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1.
J Gen Virol ; 102(3)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-31922947

RESUMEN

Cases of pox-like lesions in horses and donkeys have been associated with poxviruses belonging to different genera of the family Poxviridae. These include the orthopoxviruses vaccinia virus (VACV), horsepoxvirus (HPXV) and cowpoxvirus (CPXV), as well as a potentially novel parapoxvirus and molluscum contagiosum virus (MOCV). However, with the exception of VACV, HPXV and CPXV, the genomic characterization of the causative agents remains largely elusive with only single short genome fragments available. Here we present the first full-length genome sequence of an equine molluscum contagiosum-like virus (EMCLV) directly determined from skin biopsies of a horse with generalized papular dermatitis. Histopathological analysis of the lesions revealed severe epidermal hyperplasia with numerous eosinophilic inclusion bodies within keratinocytes. Virions were detected in the lesions in embedded tissue by transmission electron microscopy. The genome sequence determined by next- and third-generation sequencing comprises 166 843 nt with inverted terminal repeats (ITRs) of 3473 nt. Overall, 20 of the predicted 159 ORFs have no equivalents in other poxviruses. Intriguingly, two of these ORFs were identified to encode homologues of mammalian proteins involved in immune signalling pathways, namely secreted and transmembrane protein 1 (SECTM1) and insulin growth factor-like family receptor 1 (IGFLR1), that were not described in any virus family so far. Phylogenetic analysis with all relevant representatives of the Poxviridae suggests that EMCLV should be nominated as a new species within the genus Molluscipoxvirus.


Asunto(s)
Genoma Viral , Enfermedades de los Caballos/virología , Molluscipoxvirus/genética , Molluscipoxvirus/fisiología , Infecciones por Poxviridae/veterinaria , Enfermedades Cutáneas Virales/veterinaria , Proteínas Virales/genética , Animales , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Caballos , Péptidos y Proteínas de Señalización Intercelular/química , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Molluscipoxvirus/aislamiento & purificación , Virus del Molusco Contagioso/genética , Sistemas de Lectura Abierta , Filogenia , Infecciones por Poxviridae/patología , Infecciones por Poxviridae/virología , Piel/patología , Piel/virología , Enfermedades Cutáneas Virales/patología , Enfermedades Cutáneas Virales/virología , Transcripción Genética , Proteínas Virales/química , Proteínas Virales/metabolismo , Replicación Viral/genética , Secuenciación Completa del Genoma
2.
Virus Genes ; 56(2): 150-167, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32076918

RESUMEN

The viruses historically implicated or currently considered as candidates for misuse in bioterrorist events are poxviruses, filoviruses, bunyaviruses, orthomyxoviruses, paramyxoviruses and a number of arboviruses causing encephalitis, including alpha- and flaviviruses. All these viruses are of concern for public health services when they occur in natural outbreaks or emerge in unvaccinated populations. Recent events and intelligence reports point to a growing risk of dangerous biological agents being used for nefarious purposes. Public health responses effective in natural outbreaks of infectious disease may not be sufficient to deal with the severe consequences of a deliberate release of such agents. One important aspect of countermeasures against viral biothreat agents are the antiviral treatment options available for use in post-exposure prophylaxis. These issues were adressed by the organizers of the 16th Medical Biodefense Conference, held in Munich in 2018, in a special session on the development of drugs to treat infections with viruses currently perceived as a threat to societies or associated with a potential for misuse as biothreat agents. This review will outline the state-of-the-art methods in antivirals research discussed and provide an overview of antiviral compounds in the pipeline that are already approved for use or still under development.


Asunto(s)
Antivirales/uso terapéutico , Arbovirus/efectos de los fármacos , Bioterrorismo/prevención & control , Virosis/tratamiento farmacológico , Arbovirus/patogenicidad , Filoviridae/efectos de los fármacos , Filoviridae/patogenicidad , Humanos , Orthobunyavirus/efectos de los fármacos , Orthobunyavirus/patogenicidad , Orthomyxoviridae/efectos de los fármacos , Orthomyxoviridae/patogenicidad , Paramyxovirinae/efectos de los fármacos , Paramyxovirinae/patogenicidad , Poxviridae/efectos de los fármacos , Poxviridae/patogenicidad , Virosis/virología
3.
Eur J Neurol ; 17(11): 1386-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20482607

RESUMEN

BACKGROUND: Sero-epidemiological studies have demonstrated the association between multiple sclerosis (MS) and prior Epstein-Barr virus (EBV) infection. It has been hypothesized that intermittent peripheral EBV reactivation may drive continuing central inflammation. Recent investigation has shown significant differences in median serum levels of anti-EBV nuclear antigen-1 (EBNA-1) IgG between disease subgroups and positive correlation with disease activity reflected by number of Gd-enhancing lesions and T2 lesion volume. These important data have led to hopes that anti-EBNA-1 IgG may be useful as an easily accessible and effective biomarker of disease activity. METHODS: We examined the applicability of these findings in routine clinical practice, assessing a well-characterized cohort of 100 subjects (25 primary progressive, 25 stable relapsing remitting, 25 active relapsing remitting seen in acute relapse and 25 controls) for serum anti-EBNA-1 IgG using both the Liaison quantitative chemiluminescent assay and Biotest ELISA. RESULTS: We were unable to show a difference in quantitative analysis of serum anti-EBNA-1 IgG levels between disease subgroups and no correlation with phenotypic characteristics including age at onset (r = -0.17, P = 0.16), disease duration (r = 0.03, P = 0.78), EDSS (r = 0.03, P = 0.78) or MSSS (r = 0.02, P = 0.9). In addition, there was only moderate correlation between the two test methods used (intraclass correlation coefficient 0.67; 0.56-0.78) suggesting potential problems with test interpretation. CONCLUSIONS: We have been unable to determine a clinical value for serum anti-EBNA-1 IgG levels in MS or to confirm reported association with disease course and clinical disease activity.


Asunto(s)
Antígenos Nucleares del Virus de Epstein-Barr/inmunología , Inmunoglobulina G/sangre , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/inmunología , Adulto , Anciano , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Biomarcadores/metabolismo , Evaluación de la Discapacidad , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/sangre , Esclerosis Múltiple/clasificación
4.
Science ; 273(5276): 813-6, 1996 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-8670425

RESUMEN

Molluscum contagiosum virus (MCV) commonly causes asymptomatic cutaneous neoplasms in children and sexually active adults as well as persistent opportunistic acquired immunodeficiency syndrome (AIDS)-associated disease. Sequencing the 190-kilobase pair genome of MCV has now revealed that the virus potentially encodes 163 proteins, of which 103 have homologs in the smallpox virus. MCV lacks counterparts to 83 genes of the smallpox virus, including those important in suppression of host responses to infection, nucleotide biosynthesis, and cell proliferation. MCV possesses 59 genes that are predicted to encode previously uncharacterized proteins, including major histocompatibility complex class I, chemokine, and glutathione peroxidase homologs, which suggests that there are MCV-specific strategies for coexistence with the human host.


Asunto(s)
Genoma Viral , Virus del Molusco Contagioso/genética , Proteínas Virales/química , Secuencia de Aminoácidos , Composición de Base , Quimiocinas/química , Quimiocinas/genética , ADN Viral/genética , Glutatión Peroxidasa/química , Glutatión Peroxidasa/genética , Antígenos de Histocompatibilidad Clase I/química , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Datos de Secuencia Molecular , Virus del Molusco Contagioso/química , Virus del Molusco Contagioso/patogenicidad , Sistemas de Lectura Abierta , Orthopoxvirus/química , Orthopoxvirus/genética , Alineación de Secuencia , Virus de la Viruela/química , Virus de la Viruela/genética , Proteínas Virales/genética
5.
Arch Virol Suppl ; 13: 35-47, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9413524

RESUMEN

Molluscum contagiosum virus (MCV) and variola virus (VAR) are the only two poxviruses that are specific for man. MCV causes skin tumors in humans and primarily in children and immunocompromised individuals. MCV is unable to replicate in tissue culture cells or animals. Recently, the DNA sequence of the 190 kbp MCV genome was reported by Senkevich et al. MCV was predicted to encode 163 proteins of which 103 were clearly related to those of smallpox virus. In contrast, it was found that MCV lacks 83 genes of VAR, including those involved in the suppression of the host response to infection, nucleotide biosynthesis, and cell proliferation. However, MCV possesses 59 genes predicted to code for novel proteins including MHC-class I, chemokine and glutathione peroxidase homologs not found in other poxviruses. The MCV genomic data allow the investigation of novel host defense mechanisms and provide new possibilities for the development of therapeutics for treatment and prevention of the MCV infection.


Asunto(s)
Molusco Contagioso/virología , Virus del Molusco Contagioso , Animales , Genoma Viral , Humanos , Molusco Contagioso/diagnóstico , Molusco Contagioso/epidemiología , Molusco Contagioso/terapia , Virus del Molusco Contagioso/efectos de los fármacos , Virus del Molusco Contagioso/genética , Virus del Molusco Contagioso/crecimiento & desarrollo , Virus del Molusco Contagioso/aislamiento & purificación , Investigación
6.
J Med Virol ; 33(3): 211-7, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1880497

RESUMEN

The stability of the Molluscum contagiosum virus Type 1 genome (188 kbp) was studied in 184 DNA isolates from 131 patients. Variability of up to 1.5 kbp at both ends of the genome symmetrically was observed using restriction analysis of the DNA isolates and by Southern Blot experiments using cloned and labeled HindIII terminal DNA fragments of MCV-1 prototype DNA. The variable sequences were mainly confined to the terminal fragments and parts of the MCV-1 terminal repeats. Labeled probes did not detect terminal sequences of MCV Type 2 under the applied stringency. A less marked instability of the central MCV-1 BamHI DNA fragment F was observed within the genome coordinates 0.431 to 0.454 mu. Reiteration of tandem repeats similar to those described for vaccinia virus might explain the variability of the terminal sequences and might be involved in viral replication.


Asunto(s)
ADN Viral/química , Virus del Molusco Contagioso/genética , Secuencias Repetitivas de Ácidos Nucleicos , Southern Blotting , Reordenamiento Génico , Variación Genética , Humanos , Virus del Molusco Contagioso/análisis , Virus del Molusco Contagioso/clasificación , Hibridación de Ácido Nucleico , Mapeo Restrictivo
7.
Virus Genes ; 21(1-2): 111-33, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11022794

RESUMEN

Over the course of time poxviruses have acquired or "captured" numerous homologues of cellular genes and incorporated them into their large DNA genomes. With more poxvirus genome sequencing data becoming available, the number of newly discovered poxviral cellular homologues is constantly increasing. A common feature of these genes is that they are nonessential for virus replication in vitro and they confer selective advantages in dealing with host cell differentiation and immune defense mechanisms in vivo. Poxviral cellular homologues are reviewed in this synopsis considering the specific viral habitats of different poxviruses and the immune defence capabilities of their respective hosts. Possible mechanisms of cellular gene acquisition by poxviruses as suggested by the analysis of mobile genetic elements in large DNA viruses are discussed. The investigation of poxvirus homologues of cellular genes is essential for our understanding of the mechanisms that regulate virus/host interactions on the cellular level and the host response against infection.


Asunto(s)
Imitación Molecular , Infecciones por Poxviridae/inmunología , Poxviridae/genética , Poxviridae/patogenicidad , Proteínas Virales/genética , Proteínas Virales/fisiología , Animales , Humanos , Infecciones por Poxviridae/virología , Proteínas Virales/química
8.
Virus Genes ; 21(3): 189-92, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11129634

RESUMEN

Molluscum contagiosum virus (MCV) is a member of the poxvirus family and causes benign skin tumors in children and immunocompromised individuals. The primary structure and coding capacity of MCV was previously determined by DNA nucleotide sequencing (Senkevich et al., Science 273, 813-816, 1996). Hypothetical genes were predicted based on (i) amino acid homologies with known genes, (ii) presence or absence of conserved transcription regulation signals, and (iii) algorithms based on learning sets of coding sequences. These methods provide a rational basis for the prediction of MCV coding sequences. However, the existence and exact size of MCV open reading frames and the precise position of transcription regulation signals can only be determined by MCV mRNA transcript mapping experiments. We developed methods for the characterization of the mRNA transcripts of MCV genes in infected skin tissue and abortively infected human fibroblast cell cultures. Using these methods the properties of the mRNA transcripts of the MCV SLAM (signaling lymphocytic activating molecule) gene family (mc002L, mc161R, and mc162R) were analyzed. The mRNA start site found for the mc161R transcript suggests that a second start codon is used leading to a mc161R open reading frame that is nine amino acid residues shorter than predicted.


Asunto(s)
Virus del Molusco Contagioso/genética , ARN Mensajero , ARN Viral , Transcripción Genética , Antígenos CD , Secuencia de Bases , Mapeo Cromosómico , ADN Viral , Genoma Viral , Glicoproteínas , Humanos , Inmunoglobulinas , Datos de Secuencia Molecular , Molusco Contagioso/patología , Molusco Contagioso/virología , Receptores de Superficie Celular , Miembro 1 de la Familia de Moléculas Señalizadoras de la Activación Linfocitaria
9.
Virology ; 257(1): 119-29, 1999 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-10208926

RESUMEN

Molluscum contagiosum virus (MCV), a member of the family Poxviridae, replicates well in vivo but cannot be propagated in cell culture. The coding capacity of the MCV genome was previously determined by DNA nucleotide sequence analysis. The objective of the present study was to establish experimental systems for the identification and characterization of early MCV gene transcripts. MCV mRNA was obtained in three ways: (1) MCV early mRNA was synthesized in vitro using permeabilized virions, (2) MCV mRNA was extracted from MCV-infected skin tissue, and (3) MCV mRNA was extracted from MCV-infected human embryonic fibroblasts. RNA/DNA hybridization experiments showed significant early transcriptional activity in two parts of the MCV genome. Transcripts of 11 early MCV genes located in these parts of the genome, including two subunits of the MCV DNA-dependent RNA polymerase (mc077R and mc079R), the MCV poly(A)+ polymerase gene (mc076R), and the MCV MHC class I homolog (mc080R), were detected in reverse transcription-polymerase chain reaction experiments. Total RNA obtained from MCV-infected skin tissue was used to confirm these results. Three MCV early transcripts, mc002L, mc004.1L, and mc005L, produced distinct bands on rapid amplification of their 3' ends (3' RACE). The 5' mapping of transcription start sites of MCV open reading frames (ORFs) mc002L, mc004.1L, mc005L, and mc148R revealed that the MCV RNA polymerase transcription start sites are consistently located between 11 and 13 nucleotides downstream of the early MCV consensus promoter signal. When cDNA from both 5' and 3' mapping experiments was analyzed, MCV ORFs mc004. 1L and mc005L were found to be transcribed as a single bicistronic mRNA. The transcript from MCV ORF mc066L, encoding a glutathione peroxidase, was detected in in vitro synthesized MCV mRNA as well as in total RNA from MCV-infected human embryonic fibroblasts and MCV-infected skin. This indicates that despite the lack of an early MCV consensus promoter signal immediately proximal to the start codon, this particular gene is transcribed early during MCV infection.


Asunto(s)
ADN Viral/química , Virus del Molusco Contagioso/genética , Transcripción Genética , Secuencia de Bases , Humanos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , ARN Mensajero/química , ARN Mensajero/metabolismo , ARN Viral/química , ARN Viral/metabolismo , Técnica del ADN Polimorfo Amplificado Aleatorio , Alineación de Secuencia
10.
Virus Genes ; 22(1): 27-33, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11210936

RESUMEN

Molluscum contagiosum virus (MCV), a member of the family Poxviridae, can be isolated from skin-lesion material of patients with molluscum contagiosum infection. MCV replicates efficiently in human keratinocytes in vivo but viral replication has not been observed in vitro in cell or tissue culture systems. We investigated a variety of established cell lines for productive MCV infection and found that: (i) MCV induces a typical cytopathogenic effect (CPE) only in human primary fibroblast cells (MRC5 ATCC-CCL 171 and HEPM ATCC-CRL 1486) but not in permanent eucaryotic cell lines of human or simian origin; (ii) UV irradiated MCV virions and heat inactivated virions do not induce a CPE; (iii) decreasing amounts of MCV viral DNA are detectable in infected human embryonic fibroblasts for at least 14 days post infection (p.i.); (iv) MCV early mRNAs are detectable by RT-PCR between one and two hours p.i. and remain detectable upon passaging of the infected cells; (iv) transcripts of viral late genes (mc095L and mc106L) are detectable by RT-PCR from day 5 p.i.; (v) MCV viral antigens can be detected on the surface of infected cells using human and rabbit polyclonal antisera against MCV from 24 h p.i.; (vi) a CPE can not be observed if cell free supernatants or homogenizates of MCV infected cells are used to try passage of the virus onto uninfected human embryonic fibroblasts, indicating that infectious viral progeny is not produced. This is the first report demonstrating long time persistence of MCV viral DNA and expression of late proteins in an in vitro cell culture system.


Asunto(s)
Fibroblastos/virología , Expresión Génica , Virus del Molusco Contagioso/fisiología , Transcripción Genética , Proteínas Virales/biosíntesis , Animales , Línea Celular , Células Cultivadas , Efecto Citopatogénico Viral , Humanos , Molusco Contagioso/virología , Virus del Molusco Contagioso/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Virales/genética , Replicación Viral
11.
Virus Genes ; 3(2): 159-73, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2617850

RESUMEN

The genomes (188 kbp) of the prototype Molluscum contagiosum virus type 1 (MCV-1) and a variant strain (MCV-1v) were characterized by construction of the physical maps of the viral DNA for the restriction enzymes BamHI, ClaI, EcoRI, and HindIII using a defined gene library harboring the DNA sequences of the MCV-1 genome and by DNA-DNA hybridizations. It was found that the genomes of both MCV strains are identical, with the exception of very few changes in the DNA fragmentation patterns of restriction endonuclease BamHI as a consequence of naturally occurring nucleotide exchanges in the genome of the variant strain. Detailed hybridization experiments revealed the existence of repetitive DNA sequences, which are located within the terminal regions of the viral genome at the map coordinates 0 to 0.027 and 0.973 to 1.


Asunto(s)
ADN Viral/análisis , Molusco Contagioso/genética , Secuencias Repetitivas de Ácidos Nucleicos , Clonación Molecular , Mapeo Restrictivo
12.
Virology ; 192(1): 391-6, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8517030

RESUMEN

The repetitive DNA sequences of the genome of Molluscum contagiosum virus type 1 (MCV-1) have been localized within the terminal regions of the viral genome corresponding to the BamHI MCV-1 DNA fragments B (18 kbp; 0 to 0.095 map units (m.u.)) and E (10.5 kbp; 0.944 to 1 m.u.). The fine mapping of these particular regions of the genome of MCV-1 revealed that the boundaries of the terminal repetitive DNA sequences of the viral genome are located within the DNA sequences of the HindIII MCV-1 DNA fragments K (3.8 kbp; 0.014 to 0.036 m.u.) and J1 (4.1 kbp; 0.962 to 0.985 m.u.). The exact position of the boundary of the repetitive DNA sequences was determined by DNA nucleotide sequencing. The HindIII DNA fragments K and J1 compose 3859 and 4107 bp, respectively. The DNA sequences of HindIII MCV-1 DNA fragment K possess repetitive DNA sequences between the nucleotide positions 1 and 1675 which are homologous to the inverted and complementary DNA sequences of the HindIII MCV-1 DNA fragment J1 between the nucleotide positions 2437 and 4107 (1670 bp). The degree of DNA sequence homology detected between the repetitive DNA sequences in the HindIII DNA fragments K and J1 of the viral genome was found to be 98%. The number of open reading frames (ORFs) detected by the analysis of the DNA sequences of the HindIII MCV-1 DNA fragments K and J1 was found to be 14 (70 to 219 amino acid residues) and 11 (70 to 365 amino acid residues), respectively.


Asunto(s)
Poxviridae/genética , Secuencia de Bases , ADN Viral/genética , Genes Virales , Enlace de Hidrógeno , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Sistemas de Lectura Abierta , Secuencias Repetitivas de Ácidos Nucleicos , Mapeo Restrictivo , Alineación de Secuencia , Timidina Quinasa/genética , Proteínas Estructurales Virales/genética
13.
Intervirology ; 36(1): 32-43, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8225909

RESUMEN

The complete DNA nucleotide sequence of a HindIII/MluI genomic DNA fragment (0.045-0.075 viral map units) from molluscum contagiosum virus type 1 (MCV-1) was determined. The HindIII/MluI DNA fragment comprises 5,646 bp with a base composition of 64.4% G + C and 35.6% A + T. The DNA sequence contains many perfect direct repeats. A cluster of three repetitive DNA elements R1, R2 and R3, with a complex structural arrangement was detected between nucleotide positions 1802 and 2107. The unit length (box) of the repetitive DNA sequences was found to be 6 bp (15 boxes) and 9 bp (24 boxes) for R1 and R2, respectively. The repetitive DNA element R3 is organized in fifteen boxes (15 bp) in which a unit length of R1 is combined with a unit length of R2. The arrangement of the repetition R3 within the DNA sequences of this particular region of the MCV-1 genome was found to be (5 x R3) + (2 x R2) + (1 x R3) + (6 x R2) + (1 x R3) + (1 x R2) + (8 x R3). Twenty-three open reading frames (ORFs) of 60-1,175 amino acid (AA) residues were detected. The largest ORF (number 17) comprises 1,175 AA with a predicted molecular weight of 126 kD. This ORF harbors a promoter signal which is located 21 nucleotides upstream from the start codon and is very similar to the early promoter signals known for vaccinia virus. This putative protein contains glutamine-enriched regions between AA residues 427 and 682 which show homologies to the corresponding glutamine-enriched regions of a variety of cellular genes like human transcriptional initiation factor (TFIID: TATA box factor).


Asunto(s)
Proteínas Bacterianas , ADN Viral/genética , Genoma Viral , Virus del Molusco Contagioso/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Viral/metabolismo , Desoxirribonucleasa HindIII/metabolismo , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Biblioteca Genómica , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Secuencias Repetitivas de Ácidos Nucleicos , Análisis de Secuencia , Homología de Secuencia de Aminoácido , Factor de Transcripción TFIID , Factores de Transcripción/genética
14.
Virology ; 210(2): 471-8, 1995 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-7618282

RESUMEN

The DNA-dependent RNA polymerase (DdRP) is an essential enzyme for transcription of molluscum contagiosum virus (MCV), a member of the family Poxviridae which replicates in the cytoplasm of the infected cell. Using PCR technology and oligonucleotide primers, corresponding to two conserved domains (RQP[T/S]LH and NADFDGDE) of known largest subunits of eucaryotic and procaryotic DNA-dependent RNA polymerases, the DdRP gene of the genome of molluscum contagiosum virus type 1 (MCV-1) was identified and characterized. The oligonucleotide primers were designed according to the coding usage statistics of known open reading frames of the viral genome. The gene for the largest subunit of DdRP was localized within the DNA sequences of a part of the BamHI DNA fragment A (BamHI/HindIII DNA fragment A8a; 13.5 kbp, 0.454 to 0.525 viral map units) of the MCV-1 genome. The DNA nucleotide sequence analysis of a part (6709 bp) of this DNA fragment revealed the presence of 12 open reading frames (ORFs). It was found that ORF-4 (nucleotide position (NP) 2586 to 6452) and ORF-1 (NP 1192 to 1752) encode two polypeptides comprising 1289 (147 kDa) and 187 (22 kDa) amino acid residues, respectively. The comparative analysis of the amino acid sequences of these ORFs to the amino acid sequences of two subunits (RPO1, 147 kDa and RPO6, 22 kDa) of the DdRP of vaccinia virus revealed high amino acid sequence identity/similarity of about 71.9/21.5% and 46.5/39.6%, respectively. In addition it was found that the putative gene position of ORF-11, which is located on the lower strand between the loci of the ORF-1 and ORF-4 (NP 4256 to 4657, 134 aa, 15 kDa), is similar to the genomic arrangement of the J5L protein of vaccinia virus and L5L of variola virus. The value of amino acid sequence identity/similarity between the product of ORF-11 and the corresponding gene of vaccinia virus (J5L) was found to be 43.2/28.8%. The analysis of the amino acid sequence deduced from ORF-3 (NP 261 to 1289, 343 aa, 40 kDa), which is located upstream from the locus of the RPO6 of the MCV-1 genome, showed significant identity/similarity (47.5/35.7%) to the amino acid sequence of the 40-kDa subunit of the poly(A) polymerase (PAP2) of vaccinia virus. The arrangement of the identified loci of the PAP2, RPO6, ORF-11, and RPO1 of the genome of MCV-1 shows that this particular genomic region of the mollucsum contagiosum virus and vaccina virus is colinear.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/genética , Genes Virales/genética , Virus del Molusco Contagioso/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ARN Polimerasas Dirigidas por ADN/química , Datos de Secuencia Molecular , Virus del Molusco Contagioso/enzimología , Sistemas de Lectura Abierta/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
15.
Virology ; 233(1): 19-42, 1997 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-9201214

RESUMEN

Analysis of the molluscum contagiosum virus (MCV) genome revealed that it encodes approximately 182 proteins, 105 of which have direct counterparts in orthopoxviruses (OPV). The corresponding OPV proteins comprise those known to be essential for replication as well as many that are still uncharacterized, including 2 of less than 60 amino acids that had not been previously noted. The OPV proteins most highly conserved in MCV are involved in transcription; the least conserved include membrane glycoproteins. Twenty of the MCV proteins with OPV counterparts also have cellular homologs and additional MCV proteins have conserved functional motifs. Of the 77 predicted MCV proteins without OPV counterparts, 10 have similarity to other MCV proteins and/or distant similarity to proteins of other poxviruses and 16 have cellular homologs including some predicted to antagonize host defenses. Clustering poxvirus proteins by sequence similarity revealed 3 unique MCV gene families and 8 families that are conserved in MCV and OPV. Two unique families contain putative membrane receptors; the third includes 2 proteins, each containing 2 DED apoptosis signal transduction domains. Additional families with conserved patterns of cysteines and putative redox active centers were identified. Promoters, transcription termination signals, and DNA concatemer resolution sequences are highly conserved in MCV and OPV. Phylogenetic analysis suggested that MCV, OPV, and leporipoxviruses radiated from a common poxvirus ancestor after the divergence of avipoxviruses. Despite the acquisition of unique genes for host interactions and changes in GC content, the physical order and regulation of essential ancestral poxvirus genes have been largely conserved in MCV and OPV.


Asunto(s)
Genoma Viral , Virus del Molusco Contagioso/genética , Secuencia de Aminoácidos , Animales , Apoptosis , Secuencia de Bases , Células , Secuencia de Consenso , Secuencia Conservada , ADN Viral , Genes Virales , Humanos , Cuerpos de Inclusión Viral , Datos de Secuencia Molecular , Virus del Molusco Contagioso/clasificación , Sistemas de Lectura Abierta , Oxidación-Reducción , Filogenia , Poxviridae/genética , Regiones Promotoras Genéticas , Homología de Secuencia de Aminoácido , Transcripción Genética , Proteínas Virales/análisis
16.
Virus Genes ; 20(1): 35-45, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10766305

RESUMEN

In 1997 TTV was detected using representational difference analysis (RDA) in serum of a patient with posttransfusion hepatitis unrelated to known hepatitis viruses. The genome of TTV is a circular single-stranded DNA molecule of 3852 nt with negative polarity. TTV possibly can be grouped either into the existing family Circoviridae or into a recently established virus family "Circinoviridae". Analysis of the complete DNA nucleotide sequence of TTV identified three partially overlapping open reading frames (ORFs). Neither DNA nucleotide nor corresponding amino acid sequences of TTV do show significant homologies to known sequences. TTV DNA nucleotide sequences amplified by PCR from sera of different patients show considerable sequence variations. Although the natural route of transmission of TTV is still unknown, there is clear evidence for a transmission of TTV through blood and blood products. TTV DNA can be detected in the feces of infected individuals suggesting that it may be possible to attract TTV infection from environmental sources. Since the discovery of TTV, numerous studies have investigated the prevalence of TTV infections in different human population groups all over the world. All these studies are based on PCR detection systems, but the technical aspects of the PCR systems vary significantly between the different investigators. The results of the epidemiological studies do not show a clear picture. The discovery of TTV as a viral agent and particularly the identification of a high percentage of infected carriers in the healthy human population raises the following questions: Firstly, what is the origin and molecular relatedness of TT virus. Secondly, what is the significance of TTV as a human pathogen. And thirdly, what are the exact molecular mechanisms of viral replication. To answer these questions it will be necessary to determine the primary structure and the coding capacity of several TTV patient isolates.


Asunto(s)
Circoviridae/genética , Genoma Viral , Animales , Secuencia de Bases , Circoviridae/clasificación , Circoviridae/patogenicidad , Infecciones por Circoviridae/transmisión , Variación Genética , Humanos , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico
17.
Virology ; 242(1): 51-9, 1998 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-9501046

RESUMEN

An analysis of the complete Molluscum contagiosum virus (MCV-1) genome sequence revealed a 104-amino-acid open reading frame (MC148R) that is structurally related to the beta (CC) family of chemokines. The predicted MCV chemokine homolog (MCCH) has a deletion in the NH2-terminal activation domain, suggesting the absence of chemoattractant activity. The principal objectives of the present study were to determine whether: (i) MCCH is conserved in independent isolates of MCV-1 and MCV-2; (ii) MCCH mRNA is expressed in vivo; and (iii) the MCCH protein is secreted from mammalian cells. The nucleotide sequence of the MCCH gene locus was determined for 27 isolates of MCV-1 and 2 of MCV-2 obtained from 29 MCV-infected individuals. In each case, the characteristic CC sequence, the NH2-terminal deletion, and the length of the open reading frame were conserved, although there were some, mostly conservative, amino acid substitutions. Since MCV cannot be propagated in cell culture, mRNA was synthesized in vitro by the early transcription apparatus in purified MCV virions. MCCH RNA was amplified by RT-PCR; the sequence included the complete open reading frame and extended 40 to 50 nucleotides past the first poxviral termination signal (TTTTTNT). Similar RT-PCR results were obtained using total cellular RNA derived from MCV-infected tissue specimens. Finally, the MCCH open reading frame was expressed in a vaccinia virus vector and the predicted size polypeptide was secreted into the medium, as determined by Western blotting. Taken together, our data support the prediction that MCV expresses a secreted chemokine homolog that could antagonize the inflammatory response in vivo.


Asunto(s)
Quimiocinas CC/química , Quimiocinas CC/genética , Virus del Molusco Contagioso/genética , Sistemas de Lectura Abierta , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Quimiocina CCL4 , Quimiocinas CC/biosíntesis , Vectores Genéticos , Humanos , Cinética , Proteínas Inflamatorias de Macrófagos/química , Datos de Secuencia Molecular , Molusco Contagioso/patología , Molusco Contagioso/virología , Virus del Molusco Contagioso/metabolismo , Reacción en Cadena de la Polimerasa , ARN Mensajero/biosíntesis , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Piel/inmunología , Piel/virología , Transcripción Genética , Virus Vaccinia/genética
18.
J Gen Virol ; 75 ( Pt 7): 1557-67, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8021587

RESUMEN

Cytoplasmic DNA viruses encode a DNA-dependent RNA polymerase (DdRP) that is essential for transcription of viral genes. The amino acid sequences of known large subunits of DdRPs contain highly conserved regions. Oligonucleotide primers, deduced from two conserved domains [RQP(T/S)LH and NADFDGDE] were used in PCR experiments for the detection of the corresponding gene of the genome of insect iridescent virus type 6, also known as Chilo iridescent virus (CIV). A specific DNA product of about 150 bp could be amplified and was used as a hybridization probe against the CIV gene library to identify the corresponding gene. The gene encoding the DdRP was identified within the EcoRI fragments M (7099 bp) and L (7400 bp) of CIV DNA, between map units 0.310 and 0.347 (7990 bp). The DNA nucleotide sequence (3153 bp) of the gene encoding the largest subunit of DdRP (RPO1) was determined. Northern blot hybridization revealed the presence of a 3.4 kb RNA transcript in CIV-infected cells that hybridized to the CIV DdRP gene. This predicted viral protein consists of 1051 amino acid residues (120K) and showed considerably higher similarity to the largest subunit of eukaryotic RNA polymerase II than to the homologous proteins of vaccinia virus and African swine fever virus. Phylogenetic analysis suggested that the putative RPO1 of CIV could have evolved from RNA polymerase II after the divergence of the three types of eukaryotic RNA polymerases. The putative RPO1 of CIV lacked the C-terminal domain that is conserved in eukaryotic, eubacterial and other viral RNA polymerases and in this respect was analogous to the RNA polymerases of Archaea. It is hypothesized that the equivalent of the C-terminal domain may reside in another subunit of CIV DdRP encoded by an unidentified viral gene.


Asunto(s)
Genes Virales/genética , Iridovirus/genética , Filogenia , ARN Polimerasa II/genética , Proteínas Virales/genética , Proteínas Estructurales Virales/genética , Secuencia de Aminoácidos , Secuencia de Bases , Secuencia Conservada , Genoma Viral , Iridovirus/enzimología , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , ARN Polimerasa II/química , ARN Viral/análisis , Mapeo Restrictivo , Alineación de Secuencia , Análisis de Secuencia de ADN , Transcripción Genética , Proteínas Virales/química
19.
Virus Genes ; 7(1): 111-6, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8385838

RESUMEN

A gene was identified within the DNA sequences of the EcoRI DNA fragment N (4.3 kbp) of the genome of equine herpesvirus type 2 (EHV-2) coding for a protein (179 amino acid residues) homologous to the cytokine synthesis inhibitory factor (CSIF; interleukin 10) of the human and mouse, and to the Epstein-Barr virus (EBV) protein BCRF1. This finding is further significant evidence that the interleukin 10 (IL-10) and/or IL-10-like gene can indeed be present in the genomes of members of the herpesviral family.


Asunto(s)
Herpesviridae/genética , Interleucina-10/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ADN Viral/genética , Genes Virales , Herpesvirus Humano 4/genética , Humanos , Ratones , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Proteínas Virales/genética
20.
Virus Genes ; 9(1): 61-75, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7871763

RESUMEN

The complete DNA nucleotide sequence of the EcoRI DNA fragment N (0.235 to 0.258 viral map units) of equine herpes virus type 2 (EHV-2) strain T400/3 was determined. This DNA fragment comprises 4237 bp with a base composition of 55.23% G+C and 44.77% A+T. Nineteen open reading frames (ORFs) of 50-287 amino acid (aa) residues were detected. ORF number 10 is located between the nucleotide position 2220 and 2756 coding for a protein of 179 amino acid residues. This protein shows significant homology to the cytokine synthesis inhibitory factor (CSIF; interleukin 10) of human (76.4%) and mouse (68.5%), and to the Epstein-Barr virus (EBV) protein BCRF1 (70.6%). The existence of an interleukin 10 (IL-10) analogous gene within the genome of the EHV-2 was confirmed by screening the genome of nine EHV-2 strains using specific oligonucleotide primers corresponding to the 5' and 3' region of this particular gene by polymerase chain reaction. In all experiments an 870 bp DNA product was amplified. The specifity of the amplified DNA fragments obtained from individual EHV-2 strains was confirmed by DNA-DNA hybridization experiments. The DNA sequence analysis of the amplified DNA products of the EHV-2 strain LK was carried out. This analysis revealed the identity of the corresponding IL-10 gene (540 bp) of this strain to the IL-10 gene of EHV-2 strain T400/3. The presented data indicate that the EHV-2 genome harbors a viral interleukin 10-like gene. This is further evidence that the IL-10 gene can be present in the genomes of members of the Herpesviridae family.


Asunto(s)
ADN Viral/genética , Genoma Viral , Varicellovirus/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células Cultivadas , Mapeo Cromosómico , Infecciones por Herpesviridae/virología , Caballos , Humanos , Interleucina-10/genética , Ratones , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteínas Virales/genética
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