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He J, Yu Y, Liu W, Li Z, Qi Z, Weng S, Guo C, He J. Molecular mechanism of infectious spleen and kidney necrosis virus in manipulating the hypoxia-inducible factor pathway to augment virus replication. Virulence 2024; 15:2349027. [PMID: 38680083 PMCID: PMC11085990 DOI: 10.1080/21505594.2024.2349027] [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: 01/08/2024] [Accepted: 03/28/2024] [Indexed: 05/01/2024] Open
Abstract
Infectious spleen and kidney necrosis virus (ISKNV), a member of the genus Megalocytivirus in the family Iridoviridae, can infect over 50 fish species and cause significant economic losses in Asia. Our previous study showed that hypoxia triggers the hypoxia-inducible factor pathway (HIF-pathway), leading to increased replication of ISKNV through promoting the upregulation of viral hypoxic response genes like orf077r. This study delved into the molecular mechanism of how ISKNV manipulates the HIF-pathway to enhance its replication. In vitro and in vivo experiments confirmed that ISKNV infection activated the HIF-pathway, which in turn promoted ISKNV replication. These findings suggest that ISKNV actively manipulates the HIF-pathway. Co-immunoprecipitation experiments revealed that the ISKNV-encoded protein VP077R interacts with the Von Hippel-Lindau (VHL) protein at the HIF-binding region, competitively inhibiting the interaction of HIF-1α with VHL. This prevents HIF degradation and activates the HIF-pathway. Furthermore, VP077R interacts with factor-inhibiting HIF (FIH), recruiting FIH and S-phase kinase-associated protein 1 (Skp1) to form an FIH - VP077R - Skp1 complex. This complex promotes FIH protein degradation via ubiquitination, further activating the HIF-pathway. These findings indicated that ISKNV takes over the HIF-pathway by releasing two "brakes" on this pathway (VHL and FIH) via VP077R, facilitating virus replication. We speculate that hypoxia initiates a positive feedback loop between ISKNV VP077R and the HIF pathway, leading to the outbreak of ISKNV disease. This work offers valuable insights into the complex interactions between the environment, host, and virus.
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Affiliation(s)
- Jian He
- State Key Laboratory for Biocontrol/Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Guangdong Provincial Observation and Research Station for Marine Ranching of the Lingdingyang Bay, School of Marine Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Yang Yu
- State Key Laboratory for Biocontrol/Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Guangdong Provincial Observation and Research Station for Marine Ranching of the Lingdingyang Bay, School of Marine Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Wenhui Liu
- State Key Laboratory for Biocontrol/Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Guangdong Provincial Observation and Research Station for Marine Ranching of the Lingdingyang Bay, School of Marine Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Zhimin Li
- State Key Laboratory for Biocontrol/Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Guangdong Provincial Observation and Research Station for Marine Ranching of the Lingdingyang Bay, School of Marine Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Zhang Qi
- State Key Laboratory for Biocontrol/Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Guangdong Provincial Observation and Research Station for Marine Ranching of the Lingdingyang Bay, School of Marine Sciences, Sun Yat-sen University, Guangzhou, PR China
| | - Shaoping Weng
- Guangdong Province Key Laboratory of Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China
| | - Changjun Guo
- State Key Laboratory for Biocontrol/Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Guangdong Provincial Observation and Research Station for Marine Ranching of the Lingdingyang Bay, School of Marine Sciences, Sun Yat-sen University, Guangzhou, PR China
- Guangdong Province Key Laboratory of Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China
| | - Jianguo He
- State Key Laboratory for Biocontrol/Southern Laboratory of Ocean Science and Engineering (Guangdong, Zhuhai), Guangdong Provincial Observation and Research Station for Marine Ranching of the Lingdingyang Bay, School of Marine Sciences, Sun Yat-sen University, Guangzhou, PR China
- Guangdong Province Key Laboratory of Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China
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Nelson DR, Hazzouri KM, Lauersen KJ, Jaiswal A, Chaiboonchoe A, Mystikou A, Fu W, Daakour S, Dohai B, Alzahmi A, Nobles D, Hurd M, Sexton J, Preston MJ, Blanchette J, Lomas MW, Amiri KMA, Salehi-Ashtiani K. Large-scale genome sequencing reveals the driving forces of viruses in microalgal evolution. Cell Host Microbe 2021; 29:250-266.e8. [PMID: 33434515 DOI: 10.1016/j.chom.2020.12.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/08/2020] [Accepted: 11/18/2020] [Indexed: 01/08/2023]
Abstract
Being integral primary producers in diverse ecosystems, microalgal genomes could be mined for ecological insights, but representative genome sequences are lacking for many phyla. We cultured and sequenced 107 microalgae species from 11 different phyla indigenous to varied geographies and climates. This collection was used to resolve genomic differences between saltwater and freshwater microalgae. Freshwater species showed domain-centric ontology enrichment for nuclear and nuclear membrane functions, while saltwater species were enriched in organellar and cellular membrane functions. Further, marine species contained significantly more viral families in their genomes (p = 8e-4). Sequences from Chlorovirus, Coccolithovirus, Pandoravirus, Marseillevirus, Tupanvirus, and other viruses were found integrated into the genomes of algal from marine environments. These viral-origin sequences were found to be expressed and code for a wide variety of functions. Together, this study comprehensively defines the expanse of protein-coding and viral elements in microalgal genomes and posits a unified adaptive strategy for algal halotolerance.
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Affiliation(s)
- David R Nelson
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE.
| | - Khaled M Hazzouri
- Khalifa Center for Genetic Engineering and Biotechnology (KCGEB), UAE University, Al Ain, Abu Dhabi, UAE; Biology Department, College of Science, UAE University, Al Ain, Abu Dhabi, UAE
| | - Kyle J Lauersen
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Ashish Jaiswal
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | | | - Alexandra Mystikou
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Weiqi Fu
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Sarah Daakour
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Bushra Dohai
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Amnah Alzahmi
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - David Nobles
- UTEX Culture Collection of Algae at the University of Texas at Austin, Austin, TX, USA
| | - Mark Hurd
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Julie Sexton
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Michael J Preston
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Joan Blanchette
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Michael W Lomas
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Khaled M A Amiri
- Khalifa Center for Genetic Engineering and Biotechnology (KCGEB), UAE University, Al Ain, Abu Dhabi, UAE; Biology Department, College of Science, UAE University, Al Ain, Abu Dhabi, UAE
| | - Kourosh Salehi-Ashtiani
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE; Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE.
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Van Etten JL, Agarkova IV, Dunigan DD. Chloroviruses. Viruses 2019; 12:E20. [PMID: 31878033 PMCID: PMC7019647 DOI: 10.3390/v12010020] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/13/2019] [Accepted: 12/15/2019] [Indexed: 12/20/2022] Open
Abstract
Chloroviruses are large dsDNA, plaque-forming viruses that infect certain chlorella-like green algae; the algae are normally mutualistic endosymbionts of protists and metazoans and are often referred to as zoochlorellae. The viruses are ubiquitous in inland aqueous environments throughout the world and occasionally single types reach titers of thousands of plaque-forming units per ml of native water. The viruses are icosahedral in shape with a spike structure located at one of the vertices. They contain an internal membrane that is required for infectivity. The viral genomes are 290 to 370 kb in size, which encode up to 16 tRNAs and 330 to ~415 proteins, including many not previously seen in viruses. Examples include genes encoding DNA restriction and modification enzymes, hyaluronan and chitin biosynthetic enzymes, polyamine biosynthetic enzymes, ion channel and transport proteins, and enzymes involved in the glycan synthesis of the virus major capsid glycoproteins. The proteins encoded by many of these viruses are often the smallest or among the smallest proteins of their class. Consequently, some of the viral proteins are the subject of intensive biochemical and structural investigation.
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Affiliation(s)
- James L. Van Etten
- Department of Plant Pathology, Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583-0900, USA; (I.V.A.); (D.D.D.)
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de Macêdo Mendes C, Teixeira DG, Lima JPMS, Lanza DCF. Characterization of putative proteins encoded by variable ORFs in white spot syndrome virus genome. BMC STRUCTURAL BIOLOGY 2019; 19:8. [PMID: 30999895 PMCID: PMC6474068 DOI: 10.1186/s12900-019-0106-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 03/28/2019] [Indexed: 01/07/2023]
Abstract
Background White Spot Syndrome Virus (WSSV) is an enveloped double-stranded DNA virus which causes mortality of several species of shrimp, being considered one of the main pathogens that affects global shrimp farming. This virus presents a complex genome of ~ 300 kb and viral isolates that present genomes with great identity. Despite this conservation, some variable regions in the WSSV genome occur in coding regions, and these putative proteins may have some relationship with viral adaptation and virulence mechanisms. Until now, the functions of these proteins were little studied. In this work, sequences and putative proteins encoded by WSSV variable regions were characterized in silico. Results The in silico approach enabled determining the variability of some sequences, as well as the identification of some domains resembling the Formin homology 2, RNA recognition motif, Xeroderma pigmentosum group D repair helicase, Hemagglutinin and Ankyrin motif. The information obtained from the sequences and the analysis of secondary and tertiary structure models allow to infer that some of these proteins possibly have functions related to protein modulation/degradation, intracellular transport, recombination and endosome fusion events. Conclusions The bioinformatics approaches were efficient in generating three-dimensional models and to identify domains, thereby enabling to propose possible functions for the putative polypeptides produced by the ORFs wsv129, wsv178, wsv249, wsv463a, wsv477, wsv479, wsv492, and wsv497. Electronic supplementary material The online version of this article (10.1186/s12900-019-0106-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Cayro de Macêdo Mendes
- Applied Molecular Biology Lab - LAPLIC, Department of Biochemistry, Federal University of Rio Grande do Norte, Natal, RN, Brazil.,Postgraduate Program in Bioinformatics, Federal University of Rio Grande do Norte, Natal, RN, Brazil
| | - Diego Gomes Teixeira
- Postgraduate Program in Biochemistry, Federal University of Rio Grande do Norte, Natal, RN, Brazil
| | - João Paulo Matos Santos Lima
- Postgraduate Program in Bioinformatics, Federal University of Rio Grande do Norte, Natal, RN, Brazil.,Postgraduate Program in Biochemistry, Federal University of Rio Grande do Norte, Natal, RN, Brazil
| | - Daniel Carlos Ferreira Lanza
- Applied Molecular Biology Lab - LAPLIC, Department of Biochemistry, Federal University of Rio Grande do Norte, Natal, RN, Brazil. .,Postgraduate Program in Bioinformatics, Federal University of Rio Grande do Norte, Natal, RN, Brazil. .,Postgraduate Program in Biochemistry, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
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Evans SM, Rodino KG, Adcox HE, Carlyon JA. Orientia tsutsugamushi uses two Ank effectors to modulate NF-κB p65 nuclear transport and inhibit NF-κB transcriptional activation. PLoS Pathog 2018; 14:e1007023. [PMID: 29734393 PMCID: PMC5957444 DOI: 10.1371/journal.ppat.1007023] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 05/17/2018] [Accepted: 04/11/2018] [Indexed: 01/05/2023] Open
Abstract
Orientia tsutsugamushi causes scrub typhus, a potentially fatal infection that threatens over one billion people. Nuclear translocation of the transcription factor, NF-κB, is the central initiating cellular event in the antimicrobial response. Here, we report that NF-κB p65 nuclear accumulation and NF-κB-dependent transcription are inhibited in O. tsutsugamushi infected HeLa cells and/or primary macrophages, even in the presence of TNFα. The bacterium modulates p65 subcellular localization by neither degrading it nor inhibiting IκBα degradation. Rather, it exploits host exportin 1 to mediate p65 nuclear export, as this phenomenon is leptomycin B-sensitive. O. tsutsugamushi antagonizes NF-κB-activated transcription even when exportin 1 is inhibited and NF-κB consequently remains in the nucleus. Two ankyrin repeat-containing effectors (Anks), Ank1 and Ank6, each of which possess a C-terminal F-box and exhibit 58.5% amino acid identity, are linked to the pathogen's ability to modulate NF-κB. When ectopically expressed, both translocate to the nucleus, abrogate NF-κB-activated transcription in an exportin 1-independent manner, and pronouncedly reduce TNFα-induced p65 nuclear levels by exportin 1-dependent means. Flag-tagged Ank 1 and Ank6 co-immunoprecipitate p65 and exportin 1. Both also bind importin β1, a host protein that is essential for the classical nuclear import pathway. Importazole, which blocks importin β1 activity, abrogates Ank1 and Ank6 nuclear translocation. The Ank1 and Ank6 regions that bind importin β1 also mediate their transport into the nucleus. Yet, these regions are distinct from those that bind p65/exportin 1. The Ank1 and Ank6 F-box and the region that lies between it and the ankyrin repeat domain are essential for blocking p65 nuclear accumulation. These data reveal a novel mechanism by which O. tsutsugamushi modulates the activity and nuclear transport of NF-κB p65 and identify the first microbial proteins that co-opt both importin β1 and exportin 1 to antagonize a critical arm of the antimicrobial response.
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Affiliation(s)
- Sean M. Evans
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, United States of America
| | - Kyle G. Rodino
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, United States of America
| | - Haley E. Adcox
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, United States of America
| | - Jason A. Carlyon
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, United States of America
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Kariithi HM, Meki IK, Boucias DG, Abd-Alla AM. Hytrosaviruses: current status and perspective. CURRENT OPINION IN INSECT SCIENCE 2017; 22:71-78. [PMID: 28805642 DOI: 10.1016/j.cois.2017.05.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Accepted: 05/01/2017] [Indexed: 06/07/2023]
Abstract
Salivary gland hytrosaviruses (SGHVs) are entomopathogenic dsDNA, enveloped viruses that replicate in the salivary glands (SGs) of the adult dipterans, Glossina spp (GpSGHV) and Musca domestica (MdSGHV). Although belonging to the same virus family (Hytrosaviridae), SGHVs have distinct morphologies and pathobiologies. Two GpSGHV strains potentially account for the differential pathologies in lab-bred tsetse. New data suggest incorporation of host-derived cellular proteins and lipids into mature SGHVs. In addition to within the SGs, MdSGHV undergoes limited replication in the corpora allata, potentially disrupting hormone biosynthesis, and GpSGHV replicates in the milk glands providing a transmission conduit to progeny tsetse. Whereas MdSGHV is a potential biocontrol agent, the vertically transmitted GpSGHV is unsuitable for tsetse vector control but does jeopardize tsetse mass rearing.
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Affiliation(s)
- Henry M Kariithi
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food & Agriculture, P.O. Box 100, Wagrammer Straße 5, A-1400 Vienna, Austria
| | - Irene K Meki
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food & Agriculture, P.O. Box 100, Wagrammer Straße 5, A-1400 Vienna, Austria
| | - Drion G Boucias
- Entomology and Nematology Department, University of Florida, 970 Steinmetz Hall, Gainesville, FL 32611, USA
| | - Adly Mm Abd-Alla
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food & Agriculture, P.O. Box 100, Wagrammer Straße 5, A-1400 Vienna, Austria.
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Efficiency in Complexity: Composition and Dynamic Nature of Mimivirus Replication Factories. J Virol 2016; 90:10039-10047. [PMID: 27581975 DOI: 10.1128/jvi.01319-16] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 08/18/2016] [Indexed: 11/20/2022] Open
Abstract
The recent discovery of multiple giant double-stranded DNA (dsDNA) viruses blurred the consensual distinction between viruses and cells due to their size, as well as to their structural and genetic complexity. A dramatic feature revealed by these viruses as well as by many positive-strand RNA viruses is their ability to rapidly form elaborate intracellular organelles, termed "viral factories," where viral progeny are continuously generated. Here we report the first isolation of viral factories at progressive postinfection time points. The isolated factories were subjected to mass spectrometry-based proteomics, bioinformatics, and imaging analyses. These analyses revealed that numerous viral proteins are present in the factories but not in mature virions, thus implying that multiple and diverse proteins are required to promote the efficiency of viral factories as "production lines" of viral progeny. Moreover, our results highlight the dynamic and highly complex nature of viral factories, provide new and general insights into viral infection, and substantiate the intriguing notion that viral factories may represent the living state of viruses. IMPORTANCE Large dsDNA viruses such as vaccinia virus and the giant mimivirus, as well as many positive-strand RNA viruses, generate elaborate cytoplasmic organelles in which the multiple and diverse transactions required for viral replication and assembly occur. These organelles, which were termed "viral factories," are attracting much interest due to the increasing realization that the rapid and continuous production of viral progeny is a direct outcome of the elaborate structure and composition of the factories, which act as efficient production lines. To get new insights into the nature and function of viral factories, we devised a method that allows, for the first time, the isolation of these organelles. Analyses of the isolated factories generated at different times postinfection by mass spectrometry-based proteomics provide new perceptions of their role and reveal the highly dynamic nature of these organelles.
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Orientia tsutsugamushi Strain Ikeda Ankyrin Repeat-Containing Proteins Recruit SCF1 Ubiquitin Ligase Machinery via Poxvirus-Like F-Box Motifs. J Bacteriol 2015; 197:3097-109. [PMID: 26170417 DOI: 10.1128/jb.00276-15] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 07/10/2015] [Indexed: 12/20/2022] Open
Abstract
UNLABELLED A rising theme among intracellular microbes is the delivery of ankyrin repeat-containing effectors (Anks) that interact with target proteins to co-opt host cell functions. Orientia tsutsugamushi, an obligate intracellular bacterium and the etiologic agent of scrub typhus, encodes one of the largest Ank repertoires of any sequenced microorganism. They have been previously identified as type 1 secretion system substrates. Here, in silico and manual sequence analyses revealed that a large proportion of O. tsutsugamushi strain Ikeda Anks bear a eukaryotic/poxvirus-like F-box motif, which is known to recruit host cell SCF1 ubiquitin ligase machinery. We assessed the Anks for the ability to serve as F-box proteins. Coimmunoprecipitation assays demonstrated that F-box-containing Anks interact with overexpressed and/or endogenous SCF1 components. When coexpressed with FLAG-Ank4_01 or FLAG-Ank9, a glutathione S-transferase (GST)-tagged version of the SCF1 component SKP1 localized to subcellular sites of FLAG-Ank accumulation. The abilities of recombinant Anks to interact and colocalize with SKP1 were F-box dependent. GST-SKP1 precipitated O. tsutsugamushi-derived Ank9 from infected host cells, verifying both that the pathogen expresses Ank9 during infection and the protein's capability to bind SKP1. Aligning O. tsutsugamushi, poxviral, and eukaryotic F-box sequences delineated three F-box residues that are highly conserved and likely to be functionally important. Substitution of these residues ablated the ability of GFP-Ank9 to interact with GST-SKP1. These results demonstrate that O. tsutsugamushi strain Ikeda Anks can co-opt host cell polyubiquitination machinery, provide the first evidence that an O. tsutsugamushi Ank does so during infection, and advance overall understanding of microbial F-box proteins. IMPORTANCE Ankyrin repeat-containing proteins (Anks) are important virulence factors of intracellular bacteria that mediate protein-protein interactions with host cell targets. Orientia tsutsugamushi, which causes a debilitating infection called scrub typhus in one of the most densely populated regions of the world, encodes one of the largest Ank armamentariums of any sequenced bacterium. This study demonstrates that O. tsutsugamushi strain Ikeda Anks also bear F-box motifs that interact with host cell polyubiquitination machinery. By proving that an Orientia-derived Ank interacts with SKP1 in infected cells, this evidences the first bona fide Orientia effector and the first example of an endogenous F-box-containing Ank-mammalian-host ligand interaction for any intracellular bacterium. Also, importantly, this work identifies key residues that are essential for microbial F-box function.
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