1
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Miller JR, Koren S, Dilley KA, Puri V, Brown DM, Harkins DM, Thibaud-Nissen F, Rosen B, Chen XG, Tu Z, Sharakhov IV, Sharakhova MV, Sebra R, Stockwell TB, Bergman NH, Sutton GG, Phillippy AM, Piermarini PM, Shabman RS. Analysis of the Aedes albopictus C6/36 genome provides insight into cell line utility for viral propagation. Gigascience 2018; 7:1-13. [PMID: 29329394 PMCID: PMC5869287 DOI: 10.1093/gigascience/gix135] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 12/23/2017] [Indexed: 12/25/2022] Open
Abstract
Background The 50-year-old Aedes albopictus C6/36 cell line is a resource for the detection, amplification, and analysis of mosquito-borne viruses including Zika, dengue, and chikungunya. The cell line is derived from an unknown number of larvae from an unspecified strain of Aedes albopictus mosquitoes. Toward improved utility of the cell line for research in virus transmission, we present an annotated assembly of the C6/36 genome. Results The C6/36 genome assembly has the largest contig N50 (3.3 Mbp) of any mosquito assembly, presents the sequences of both haplotypes for most of the diploid genome, reveals independent null mutations in both alleles of the Dicer locus, and indicates a male-specific genome. Gene annotation was computed with publicly available mosquito transcript sequences. Gene expression data from cell line RNA sequence identified enrichment of growth-related pathways and conspicuous deficiency in aquaporins and inward rectifier K+ channels. As a test of utility, RNA sequence data from Zika-infected cells were mapped to the C6/36 genome and transcriptome assemblies. Host subtraction reduced the data set by 89%, enabling faster characterization of nonhost reads. Conclusions The C6/36 genome sequence and annotation should enable additional uses of the cell line to study arbovirus vector interactions and interventions aimed at restricting the spread of human disease.
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Affiliation(s)
- Jason R Miller
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850, USA.,College of Natural Sciences and Mathematics, Shepherd University, Shepherdstown, WV 25443, USA
| | - Sergey Koren
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, Bethesda, MD 20892, USA
| | - Kari A Dilley
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850, USA
| | - Vinita Puri
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850, USA
| | - David M Brown
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850, USA
| | - Derek M Harkins
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850, USA
| | | | - Benjamin Rosen
- USDA 10300 Baltimore Ave., Bldg 306 Barc-East, Beltsville, MD 20705-2350, USA
| | - Xiao-Guang Chen
- Department of Pathogen Biology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515, China
| | - Zhijian Tu
- Department of Biochemistry and the Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA
| | - Igor V Sharakhov
- Department of Entomology and the Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA.,Laboratory of Ecology, Genetics and Environmental Protection, Tomsk State University, Tomsk, Russia
| | - Maria V Sharakhova
- Department of Entomology and the Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA.,Laboratory of Ecology, Genetics and Environmental Protection, Tomsk State University, Tomsk, Russia
| | - Robert Sebra
- Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | | | | | - Granger G Sutton
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850, USA
| | - Adam M Phillippy
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, Bethesda, MD 20892, USA
| | - Peter M Piermarini
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850, USA.,Department of Entomology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691, USA
| | - Reed S Shabman
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850, USA.,ATCC, 217 Perry Parkway, Gaithersburg, MD 20877, USA
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2
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Shrivastava S, Puri V, Dilley KA, Ngouajio E, Shifflett J, Oldfield LM, Fedorova NB, Hu L, Williams T, Durbin A, Amedeo P, Rashid S, Shabman RS, Pickett BE. Whole genome sequencing, variant analysis, phylogenetics, and deep sequencing of Zika virus strains. Sci Rep 2018; 8:15843. [PMID: 30367096 PMCID: PMC6203802 DOI: 10.1038/s41598-018-34147-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 10/08/2018] [Indexed: 12/25/2022] Open
Abstract
The recent emergence of Zika virus (ZIKV) has been concentrated in the Caribbean, Southeastern United States, and South- and Central America; resulting in travel-based cases being reported around the globe. As multi-disciplinary collaborations are combatting the ZIKV outbreak, the need to validate the sequence of existing strains has become apparent. Here, we report high-quality sequence data for multiple ZIKV strains made publicly available through the National Institutes of Health- (NIH) funded biorepository, BEI Resources (www.beiresources.org). Next-generation sequencing, 3' rapid amplification of cDNA ends (RACE), and viral genome annotation pipelines generated GenBank sequence records for 16 BEI Resources strains. Minor variants, consensus mutations, and consensus insertions/deletions were identified within the viral stocks using next-generation sequencing (NGS) and consensus changes were confirmed with Sanger sequencing. Bioinformatics analyses of the sequencing results confirm that the virus stocks available to the scientific research community through BEI Resources adequately represent the viral population diversity of ZIKV.
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Affiliation(s)
| | - Vinita Puri
- J. Craig Venter Institute, Rockville, MD, USA
| | - Kari A Dilley
- J. Craig Venter Institute, Rockville, MD, USA
- Sharp Edge Labs, Pittsburgh, PA, USA
| | - Erica Ngouajio
- J. Craig Venter Institute, Rockville, MD, USA
- University of Maryland, College Park, MD, USA
| | | | | | | | - Lihui Hu
- J. Craig Venter Institute, Rockville, MD, USA
| | | | - Alan Durbin
- J. Craig Venter Institute, La Jolla, CA, USA
| | | | | | - Reed S Shabman
- J. Craig Venter Institute, Rockville, MD, USA
- American Type Culture Collection, Manassas, VA, USA
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3
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Abstract
Background: The tick cell line ISE6, derived from
Ixodes scapularis, is commonly used for amplification and detection of arboviruses in environmental or clinical samples. Methods: To assist with sequence-based assays, we sequenced the ISE6 genome with single-molecule, long-read technology. Results: The draft assembly appears near complete based on gene content analysis, though it appears to lack some instances of repeats in this highly repetitive genome. The assembly appears to have separated the haplotypes at many loci. DNA short read pairs, used for validation only, mapped to the cell line assembly at a higher rate than they mapped to the
Ixodes scapularis reference genome sequence. Conclusions: The assembly could be useful for filtering host genome sequence from sequence data obtained from cells infected with pathogens.
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Affiliation(s)
- Jason R Miller
- J. Craig Venter Institute, Rockville, MD, 20850, USA.,Shepherd University, Shepherdstown, WV, 25443, USA
| | - Sergey Koren
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, Bethesda, MD, 20892, USA
| | - Kari A Dilley
- J. Craig Venter Institute, Rockville, MD, 20850, USA
| | | | - Timothy B Stockwell
- J. Craig Venter Institute, Rockville, MD, 20850, USA.,NBACC, Fort Detrick, MD, 21702, USA
| | - Reed S Shabman
- J. Craig Venter Institute, Rockville, MD, 20850, USA.,ATCC, Gaithersburg, MD, 20877, USA
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4
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Miller JR, Dilley KA, Harkins DM, Stockwell TB, Shabman RS, Sutton GG. A host subtraction database for virus discovery in human cell line sequencing data. F1000Res 2018; 7:98. [PMID: 31231504 PMCID: PMC6556987 DOI: 10.12688/f1000research.13580.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/17/2019] [Indexed: 11/28/2022] Open
Abstract
The human cell lines HepG2, HuH-7, and Jurkat are commonly used for amplification of the RNA viruses present in environmental samples. To assist with assays by RNAseq, we sequenced these cell lines and developed a subtraction database that contains sequences expected in sequence data from uninfected cells. RNAseq data from cell lines infected with Sendai virus were analyzed to test host subtraction. The process of mapping RNAseq reads to our subtraction database vastly reduced the number non-viral reads in the dataset to allow for efficient secondary analyses.
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Affiliation(s)
- Jason R Miller
- J. Craig Venter Institute, Rockville, MD, 20850, USA.,Shepherd University, Shepherdstown, WV, 25443, USA
| | - Kari A Dilley
- J. Craig Venter Institute, Rockville, MD, 20850, USA
| | | | - Timothy B Stockwell
- J. Craig Venter Institute, Rockville, MD, 20850, USA.,National Biodefense Analysis and Countermeasures Center (NBACC), Fort Detrick, MD, 21702, USA
| | - Reed S Shabman
- J. Craig Venter Institute, Rockville, MD, 20850, USA.,American Type Culture Collection, Gaithersburg, MD, 20877, USA
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5
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Obajemu AA, Rao N, Dilley KA, Vargas JM, Sheikh F, Donnelly RP, Shabman RS, Meissner EG, Prokunina-Olsson L, Onabajo OO. IFN-λ4 Attenuates Antiviral Responses by Enhancing Negative Regulation of IFN Signaling. J Immunol 2017; 199:3808-3820. [PMID: 29070670 DOI: 10.4049/jimmunol.1700807] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 09/27/2017] [Indexed: 12/20/2022]
Abstract
Type III IFNs are important mediators of antiviral immunity. IFN-λ4 is a unique type III IFN because it is produced only in individuals who carry a dG allele of a genetic variant rs368234815-dG/TT. Counterintuitively, those individuals who can produce IFN-λ4, an antiviral cytokine, are also less likely to clear hepatitis C virus infection. In this study, we searched for unique functional properties of IFN-λ4 that might explain its negative effect on hepatitis C virus clearance. We used fresh primary human hepatocytes (PHHs) treated with recombinant type III IFNs or infected with Sendai virus to model acute viral infection and subsequently validated our findings in HepG2 cell line models. Endogenous IFN-λ4 protein was detectable only in Sendai virus-infected PHHs from individuals with the dG allele, where it was poorly secreted but highly functional, even at concentrations < 50 pg/ml. IFN-λ4 acted faster than other type III IFNs in inducing antiviral genes, as well as negative regulators of the IFN response, such as USP18 and SOCS1 Transient treatment of PHHs with IFN-λ4, but not IFN-λ3, caused a strong and sustained induction of SOCS1 and refractoriness to further stimulation with IFN-λ3. Our results suggest unique functional properties of IFN-λ4 that can be important in viral clearance and other clinical conditions.
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Affiliation(s)
- Adeola A Obajemu
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Nina Rao
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Kari A Dilley
- Virology Group, J. Craig Venter Institute, Rockville, MD 20850
| | - Joselin M Vargas
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Faruk Sheikh
- Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993; and
| | - Raymond P Donnelly
- Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993; and
| | - Reed S Shabman
- Virology Group, J. Craig Venter Institute, Rockville, MD 20850
| | - Eric G Meissner
- Division of Infectious Diseases, Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC 29425
| | - Ludmila Prokunina-Olsson
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Olusegun O Onabajo
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892;
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6
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Dilley KA, Voorhies AA, Luthra P, Puri V, Stockwell TB, Lorenzi H, Basler CF, Shabman RS. The Ebola virus VP35 protein binds viral immunostimulatory and host RNAs identified through deep sequencing. PLoS One 2017. [PMID: 28636653 PMCID: PMC5479518 DOI: 10.1371/journal.pone.0178717] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Ebola virus and Marburg virus are members of the Filovirdae family and causative agents of hemorrhagic fever with high fatality rates in humans. Filovirus virulence is partially attributed to the VP35 protein, a well-characterized inhibitor of the RIG-I-like receptor pathway that triggers the antiviral interferon (IFN) response. Prior work demonstrates the ability of VP35 to block potent RIG-I activators, such as Sendai virus (SeV), and this IFN-antagonist activity is directly correlated with its ability to bind RNA. Several structural studies demonstrate that VP35 binds short synthetic dsRNAs; yet, there are no data that identify viral immunostimulatory RNAs (isRNA) or host RNAs bound to VP35 in cells. Utilizing a SeV infection model, we demonstrate that both viral isRNA and host RNAs are bound to Ebola and Marburg VP35s in cells. By deep sequencing the purified VP35-bound RNA, we identified the SeV copy-back defective interfering (DI) RNA, previously identified as a robust RIG-I activator, as the isRNA bound by multiple filovirus VP35 proteins, including the VP35 protein from the West African outbreak strain (Makona EBOV). Moreover, RNAs isolated from a VP35 RNA-binding mutant were not immunostimulatory and did not include the SeV DI RNA. Strikingly, an analysis of host RNAs bound by wild-type, but not mutant, VP35 revealed that select host RNAs are preferentially bound by VP35 in cell culture. Taken together, these data support a model in which VP35 sequesters isRNA in virus-infected cells to avert RIG-I like receptor (RLR) activation.
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Affiliation(s)
- Kari A. Dilley
- Virology Group, J. Craig Venter Institute, Rockville, Maryland, United States of America
- * E-mail: (RSS); (KAD)
| | - Alexander A. Voorhies
- Infectious Disease Group, J. Craig Venter Institute, Rockville, Maryland, United States of America
| | - Priya Luthra
- Center for Microbial Pathogenesis, Georgia State University, Atlanta, Georgia, United States of America
| | - Vinita Puri
- Virology Group, J. Craig Venter Institute, Rockville, Maryland, United States of America
| | - Timothy B. Stockwell
- Virology Group, J. Craig Venter Institute, Rockville, Maryland, United States of America
| | - Hernan Lorenzi
- Infectious Disease Group, J. Craig Venter Institute, Rockville, Maryland, United States of America
| | - Christopher F. Basler
- Center for Microbial Pathogenesis, Georgia State University, Atlanta, Georgia, United States of America
| | - Reed S. Shabman
- Virology Group, J. Craig Venter Institute, Rockville, Maryland, United States of America
- * E-mail: (RSS); (KAD)
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7
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Miller JR, Dilley KA, Harkins DM, Torralba MG, Moncera KJ, Beeri K, Goglin K, Stockwell TB, Sutton GG, Shabman RS. Initial genome sequencing of the sugarcane CP 96-1252 complex hybrid. F1000Res 2017; 6:688. [PMID: 28721204 PMCID: PMC5497815 DOI: 10.12688/f1000research.11629.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/17/2017] [Indexed: 11/20/2022] Open
Abstract
The CP 96-1252 cultivar of sugarcane is a complex hybrid of commercial importance. DNA was extracted from lab-grown leaf tissue and sequenced. The raw Illumina DNA sequencing results provide 101 Gbp of genome sequence reads. The dataset is available from https://www.ncbi.nlm.nih.gov/bioproject/PRJNA345486/.
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Affiliation(s)
| | - Kari A Dilley
- J. Craig Venter Institute, Rockville, MD, 20850, USA
| | | | | | | | - Karen Beeri
- J. Craig Venter Institute, La Jolla, CA, 92037, USA
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8
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Onabajo OO, Rao N, Obajemu AA, Dilley KA, Sheikh F, Donnelly R, Shabman RS, Prokunina-Olsson L. IFN-λ4 induces a faster but more transient antiviral response compared to other type III interferons. The Journal of Immunology 2017. [DOI: 10.4049/jimmunol.198.supp.158.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
IFN-λ4, a recently discovered type-III interferon (IFN), is genetically regulated, and has clinical significance because of its association with impaired clearance of hepatitis C virus (HCV) infection. Type-III IFNs play a critical role in the innate immune response to viral infections. Although IFN-λ4 induces a similar antiviral profile as other type-III IFNs, its specific contribution to the innate immune response is unclear. Delineating the functional properties of IFN-λ4 that distinguish it from other type-III IFNs may give insights into its unique role during HCV, and other infections. Here we compared antiviral responses induced by all four type-III IFNs in HepG2 cells. We show that IFN-λ4 attained 50% peak antiviral activity by 4 hours while other type-III IFNs were only at 20% of peak activity at this time. The rapid antiviral response induced by IFN-λ4 was followed by a sharp decline to less than 25% of peak activity within 24 hours, while activity of other type-III IFNs were still over 60% from peak.
By comparing antiviral activity of IFN-λ4 and IFN-λ3 against Sendai virus infection in primary human hepatocytes, we show that IFN-λ4 had stronger antiviral activity than IFN-λ3 early in the course of infection, but comparable activity at later time points. We also show that despite its poor secretion, IFN-λ4 was significantly more potent than IFN-λ3 in inducible cell lines engineered to express either protein. In summary, we show that IFN-λ4 is more active during the early stages of viral infection compared to other type-III IFNs, which maybe a clinically important window for restricting viral infection in the host, and affecting disease outcome.
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9
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Nikolaitchik OA, Dilley KA, Fu W, Gorelick RJ, Tai SHS, Soheilian F, Ptak RG, Nagashima K, Pathak VK, Hu WS. Dimeric RNA recognition regulates HIV-1 genome packaging. PLoS Pathog 2013; 9:e1003249. [PMID: 23555259 PMCID: PMC3605237 DOI: 10.1371/journal.ppat.1003249] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 01/30/2013] [Indexed: 11/18/2022] Open
Abstract
How retroviruses regulate the amount of RNA genome packaged into each virion has remained a long-standing question. Our previous study showed that most HIV-1 particles contain two copies of viral RNA, indicating that the number of genomes packaged is tightly regulated. In this report, we examine the mechanism that controls the number of RNA genomes encapsidated into HIV-1 particles. We hypothesize that HIV-1 regulates genome packaging by either the mass or copy number of the viral RNA. These two distinct mechanisms predict different outcomes when the genome size deviates significantly from that of wild type. Regulation by RNA mass would result in multiple copies of a small genome or one copy of a large genome being packaged, whereas regulation by copy number would result in two copies of a genome being packaged independent of size. To distinguish between these two hypotheses, we examined the packaging of viral RNA that was larger (≈17 kb) or smaller (≈3 kb) than that of wild-type HIV-1 (≈9 kb) and found that most particles packaged two copies of the viral genome regardless of whether they were 17 kb or 3 kb. Therefore, HIV-1 regulates RNA genome encapsidation not by the mass of RNA but by packaging two copies of RNA. To further explore the mechanism that governs this regulation, we examined the packaging of viral RNAs containing two packaging signals that can form intermolecular dimers or intramolecular dimers (self-dimers) and found that one self-dimer is packaged. Therefore, HIV-1 recognizes one dimeric RNA instead of two copies of RNA. Our findings reveal that dimeric RNA recognition is the key mechanism that regulates HIV-1 genome encapsidation and provide insights into a critical step in the generation of infectious viruses.
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Affiliation(s)
- Olga A. Nikolaitchik
- HIV Drug Resistance Program, National Cancer Institute, Frederick, Maryland, United States of America
| | - Kari A. Dilley
- HIV Drug Resistance Program, National Cancer Institute, Frederick, Maryland, United States of America
| | - William Fu
- Southern Research Institute, Frederick, Maryland, United States of America
| | - Robert J. Gorelick
- AIDS and Cancer Virology Program, SAIC-Frederick Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - S.-H. Sheldon Tai
- HIV Drug Resistance Program, National Cancer Institute, Frederick, Maryland, United States of America
| | - Ferri Soheilian
- Electron Microscopy Laboratory, SAIC-Frederick Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - Roger G. Ptak
- Southern Research Institute, Frederick, Maryland, United States of America
| | - Kunio Nagashima
- Electron Microscopy Laboratory, SAIC-Frederick Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - Vinay K. Pathak
- HIV Drug Resistance Program, National Cancer Institute, Frederick, Maryland, United States of America
| | - Wei-Shau Hu
- HIV Drug Resistance Program, National Cancer Institute, Frederick, Maryland, United States of America
- * E-mail:
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10
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Abstract
In sepsis, dysregulation of the inflammatory system is well known, as reflected in excessive inflammatory mediator production, complement activation, and appearance of defects in phagocytic cells. In the current study sepsis was induced in rats by cecal ligation/puncture. Early in sepsis the beta(1) and beta(2) integrin content on blood neutrophils increased in a nontranscriptional manner, and the increase in beta(2), but not beta(1), integrin content was C5a dependent. Similar changes could be induced in vitro on blood neutrophils following contact with phorbol ester or C5a. Direct injury of lungs of normal rats induced by deposition of IgG immune complexes (IgG-IC) caused 5-fold increases in the myeloperoxidase content that was beta(2), but not beta(1), dependent. In contrast, in cecal ligation/puncture lungs myeloperoxidase increased 10-fold after IgG immune complex deposition and was both beta(1) and beta(2) integrin dependent. These data suggest that sepsis causes enhanced neutrophil trafficking into the lung via mechanisms that are not engaged in the nonseptic state.
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Affiliation(s)
- Ren-Feng Guo
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109-0602, USA
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11
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Hlaing T, Guo RF, Dilley KA, Loussia JM, Morrish TA, Shi MM, Vincenz C, Ward PA. Molecular cloning and characterization of DEFCAP-L and -S, two isoforms of a novel member of the mammalian Ced-4 family of apoptosis proteins. J Biol Chem 2001; 276:9230-8. [PMID: 11076957 DOI: 10.1074/jbc.m009853200] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report the deduced amino acid sequences of two alternately spliced isoforms, designated DEFCAP-L and -S, that differ in 44 amino acids and encode a novel member of the mammalian Ced-4 family of apoptosis proteins. Similar to the other mammalian Ced-4 proteins (Apaf-1 and Nod1), DEFCAP contains a caspase recruitment domain (CARD) and a putative nucleotide binding domain, signified by a consensus Walker's A box (P-loop) and B box (Mg(2+)-binding site). Like Nod1, but different from Apaf-1, DEFCAP contains a putative regulatory domain containing multiple leucine-rich repeats (LRR). However, a distinguishing feature of the primary sequence of DEFCAP is that DEFCAP contains at its NH(2) terminus a pyrin-like motif and a proline-rich sequence, possibly involved in protein-protein interactions with Src homology domain 3-containing proteins. By using in vitro coimmunoprecipitation experiments, both long and short isoforms were capable of strongly interacting with caspase-2 and exhibited a weaker interaction with caspase-9. Transient overexpression of full-length DEFCAP-L, but not DEFCAP-S, in breast adenocarcinoma cells MCF7 resulted in significant levels of apoptosis. In vitro death assays with transient overexpression of deletion constructs of both isoforms using beta-galactosidase as a reporter gene in MCF7 cells suggest the following: 1) the nucleotide binding domain may act as a negative regulator of the killing activity of DEFCAP; 2) the LRR/CARD represents a putative constitutively active inducer of apoptosis; 3) the killing activity of LRR/CARD is inhibitable by benzyloxycarbonyl-Val-Ala-Asp (OMe)-fluoromethyl ketone and to a lesser extent by Asp-Glu-Val-Asp (OMe)-fluoromethyl ketone; and 4) the CARD is critical for killing activity of DEFCAP. These results suggest that DEFCAP is a novel member of the mammalian Ced-4 family of proteins capable of inducing apoptosis, and understanding its regulation may elucidate the complex nature of the mammalian apoptosis-promoting machinery.
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Affiliation(s)
- T Hlaing
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA
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