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Oh JN, Choi KH, Lee CK. Multi-resistance strategy for viral diseases and in vitro short hairpin RNA verification method in pigs. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2017; 31:489-498. [PMID: 29268580 PMCID: PMC5838320 DOI: 10.5713/ajas.17.0749] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/21/2017] [Accepted: 11/24/2017] [Indexed: 11/27/2022]
Abstract
Objective Foot and mouth disease (FMD) and porcine reproductive and respiratory syndrome (PRRS) are major diseases that interrupt porcine production. Because they are viral diseases, vaccinations are of only limited effectiveness in preventing outbreaks. To establish an alternative multi-resistant strategy against FMD virus (FMDV) and PRRS virus (PRRSV), the present study introduced two genetic modification techniques to porcine cells. Methods First, cluster of differentiation 163 (CD163), the PRRSV viral receptor, was edited with the clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 technique. The CD163 gene sequences of edited cells and control cells differed. Second, short hairpin RNA (shRNAs) were integrated into the cells. The shRNAs, targeting the 3D gene of FMDV and the open reading frame 7 (ORF7) gene of PRRSV, were transferred into fibroblasts. We also developed an in vitro shRNA verification method with a target gene expression vector. Results shRNA activity was confirmed in vitro with vectors that expressed the 3D and ORF7 genes in the cells. Cells containing shRNAs showed lower transcript levels than cells with only the expression vectors. The shRNAs were integrated into CD163-edited cells to combine the two techniques, and the viral genes were suppressed in these cells. Conclusion We established a multi-resistant strategy against viral diseases and an in vitro shRNA verification method.
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Affiliation(s)
- Jong-Nam Oh
- Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Kwang-Hwan Choi
- Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Chang-Kyu Lee
- Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea.,Designed Animal and Transplantation Research Institute (DATRI), Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea
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Yeo DSY, Lian JE, Fernandez CJ, Lin YN, Liaw JCW, Soh ML, Lim EAS, Chan KP, Ng ML, Tan HC, Oh S, Ooi EE, Tan BH. A highly divergent Encephalomyocarditis virus isolated from nonhuman primates in Singapore. Virol J 2013; 10:248. [PMID: 23914943 PMCID: PMC3750836 DOI: 10.1186/1743-422x-10-248] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 07/24/2013] [Indexed: 02/05/2023] Open
Abstract
Background In 2001 and 2002, fatal myocarditis resulted in the sudden deaths of four, two adult and two juvenile, orang utans out of a cohort of 26 in the Singapore Zoological Gardens. Methods Of the four orang utans that underwent post-mortem examination, virus isolation was performed from the tissue homogenates of the heart and lung obtained from the two juvenile orang utans in Vero cell cultures. The tissue culture fluid was examined using electron microscopy. Reverse transcription and polymerase chain reaction with Encephalomyocarditis virus (EMCV)-specific primers targeting the gene regions of VP3/VP1 and 3D polymerase (3Dpol) confirmed the virus genus and species. The two EMCV isolates were sequenced and phylogenetic analyses of the virus genes performed. Serological testing on other animal species in the Singapore Zoological Gardens was also conducted. Results Electron microscopy of the two EMCV isolates, designated Sing-M100-02 and Sing-M105-02, revealed spherical viral particles of about 20 to 30 nm, consistent with the size and morphology of members belonging to the family Picornaviridae. In addition, infected-Vero cells showed positive immunoflorescence staining with antiserum to EMCV. Sequencing of the viral genome showed that the two EMCV isolates were 99.9% identical at the nucleotide level, indicating a similar source of origin. When compared with existing EMCV sequences in the VP1 and 3Dpol gene regions, the nucleotide divergence were at a maximum of 38.8% and 23.6% respectively, while the amino acid divergence were at a maximum of 33.9% and 11.3% respectively. Phylogenetic analyses of VP1 and 3Dpol genes further grouped the Sing-M100-02 and Sing-M105-02 isolates to themselves, away from existing EMCV lineages. This strongly suggested that Sing-M100-02 and Sing-M105-02 isolates are highly divergent variants of EMCV. Apart from the two deceased orang utans, a serological survey conducted among other zoo animals showed that a number of other animal species had neutralizing antibodies to Sing-M105-02 isolate, indicating that the EMCV variant has a relatively wide host range. Conclusions The etiological agent responsible for the fatal myocarditis cases among two of the four orang utans in the Singapore Zoological Gardens was a highly divergent variant of EMCV. This is the first report of an EMCV infection in Singapore and South East Asia.
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Ma XX, Feng YP, Liu JL, Ma B, Chen L, Zhao YQ, Guo PH, Guo JZ, Ma ZR, Zhang J. The effects of the codon usage and translation speed on protein folding of 3Dpol of foot-and-mouth disease virus. Vet Res Commun 2013; 37:243-50. [DOI: 10.1007/s11259-013-9564-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2013] [Indexed: 10/26/2022]
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Abstract
Current understanding of the molecular basis of pathogenesis of foot-and-mouth disease (FMD) has been achieved through over 100 years of study into the biology of the etiologic agent, FMDV. Over the last 40 years, classical biochemical and physical analyses of FMDV grown in cell culture have helped to reveal the structure and function of the viral proteins, while knowledge gained by the study of the virus' genetic diversity has helped define structures that are essential for replication and production of disease. More recently, the availability of genetic engineering methodology has permitted the direct testing of hypotheses formulated concerning the role of individual RNA structures, coding regions and polypeptides in viral replication and disease. All of these approaches have been aided by the simultaneous study of other picornavirus pathogens of animals and man, most notably poliovirus. Although many questions of how FMDV causes its devastating disease remain, the following review provides a summary of the current state of knowledge into the molecular basis of the virus' interaction with its host that produces one of the most contagious and frightening diseases of animals or man.
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Affiliation(s)
- Peter W Mason
- USDA, ARS Plum Island Animal Disease Center, ARS. PO Box 848, Greenport, NY 11944, USA.
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5
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Domingo E, Escarmís C, Baranowski E, Ruiz-Jarabo CM, Carrillo E, Núñez JI, Sobrino F. Evolution of foot-and-mouth disease virus. Virus Res 2003; 91:47-63. [PMID: 12527437 DOI: 10.1016/s0168-1702(02)00259-9] [Citation(s) in RCA: 221] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Foot-and-mouth disease virus evolution is strongly influenced by high mutation rates and a quasispecies dynamics. Mutant swarms are subjected to positive selection, negative selection and random drift of genomes. Adaptation is the result of selective amplification of subpopulations of genomes. The extent of adaptation to a given environment is quantified by a relative fitness value. Fitness values depend on the virus and its physical and biological environment. Generally, infections involving large population passages result in fitness gain and population bottlenecks lead to fitness loss. Very different types of mutations tend to accumulate in the foot-and-mouth disease virus (FMDV) genome depending on the virus population size during replication. Quasispecies dynamics predict higher probability of success of antiviral strategies based on multivalent vaccines and combination therapy, and this has been supported by clinical and veterinary practice. Quasispecies suggest also new antiviral strategies based on virus entry into error catastrophe, and such procedures are under investigation. Studies with FMDV have contributed to the understanding of quasispecies dynamics and some of its biological implications.
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Affiliation(s)
- Esteban Domingo
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
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6
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Vanderhallen H, Koenen F. Identification of encephalomyocarditis virus in clinical samples by reverse transcription-PCR followed by genetic typing using sequence analysis. J Clin Microbiol 1998; 36:3463-7. [PMID: 9817855 PMCID: PMC105222 DOI: 10.1128/jcm.36.12.3463-3467.1998] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/1998] [Accepted: 09/01/1998] [Indexed: 11/20/2022] Open
Abstract
The objective of the present study was to gain a better understanding of the epidemiology of encephalomyocarditis virus (EMCV) infections in pigs by applying molecular techniques. The diagnostic potential of a reverse transcription-PCR (RT-PCR) targeting 286 nucleotides at the 3' end of the gene which encodes the viral polymerase was assessed with experimental and field samples. In addition, the use of the amplified sequences for an epidemiological study was evaluated. The heart was clearly shown to be the most suitable organ. The detection limit was determined to be 1 viral particle in 100 mg of heart tissue. The sensitivity and specificity of the assay on the basis of the results obtained in this study were 94 and 100%, respectively. Phylogenetic analysis of the amplified sequences classified EMCVs in two distinct lineages. Group A consists of the reference strain ATCC 129B, all isolates collected between 1991 and 1994 in Belgium in association with reproductive failure, and all Greek isolates. All Belgian isolates collected since the first isolation of EMCV in relation to myocardial failure in fatteners in Belgium group together with the isolates from Cyprus (1996 and 1997), Italy (1986 to 1996), and France (1995) in group B irrespective of their pathogenicity. The analyzed part of the 3D gene differed by 13.0% between Groups A and B. In contrast to the sequence homogeneity of the Belgian isolates collected between 1991 and 1994, molecular diversity, which ranged between 0 and 2%, was observed among the Belgian isolates collected in 1995 and 1996. Among all Greek isolates the diversity ranged between 1 and 8%. However, this diversity does not seem to reflect geographical links between the outbreaks. A RT-PCR for the rapid and specific diagnosis of EMCV in a variety of clinical samples followed by nucleotide sequence analysis proved to be valuable for molecular epidemiological studies.
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Affiliation(s)
- H Vanderhallen
- Veterinary and Agrochemic Research Center (CODA/CERVA), B-1180 Ukkel, Belgium
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7
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Quiñones-Mateu ME, Holguín A, Dopazo J, Nájera I, Domingo E. Point mutant frequencies in the pol gene of human immunodeficiency virus type 1 are two- to threefold lower than those of env. AIDS Res Hum Retroviruses 1996; 12:1117-28. [PMID: 8844016 DOI: 10.1089/aid.1996.12.1117] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Nucleotide sequences have been determined for the HIV-1 genomic regions encoding codons 41-108 and 181-219 of reverse transcriptase (RT) (pol gene), and codons 198-331 of gp120 (the C2V3 domains; env gene). Eighty-one HIV-1 samples from patients treated or untreated with RT inhibitors were used to sequence pol and 28 HIV-1 samples were used to sequence env. Several individual quasispecies have also been analyzed. All HIV-1 isolates belonged to subtype B. Point mutant frequencies and nucleotide diversities for pol were at most two- to threefold lower than env, with the proportion of nonsynonymous mutations ranging from 33 to 67%. A new variability index that takes into account the type of amino acid substitution as well as genetic distances between the compared sequences is introduced, and its main features for sequence comparisons emphasized. Extension of the calculations to gag, pol, and env sequences contained in the current HIV-1 database confirmed the high mutant frequencies for all HIV-1 genomic regions. The results indicate that although env is more tolerant to insertions and deletions than pol, point mutant frequencies for HIV-1 regions encoding nonstructural proteins are only two- to threefold lower than for regions encoding structural proteins. This implies the occurrence of frequent changes in HIV-1 phenotypes that are dependent on amino acid substitutions in viral enzymes.
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Affiliation(s)
- M E Quiñones-Mateu
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Spain
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8
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Escarmís C, Dopazo J, Dávila M, Palma EL, Domingo E. Large deletions in the 5'-untranslated region of foot-and-mouth disease virus of serotype C. Virus Res 1995; 35:155-67. [PMID: 7762289 DOI: 10.1016/0168-1702(94)00091-p] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Nucleotide sequences of the 5'-untranslated region (5'-UTR), at the 3'-side of the poly C tract, have been compared for 21 isolates of foot-and-mouth disease virus (FMDV) of serotype C from Europe, South America and The Philippines. A deletion of 43 nucleotides is present in the European isolates as compared with most American isolates. A larger deletion of 86 nucleotides is present in some viruses from South America and The Philippines. These deletions include the loss of one or two pseudoknot structures predicted in this region of the 5'-UTR. In addition, multiple point mutations have allowed the derivation of a phylogenetic tree which defines a grouping of isolates very similar to that derived from the capsid gene sequences of the same viruses. The study provides evidence that deletion (or addition) events must be very frequent during evolution of FMDV type C, since viruses which are phylogenetically very closely related (they belong to the same tree branch) may differ in the presence or absence of these deletions. Implications for FMDV evolution are discussed.
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Affiliation(s)
- C Escarmís
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Spain
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9
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Martínez MA, Dopazo J, Hernández J, Mateu MG, Sobrino F, Domingo E, Knowles NJ. Evolution of the capsid protein genes of foot-and-mouth disease virus: antigenic variation without accumulation of amino acid substitutions over six decades. J Virol 1992; 66:3557-65. [PMID: 1316467 PMCID: PMC241137 DOI: 10.1128/jvi.66.6.3557-3565.1992] [Citation(s) in RCA: 111] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The genetic diversification of foot-and-mouth disease virus (FMDV) of serotype C over a 6-decade period was studied by comparing nucleotide sequences of the capsid protein-coding regions of viruses isolated in Europe, South America, and The Philippines. Phylogenetic trees were derived for VP1 and P1 (VP1, VP2, VP3, and VP4) RNAs by using the least-squares method. Confidence intervals of the derived phylogeny (significance levels of nodes and standard deviations of branch lengths) were placed by application of the bootstrap resampling method. These procedures defined six highly significant major evolutionary lineages and a complex network of sublines for the isolates from South America. In contrast, European isolates are considerably more homogeneous, probably because of the vaccine origin of several of them. The phylogenetic analysis suggests that FMDV CGC Ger/26 (one of the earliest FMDV isolates available) belonged to an evolutionary line which is now apparently extinct. Attempts to date the origin (ancestor) of the FMDVs analyzed met with considerable uncertainty, mainly owing to the stasis noted in European viruses. Remarkably, the evolution of the capsid genes of FMDV was essentially associated with linear accumulation of silent mutations but continuous accumulation of amino acid substitutions was not observed. Thus, the antigenic variation attained by FMDV type C over 6 decades was due to fluctuations among limited combinations of amino acid residues without net accumulation of amino acid replacements over time.
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Affiliation(s)
- M A Martínez
- Centro de Biología Molecular, Universidad Autónoma de Madrid, Spain
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10
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Domingo E, Holland JJ. Complications of RNA Heterogeneity for the Engineering of Virus Vaccines and Antiviral Agents. GENETIC ENGINEERING 1992; 14:13-31. [PMID: 1368276 DOI: 10.1007/978-1-4615-3424-2_2] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Affiliation(s)
- E Domingo
- Centro de Biología Molecular (CSIC-UAM), Universidad Autónoma de Madrid, Spain
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11
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Domingo E, Escarmis C, Martinez MA, Martinez-Salas E, Mateu MG. Foot-and-mouth disease virus populations are quasispecies. Curr Top Microbiol Immunol 1992; 176:33-47. [PMID: 1318185 DOI: 10.1007/978-3-642-77011-1_3] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- E Domingo
- Centro de Biologia Molecular, Universidad Autónoma de Madrid, Spain
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12
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Vidal M, Cairó J, Mateu MG, Villaverde A. Molecular cloning and expression of the VP1 gene of foot-and-mouth disease virus C1 in E. coli: effect on bacterial cell viability. Appl Microbiol Biotechnol 1991; 35:788-92. [PMID: 1369359 DOI: 10.1007/bf00169896] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The VP1 gene of foot-and-mouth disease virus (serotype C1) has been cloned in Escherichia coli Clts cells, under the control of the bacteriophage lambda pL promoter. The expressed VP1 protein was complete and non-fused, and its molecular weight was indistinguishable from that of the VP1 obtained from virions. Cells harbouring the recombinant vectors exhibited symptoms of plasmid instability and toxicity and died in a few weeks even when never exposed to inducing conditions. A new plasmid clone in which a segment of the VP1 gene was fused with contiguous genes of the viral genome was very stable. The expressed partial VP1 protein contains the two major immunogenic domains of the virion. This system can be used as a tool to design an immunogenic VP1, and to explore possible synthetic vaccines against foot-and-mouth disease.
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Affiliation(s)
- M Vidal
- Institut de Biologia Fonamental, Universitat Autònoma de Barcelona, Bellaterra, Spain
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Villaverde A, Martínez MA, Sobrino F, Dopazo J, Moya A, Domingo E. Fixation of mutations at the VP1 gene of foot-and-mouth disease virus. Can quasispecies define a transient molecular clock? Gene 1991; 103:147-53. [PMID: 1653754 DOI: 10.1016/0378-1119(91)90267-f] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The number of nucleotide (nt) substitutions found in the VP1 gene (encoding viral capsid protein) between any two of 16 closely related isolates of foot-and-mouth disease virus (FMDV) has been quantified as a function of the time interval between isolations [Villaverde et al., J. Mol. Biol. 204 (1988) 771-776]. One of them (isolate C-S12) includes some replacements found in isolates that preceded it and other replacements found in later isolates. The study has revealed alternating periods of rapid evolution and of relative genetic stability of VP1. During a defined period of acute disease, the rate of fixation of replacements at the VP1 coding segment was 6 x 10(-3) substitutions per nt per year. Only small differences in the rate of evolution were observed between subsegments within the VP1 gene. The observation of a relatively constant rate of evolution during a disease episode was unexpected. We propose that such constancy may be a consequence of random sampling of mutants from the FMDV quasispecies, followed by their amplification in susceptible hosts (to generate a new quasispecies). Successive sampling and amplification events may result in a steady accumulation of mutations.
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Affiliation(s)
- A Villaverde
- Instituto de Biología Fundamental y Universidad Autónoma de Barcelona, Spain
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Díez J, Dávila M, Escarmís C, Mateu MG, Dominguez J, Pérez JJ, Giralt E, Melero JA, Domingo E. Unique amino acid substitutions in the capsid proteins of foot-and-mouth disease virus from a persistent infection in cell culture. J Virol 1990; 64:5519-28. [PMID: 2170684 PMCID: PMC248604 DOI: 10.1128/jvi.64.11.5519-5528.1990] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Maintenance of a persistent foot-and-mouth disease virus (FMDV) infection in BHK-21 cells involves a coevolution of cells and virus (J. C. de la Torre, E. Martínez-Salas, J. Díez, A. Villaverde, F. Gebauer, E. Rocha, M. Dávila, and E. Domingo, J. Virol. 62:2050-2058, 1988). The resident FMDV undergoes a number of phenotypic changes, including a gradual decrease in virion stability. Here we report the nucleotide sequence of the P1 genomic segment of the virus rescued after 100 passages of the carrier cells (R100). Only 5 of 15 mutations in P1 of R100 were silent. Nine amino acid substitutions were fixed on the viral capsid during persistence, and three of the variant amino acids are not represented in the corresponding position of any picornavirus sequenced to date. Cysteine at position 7 of VP3, that provides disulfide bridges at the FMDV fivefold axis, was substituted by valine, as determined by RNA, cDNA, and protein sequencing. The modified virus shows high buoyant density in cesium chloride and depicts the same sensitivity to photoinactivation by intercalating dyes as the parental FMDV C-S8c1. Amino acid substitutions fixed in VP1 resulted in altered antigenicity, as revealed by reactivity with monoclonal antibodies. In addition to defining at the molecular level the alterations the FMDV capsid underwent during persistence, the results show that positions which are highly invariant in an RNA genome may change when viral replication occurs in a modified environment.
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Affiliation(s)
- J Díez
- Centro de Biología Molecular, Universidad Autónoma de Madrid, Spain
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Pietrokovski S, Hirshon J, Trifonov EN. Linguistic measure of taxonomic and functional relatedness of nucleotide sequences. J Biomol Struct Dyn 1990; 7:1251-68. [PMID: 2363847 DOI: 10.1080/07391102.1990.10508563] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The frequencies of "words", oligonucleotides within nucleotide sequences, reflect the genetic information contained in the sequence "texts". Nucleotide sequences are characteristically represented by their contrast word vocabularies. Comparison of the sequences by correlating their contrast vocabularies is shown to reflect well the relatedness (unrelatedness) between the sequences. A single value, the linguistic similarity between the sequences, is suggested as a measure of sequence relatedness. Sequences as short as 1000 bases can be characterized and quantitatively related to other sequences by this technique. The linguistic sequence similarity value is used for analysis of taxonomically and functionally diverse nucleotide sequences. The similarity value is shown to be very sensitive to the relatedness of the source species, thus providing a convenient tool for taxonomic classification of species by their sequence vocabularies. Functionally diverse sequences appear distinct by their linguistic similarity values. This can be a basis for a quick screening technique for functional characterization of the sequences and for mapping functionally distinct regions in long sequences.
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Affiliation(s)
- S Pietrokovski
- Department of Polymer Research, Weizmann Institute of Science, Rehovot, Israel
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Domingo E. RNA virus evolution and the control of viral disease. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 1989; 33:93-133. [PMID: 2687948 DOI: 10.1007/978-3-0348-9146-2_5] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
RNA viruses and other RNA genetic elements must be viewed as organized distributions of sequences termed quasi-species. This means that the viral genome is statistically defined but individually indeterminate. Stable distributions may be maintained for extremely long time periods under conditions of population equilibrium. Perturbation of equilibrium results in rapid distribution shifts. This genomic organization has many implications for viral pathogenesis and disease control. This review has emphasized the problem of selection of viral mutants resistant to antiviral drugs and the current difficulties encountered in the design of novel synthetic vaccines. Possible strategies for antiviral therapy and vaccine development have been discussed.
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