Zhou, Yidan Gao, Xuemei Wang, Lijuan Jiang, Lihong Zeng, Qingqing Xu, Xueying Yu, Xiaona Yin, Zhanqin Feng, Bao Zhang, Wei Zhao, Yaohua Xue, Lingli Tang, Heping Zheng","doi":"10.1371/journal.ppat.1013060","DOIUrl":"https://doi.org/10.1371/journal.ppat.1013060","url":null,"abstract":"<p><p>Chlamydia trachomatis, the most prevalent bacterial agent of sexually transmitted infections, poses a significant threat to reproductive health. The release of progeny through the orchestrated lysis of host cells plays a crucial role for the development of new infections, though the underlying molecular mechanisms remaining largely unexplored. In this study, we identified a novel mechanism by which Chlamydia induces host cell ferroptosis to facilitate its progeny release. This process involves the degradation of the host protein SLC7A11 by the chlamydial protease-like activity factor (CPAF), resulting in glutathione depletion and subsequent cell death characterized by lipid peroxidation. Infection with a CPAF-deficient strain fails to induce host cell ferroptosis. Notably, inhibiting ferroptosis by vitamin E reduces the Chlamydia burden in low genital tract of mice and trends toward attenuation of pathology. These findings provide new insights into the conserved survival strategies of Chlamydia and understanding of its pathogenesis.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1013060"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PLoS PathogensPub Date : 2025-04-08DOI: 10.1371/journal.ppat.1012808
Sabrina Lusvarghi, Russell Vassell, Brittany Williams, Haseebullah Baha, Sabari Nath Neerukonda, Carol D Weiss
{"title":"Capture of fusion-intermediate conformations of SARS-CoV-2 spike requires receptor binding and cleavage at either the S1/S2 or S2' site.","authors":"Sabrina Lusvarghi, Russell Vassell, Brittany Williams, Haseebullah Baha, Sabari Nath Neerukonda, Carol D Weiss","doi":"10.1371/journal.ppat.1012808","DOIUrl":"https://doi.org/10.1371/journal.ppat.1012808","url":null,"abstract":"<p><p>Although structures of pre- and post-fusion conformations of SARS-CoV-2 spikes have been solved by cryo-electron microscopy, the transient spike conformations that mediate virus fusion with host cell membranes remain poorly understood. In this study, we used a peptide fusion inhibitor corresponding to the heptad repeat 2 (HR2) in the S2 transmembrane subunit of the spike to investigate fusion-intermediate conformations that involve exposure of the highly conserved heptad repeat 1 (HR1). The HR2 peptide disrupts the assembly of the HR1 and HR2 regions of the spike, which form a six-helix bundle during the transition to the post-fusion conformation. We show that binding of the spike S1 subunit to ACE2 is sufficient to induce conformational changes that allow S1 shedding and enable the HR2 peptide to bind to fusion-intermediate conformations of S2 and inhibit membrane fusion. When TMPRSS2 is also present, the peptide captures an S2' fusion intermediate though the proportion of the S2' intermediate relative to the S2 intermediate is lower in Omicron variants than pre-Omicron variants. In spikes lacking the natural S1/S2 furin cleavage site, ACE2 binding alone is not sufficient for trapping fusion intermediates, but the presence of ACE2 and TMPRSS2 allows peptide trapping of an S2' intermediate. These results indicate that, in addition to ACE2 engagement, at least one spike cleavage is needed for unwinding S2 into an HR2 peptide-sensitive, fusion-intermediate conformation. Our findings elucidate fusion-intermediate conformations of SARS-CoV-2 spike variants that expose conserved sites on spike that could be targeted by inhibitors or antibodies.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1012808"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PLoS PathogensPub Date : 2025-04-08eCollection Date: 2025-04-01DOI: 10.1371/journal.ppat.1013015
Xuan Dong, Fan Zhang, Yiting Wang, Cixiu Li, Xuan Li, Chengyan Zhou, Guohao Wang, Zhongshuai Tian, Jing Gao, Hu Zhou, Liying Sui, Hans Nauwynck, Patrick Sorgeloos, Edward C Holmes, Jie Huang, Weifeng Shi
{"title":"A positive-sense single-stranded RNA virus acquired a negative-sense open reading frame through recombination.","authors":"Xuan Dong, Fan Zhang, Yiting Wang, Cixiu Li, Xuan Li, Chengyan Zhou, Guohao Wang, Zhongshuai Tian, Jing Gao, Hu Zhou, Liying Sui, Hans Nauwynck, Patrick Sorgeloos, Edward C Holmes, Jie Huang, Weifeng Shi","doi":"10.1371/journal.ppat.1013015","DOIUrl":"https://doi.org/10.1371/journal.ppat.1013015","url":null,"abstract":"<p><p>Although positive- and negative-sense single-stranded RNA viruses are ubiquitous in nature, there is currently no evidence of recombination or reassortment between viruses with these two major forms of genome organization. Here, we describe the discovery of brine shrimp virga-like virus 1 (BSVV1), a novel positive-sense single-stranded RNA virus with a recombinant genome structure derived from two viral phyla with differing genome organizations. The genome of BSVV1 comprises three open reading frames (ORFs). ORF1 resembles the RNA-dependent RNA polymerase of Ips virga-like virus 1 (a positive-sense RNA virus), while ORF2, transcribed in the positive orientation, is related to the glycoprotein of Hubei bunya-like virus 10 and other negative-sense RNA viruses. The predicted ORF3 was unique to BSVV1 without known homologs identified. The presence of the three protein products was verified by mass spectrometry. Notably, our analysis also revealed that BSVV1 is geographically widespread and found in brine shrimp from at least eight countries on four continents. In addition, BSVV1 was successfully cultured and proliferated to high viral loads during brine shrimp development. In sum, we provide compelling evidence of an ancient recombination event between negative- and positive-sense single-stranded RNA viruses, enriching our understanding of the evolution of genome structures in RNA viruses.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1013015"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143812743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PLoS PathogensPub Date : 2025-04-08eCollection Date: 2025-04-01DOI: 10.1371/journal.ppat.1012971
Julie Le Bris, Nathalie Chen, Adeline Supandy, Olaya Rendueles, Daria Van Tyne
{"title":"Phage therapy for Klebsiella pneumoniae: Understanding bacteria-phage interactions for therapeutic innovations.","authors":"Julie Le Bris, Nathalie Chen, Adeline Supandy, Olaya Rendueles, Daria Van Tyne","doi":"10.1371/journal.ppat.1012971","DOIUrl":"https://doi.org/10.1371/journal.ppat.1012971","url":null,"abstract":"<p><p>Klebsiella pneumoniae (KP) is a Gram-negative bacterium that commonly resides in the human gastrointestinal tract and can also act as an opportunistic pathogen and cause extra-intestinal infections. KP poses a global health threat because it causes both hospital- and community-acquired infections in immune-competent and immunocompromised hosts. These infections can be multidrug-resistant and/or hypervirulent, making KP infections difficult to treat and deadly. In the absence of effective treatments for recalcitrant KP infections, bacteriophage (phage) therapy is gaining attention as a promising alternative. In this review, we evaluate KP epidemiology and epitope diversity, discuss interactions between KP-targeting phages and their bacterial hosts from an eco-evolutionary perspective, and summarize recent efforts in phage therapy for treating KP infections. We also discuss novel approaches, including genetic engineering and machine learning, as initial steps toward developing KP-targeting phage therapy as a precision medicine approach for an emerging and dangerous pathogen.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1012971"},"PeriodicalIF":5.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143812359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PLoS PathogensPub Date : 2025-04-07DOI: 10.1371/journal.ppat.1013050
Aditya Thiruvaiyaru, Sari Mattila, Mohammadreza Sadeghi, Krystyna Naumenko, Andres Merits, Markku Varjosalo, Tero Ahola
{"title":"Proximity interactome of alphavirus replicase component nsP3 includes proviral host factors eIF4G and AHNAK.","authors":"Aditya Thiruvaiyaru, Sari Mattila, Mohammadreza Sadeghi, Krystyna Naumenko, Andres Merits, Markku Varjosalo, Tero Ahola","doi":"10.1371/journal.ppat.1013050","DOIUrl":"https://doi.org/10.1371/journal.ppat.1013050","url":null,"abstract":"<p><p>All positive-strand RNA viruses replicate their genomes in association with modified intracellular membranes, inducing either membrane invaginations termed spherules, or double-membrane vesicles. Alphaviruses encode four non-structural proteins nsP1-nsP4, all of which are essential for RNA replication and spherule formation. To understand the host factors associated with the replication complex, we fused the efficient biotin ligase miniTurbo with Semliki Forest virus (SFV) nsP3, which is located on the cytoplasmic surface of the spherules. We characterized the proximal proteome of nsP3 in three cell lines, including cells unable to form stress granules, and identified >300 host proteins constituting the microenvironment of nsP3. These included all the nsPs, as well as several previously characterized nsP3 binding proteins. However, the majority of the identified interactors had no previously identified roles in alphavirus replication, including 39 of the top 50 interacting proteins. The most prominent biological processes involving the proximal proteins were nucleic acid metabolism, translational regulation, cytoskeletal rearrangement and membrane remodeling. siRNA silencing confirmed six novel proviral factors, USP10, AHNAK, eIF4G1, SH3GL1, XAB2 and ANKRD17, which are associated with distinct cellular functions. All of these except SH3GL1 were also important for the replication of chikungunya virus. We discovered that the small molecule 4E1RCat, which inhibits the interaction between the canonical translation initiation factors eIF4G and eIF4E, exhibits antiviral activity against SFV. Since the same molecule was previously found to inhibit coronaviruses, this suggest the possibility that translation initiation factors could be considered as targets for broadly acting antivirals.</p>","PeriodicalId":48999,"journal":{"name":"PLoS Pathogens","volume":"21 4","pages":"e1013050"},"PeriodicalIF":5.5,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143804664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}