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1.
Int Urogynecol J ; 24(5): 781-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23001046

RESUMO

INTRODUCTION AND HYPOTHESIS: To evaluate current practice in the surgical treatment of uterine descent among members of the Dutch Urogynecological Society and to analyze possible trends in the surgical treatment of pelvic organ prolapse in the Netherlands during the last decade. METHODS: A questionnaire, including case scenarios, was sent to the members of the Dutch Urogynecological Society. Using a nationwide registry from the Netherlands, we assessed the number and type of surgical procedures performed for pelvic organ prolapse between 1997 and 2009. RESULTS: The response rate was 73%, with 161 questionnaires completed. Vaginal hysterectomy, sacrospinous hysteropexy, and the Manchester Fothergill procedure were the most frequently performed surgical interventions for uterine descent. In the case of lower stage uterine descent, uterus preservation was preferred, but in the case of higher stage there was wide variation. Two thirds of the respondents stated that in recent years they tended to save the uterus more often. The registered number of hospital admissions for uterine descent increased by 30% between 1997 and 2009 and the number of surgical procedures almost doubled. The number of vaginal hysterectomies performed because of uterine descent increased by only 15% in this period. CONCLUSIONS: In the Netherlands, surgical policy in the case of uterine descent is very variable, with no clear preference for either hysterectomy or uterus preservation. There was a high increase in hospital admissions and pelvic organ prolapse procedures in the last decade. The number of vaginal hysterectomies performed because of uterine descent did not follow this change, which reflects a trend toward preserving the uterus.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/estatística & dados numéricos , Prolapso de Órgão Pélvico/cirurgia , Sistema de Registros , Feminino , Ginecologia/estatística & dados numéricos , Humanos , Masculino , Países Baixos , Prolapso de Órgão Pélvico/diagnóstico , Cuidados Pré-Operatórios , Urologia/estatística & dados numéricos , Útero
2.
Ned Tijdschr Geneeskd ; 149(11): 577-82, 2005 Mar 12.
Artigo em Holandês | MEDLINE | ID: mdl-15799640

RESUMO

In the year 2004 there were an estimated 220,000-320,000 people in The Netherlands with visual impairment. In 150,000-220,000 (70%) of them the visual impairment is either curable or could have been prevented. Those most at risk are people with intellectual disabilities, elderly people in care institutions, elderly people in general and diabetics. 'Vision 2020 Netherlands', an initiative of the World Health Organization, was launched to eliminate avoidable visual impairment in the Netherlands by the year 2020 by means of awareness campaigns, implementation of screening programmes and by expanding eye care capacity through efficient cooperation between the professional groups involved in eye care.


Assuntos
Transtornos da Visão/prevenção & controle , Promoção da Saúde , Humanos , Programas de Rastreamento , Países Baixos/epidemiologia , Fatores de Risco , Transtornos da Visão/epidemiologia , Organização Mundial da Saúde
3.
J Virol ; 75(24): 12370-81, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11711627

RESUMO

RNA replication of all positive-strand RNA viruses is closely associated with intracellular membranes. Brome mosaic virus (BMV) RNA replication occurs on the perinuclear region of the endoplasmic reticulum (ER), both in its natural plant host and in the yeast Saccharomyces cerevisiae. The only viral component in the BMV RNA replication complex that localizes independently to the ER is 1a, a multifunctional protein with an N-terminal RNA capping domain and a C-terminal helicase-like domain. The other viral replication components, the RNA polymerase-like protein 2a and the RNA template, depend on 1a for recruitment to the ER. We show here that, in membrane extracts, 1a is fully susceptible to proteolytic digestion in the absence of detergent and thus, a finding consistent with its roles in RNA replication, is wholly or predominantly on the cytoplasmic face of the ER with no detectable lumenal protrusions. Nevertheless, 1a association with membranes is resistant to high-salt and high-pH treatments that release most peripheral membrane proteins. Membrane flotation gradient analysis of 1a deletion variants and 1a segments fused to green fluorescent protein (GFP) showed that sequences in the N-terminal RNA capping module of 1a mediate membrane association. In particular, a region C-terminal to the core methyltransferase homology was sufficient for high-affinity ER membrane association. Confocal immunofluorescence microscopy showed that even though these determinants mediate ER localization, they fail to localize GFP to the narrow region of the perinuclear ER, where full-length 1a normally resides. Instead, they mediate a more globular or convoluted distribution of ER markers. Thus, additional sequences in 1a that are distinct from the primary membrane association determinants contribute to 1a's normal subcellular distribution, possibly through effects on 1a conformation, orientation, or multimerization on the membrane.


Assuntos
Bromovirus/enzimologia , Retículo Endoplasmático/metabolismo , RNA Polimerase Dependente de RNA/química , Bromovirus/genética , Membrana Celular/metabolismo , Proteínas de Fluorescência Verde , Concentração de Íons de Hidrogênio , Proteínas Luminescentes/análise , RNA Viral/biossíntese , RNA Polimerase Dependente de RNA/metabolismo
4.
J Virol ; 74(19): 8803-11, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10982322

RESUMO

Brome mosaic virus (BMV) encodes two RNA replication proteins: 1a, which contains RNA capping and helicase-like domains, and 2a, which is related to polymerases. BMV 1a and 2a can direct virus-specific RNA replication in the yeast Saccharomyces cerevisiae, which reproduces the known features of BMV replication in plant cells. We constructed single amino acid point mutations at the predicted capping and helicase active sites of 1a and analyzed their effects on BMV RNA3 replication in yeast. The helicase mutants showed no function in any assays used: they were strongly defective in template recruitment for RNA replication, as measured by 1a-induced stabilization of RNA3, and they synthesized no detectable negative-strand or subgenomic RNA. Capping domain mutants divided into two groups. The first exhibited increased template recruitment but nevertheless allowed only low levels of negative-strand and subgenomic mRNA synthesis. The second was strongly defective in template recruitment, made very low levels of negative strands, and made no detectable subgenomes. To distinguish between RNA synthesis and capping defects, we deleted chromosomal gene XRN1, encoding the major exonuclease that degrades uncapped mRNAs. XRN1 deletion suppressed the second but not the first group of capping mutants, allowing synthesis and accumulation of large amounts of uncapped subgenomic mRNAs, thus providing direct evidence for the importance of the viral RNA capping function. The helicase and capping enzyme mutants showed no complementation. Instead, at high levels of expression, a helicase mutant dominantly interfered with the function of the wild-type protein. These results are discussed in relation to the interconnected functions required for different steps of positive-strand RNA virus replication.


Assuntos
Bromovirus/fisiologia , RNA Viral/genética , Proteínas Virais/genética , Replicação Viral/genética , Regulação Viral da Expressão Gênica , Saccharomyces cerevisiae/virologia
5.
Hum Reprod ; 14(9): 2402-3, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10469720

RESUMO

We describe a very late manifestation of pelvic abscesses after oocyte retrieval for in-vitro fertilization (IVF). In a twin pregnancy achieved after intracytoplasmic sperm injection, rupture of bilateral ovarian abscesses occurred at the end of the second trimester. An emergency laparotomy was necessary because of an acute abdomen. This complication led to severe maternal and neonatal morbidity, preterm birth and neonatal death. The rare occurrence of acute abdomen in pregnancy due to pelvic infection and the non-specific symptoms of a pelvic abscess after oocyte retrieval for IVF are discussed.


Assuntos
Abscesso/diagnóstico , Fertilização in vitro/efeitos adversos , Doenças Ovarianas/diagnóstico , Abdome Agudo/microbiologia , Abscesso/etiologia , Abscesso/cirurgia , Adulto , Tratamento de Emergência , Evolução Fatal , Feminino , Humanos , Laparotomia , Masculino , Trabalho de Parto Prematuro , Doenças Ovarianas/etiologia , Doenças Ovarianas/cirurgia , Gravidez , Edema Pulmonar/cirurgia , Infecções Estafilocócicas/diagnóstico
6.
Eur J Gynaecol Oncol ; 20(3): 187-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10410881

RESUMO

Malignant change to glioblastoma multiforme in a mature cystic teratoma (dermoid cyst) is exceptionally rare. Besides a report on such a case we give a brief review of the literature on this subject and a comment on treatment. The reported case is about a 41-year-old woman with a mature cystic teratoma of the ovary with transformation to glioblastoma multiform. The tumor was limited to the ovary and completely excised by salpingo-oophorectomy. Three and a half years after surgery the patient is alive without evidence of recurrent disease. For limited stage Ia tumors we found support in the literature for expectant management after surgery, without adjuvant chemotherapy.


Assuntos
Glioblastoma/patologia , Neoplasias Ovarianas/patologia , Adulto , Feminino , Glioblastoma/cirurgia , Humanos , Neoplasias Ovarianas/cirurgia , Ovariectomia , Salpingostomia
7.
Proc Natl Acad Sci U S A ; 94(3): 991-6, 1997 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-9023370

RESUMO

Equine arteritis virus (EAV) is a positive-strand RNA virus that uses a discontinuous transcription mechanism to generate a nested set of six subgenomic mRNAs from which its structural genes are expressed. A stable bacterial plasmid (pEAV030) containing a full-length cDNA copy of the 12.7-kb EAV genome was constructed. After removal of a single point mutation in the replicase gene, RNA transcripts generated in vitro from pEAV030 were shown to be infectious upon electroporation into BHK-21 cells. A genetic marker mutation was introduced at the cDNA level and recovered from the genome of the progeny virus. The potential of pEAV030 as a tool to express foreign genes was demonstrated by the efficient expression of the chloramphenicol acetyltransferase (CAT) reporter gene from two different subgenomic mRNAs. The point mutation that initially rendered the full-length clone noninfectious was found to result in a particularly intriguing phenotype: RNA carrying this mutation can replicate efficiently but does not produce the subgenomic mRNAs required for structural protein expression. To our knowledge, this mutant provides the first evidence that the requirements for arterivirus genome replication and discontinuous mRNA synthesis are, at least partially, different and that these processes may be separated experimentally.


Assuntos
DNA Complementar/genética , Equartevirus/genética , Regulação Viral da Expressão Gênica/genética , Mutação Puntual , RNA Polimerase Dependente de RNA/genética , Animais , Linhagem Celular , Clonagem Molecular , Cricetinae , Equartevirus/enzimologia , Vetores Genéticos , Rim , Dados de Sequência Molecular , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Viral/biossíntese , RNA Viral/genética , Transcrição Gênica/genética , Replicação Viral
8.
J Cataract Refract Surg ; 22(9): 1159-64, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8972366

RESUMO

PURPOSE: To evaluate the safety and efficacy of a photorefractive keratectomy (PRK) re-treatment procedure that enlarges the optical zone and treats undercorrection. SETTING: Rotterdam Eye Hospital and Medisch Centrum Alkmaar, The Netherlands. METHODS: This study evaluated 16 eyes that had PRK for myopia with the Summit excimer laser that resulted in a mean undercorrection of -2.82 diopters (D). Patients also reported impaired night vision including difficulty in driving, halos, and stray light and ghost images. These phenomena persisted after spectacle correction of residual refractive error, necessitating further treatment with a larger ablation zone. With a VISX 20/20 excimer laser, the optical zone was enlarged to 6.0 mm and undercorrection treated with a 6.0 mm ablation. RESULTS: At 13.5 months after re-treatment, mean reduction in myopia was 1.70 D, resulting in a residual undercorrection of -1.08 D. In seven eyes, final refraction was within 1.00 D of emmetropia. Only two patients continued to report night-driving problems. CONCLUSIONS: Re-treating undercorrections combined with enlarging the ablation zone resulted in a reduction in myopia from a mean of 2.82 to 1.08 D. Subjective reports of halos and stray light images were decreased in all cases.


Assuntos
Córnea/fisiologia , Córnea/cirurgia , Miopia/cirurgia , Ceratectomia Fotorrefrativa , Adulto , Feminino , Ofuscação , Humanos , Processamento de Imagem Assistida por Computador , Lasers de Excimer , Masculino , Miopia/fisiopatologia , Refração Ocular , Reoperação , Segurança , Resultado do Tratamento , Acuidade Visual
9.
J Virol ; 70(7): 4291-8, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8676451

RESUMO

In addition to the genomic RNA, a 3' coterminal nested set of six subgenomic mRNAs is produced in equine arteritis virus (EAV)-infected cells. The seven viral RNAs are also 5' coterminal, since they all contain a 206-nucleotide common leader sequence which is identical to the 5' end of the genome. A conserved penta-nucleotide sequence motif, 5' UCAAC 3', was shown to be present at the junctions between the leader and body sequences in each of the mRNAs. In addition, two alternative junction sites were detected for mRNA 3. Seven replicative-form (RF) RNAs (RFs I to VII), corresponding to the genomic RNA and each of the subgenomic EAV mRNAs, could be prepared from lysates of infected cells. The minus-strand RNA contents of these RF RNAs were analyzed by using an RNase protection assay with an RNA probe containing the mRNA 2 leader-body junction. It was established that RF II contained a negative-stranded copy of mRNA 2, including a complementary leader sequence. The presence of subgenomic minus-strand RNA in RFs is indicative of a function as a transcription template during the production of EAV subgenomic mRNAs.


Assuntos
Equartevirus/genética , RNA Mensageiro/biossíntese , RNA Viral/biossíntese , Animais , Sequência de Bases , Linhagem Celular , Sequência Conservada , Cricetinae , Genoma Viral , Dados de Sequência Molecular , Sondas de Oligonucleotídeos
10.
Virology ; 213(2): 364-72, 1995 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-7491761

RESUMO

The expression of the genetic information of equine arteritis virus (EAV), an arterivirus, involves the synthesis of six subgenomic (sg) mRNAs. These are 5' and 3' coterminal since they are composed of a leader and a body sequence, which are identical to the 5' and 3' ends of the genome, respectively. Previously, it has been suggested that cis-splicing of a genome-length precursor RNA is involved in their synthesis. This was reevaluated in a comparative analysis of the sg RNA synthesis of EAV, the coronavirus mouse hepatitis virus (MHV), and the alphavirus Sindbis virus. UV transcription mapping showed that the majority of the EAV sg RNAs made at later stages of infection is not derived from a genome-length precursor. However, complete independence of sg RNA synthesis from that of genomic RNA was never observed during the course of infection. The possibility that this resulted from UV irradiation-induced effects on the synthesis of the viral replicase was investigated by inhibiting translation using cycloheximide. For EAV, ongoing protein synthesis was found to be more important for the synthesis of sg RNA than for that of genomic RNA. In general, MHV transcription was extremely sensitive to translation inhibition, whereas EAV genomic RNA synthesis became independent of de novo protein synthesis late in infection.


Assuntos
Equartevirus/genética , Biossíntese de Proteínas , RNA Mensageiro/biossíntese , RNA Viral/biossíntese , RNA Polimerase Dependente de RNA/biossíntese , Transcrição Gênica , Proteínas Virais/biossíntese , Animais , Linhagem Celular , Cicloeximida/farmacologia , Equartevirus/fisiologia , Equartevirus/efeitos da radiação , Genoma Viral , Camundongos , Vírus da Hepatite Murina/genética , Vírus da Hepatite Murina/efeitos da radiação , Inibidores da Síntese de Proteínas/farmacologia , Precursores de RNA/metabolismo , RNA Viral/genética , RNA Viral/efeitos da radiação , Sindbis virus/genética , Sindbis virus/efeitos da radiação , Raios Ultravioleta
11.
J Virol ; 69(7): 4500-5, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7769711

RESUMO

Two adjacent papainlike cysteine protease (PCP) domains, PCP alpha and PCP beta, were identified in the N-terminal region of the open reading frame 1a replicase proteins of the arteriviruses porcine reproductive and respiratory syndrome virus and lactate dehydrogenase-elevating virus. The replicase of the related virus equine arteritis virus contains only one active PCP in the corresponding region. Sequence comparison revealed that the equine arteritis virus PCP alpha counterpart probably was inactivated by loss of its catalytic Cys residue. For both porcine reproductive and respiratory syndrome virus and lactate dehydrogenase-elevating virus, the generation of two processing products, nsp1 alpha and nsp1 beta, was demonstrated by in vitro translation. Site-directed mutagenesis and sequence comparison were used to identify the putative active-site residues of the PCP alpha and PCP beta protease domains and to show that they mediate the nsp1 alpha/1 beta and nsp1 beta/2 cleavages, respectively.


Assuntos
Arterivirus/enzimologia , Fases de Leitura Aberta , Papaína/análise , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Arterivirus/genética , Sítios de Ligação , Dados de Sequência Molecular , Papaína/química , RNA Polimerase Dependente de RNA/genética
14.
J Cell Physiol ; 149(1): 44-9, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1939346

RESUMO

In this paper we show that in C3H10T1/2 mouse fibroblasts, the inducibility of c-fos mRNA by heat shock or serum addition is strongly dependent on the cell's past. Four hours after a heat shock, a time point where the induced c-fos mRNA has disappeared, c-fos mRNA could not be induced again by a second heat shock. Four hours after serum addition, by which c-fos was induced, a second serum addition also failed to induce c-fos mRNA again. When, however, serum was added 4 hours after heat shock or heat shock was given 4 hours after serum addition, levels of c-fos mRNA could be enhanced again. The induction by serum of c-fos mRNA levels in thermotolerant cells might be related to their increased stimulation of DNA synthesis as compared to control cells.


Assuntos
Regulação da Expressão Gênica , Genes fos , RNA Mensageiro/genética , Animais , Sangue , Linhagem Celular , Meios de Cultura , Temperatura Alta , Interfase , Camundongos , Biossíntese de Proteínas , RNA Mensageiro/metabolismo
15.
J Gen Virol ; 72 ( Pt 7): 1635-43, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1856694

RESUMO

Defective interfering (DI) RNAs of Berne virus (BEV) were generated by serial undiluted passaging of the virus in embryonic mule skin cells. Two DI RNAs of 1.0 and 1.4 kb (designated DI1000 and DI1400) were characterized in more detail. Isokinetic sucrose gradient analysis showed that these DI RNAs are specifically packaged into particles with smaller S values than standard virions. Both DI RNAs were cloned and sequenced. Three genomic cDNA clones were identified using probes complementary to the 5' end of a DI RNA, which are thought to be derived from the 5'-terminal region of the BEV genome. A non-translated region of about 700 nt and the 5' end of the putative BEV replicase gene were identified in the consensus nucleotide sequence. Both DI RNAs were shown to contain sequences from the 5' and 3' ends of the BEV genome. A conserved sequence motif, which has been postulated to be involved in sub-genomic RNA transcription, was also identified just downstream of the extreme 5' ends of DI1000 and DI1400.


Assuntos
Vírus Defeituosos/genética , Vírus de RNA/genética , RNA Viral/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Linhagem Celular , Centrifugação com Gradiente de Concentração , Clonagem Molecular , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Regiões Promotoras Genéticas , RNA Viral/análise , RNA Viral/biossíntese , Inoculações Seriadas
16.
Virology ; 182(2): 655-63, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2024492

RESUMO

The nucleotide sequence of the Berne virus envelope (E) protein gene was determined and its 26.5K translation product was identified by in vitro transcription and translation. Computer analysis of the protein sequence revealed the characteristics of a class III membrane protein lacking a cleaved signal sequence but containing three successive transmembrane alpha-helices in the N-terminal half, much the same as the coronavirus membrane (M) protein. The disposition of the E protein in the membrane was studied by in vitro translation in the presence of microsomes and by subsequent proteinase K digestion. Only small portions of either end of the polypeptide were found to be exposed on opposite sides of the vesicle membranes. Experiments with a hybrid E protein (EM) containing the C-terminal tail of a coronavirus M protein, to which an anti-peptide serum was available, showed that this C-terminus was present at the cytoplasmic side of the membrane, which is another similarity to the coronavirus M protein. Immunofluorescence experiments indicated that the EM protein, expressed by a recombinant vaccinia virus, accumulated in intracellular membranes, predominantly those of the endoplasmic reticulum. The common features of the torovirus E and the coronavirus M protein support our hypothesis that an evolutionary relationship exists between these groups of intracellularly budding viruses.


Assuntos
Vírus de RNA/genética , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Transporte Biológico , Compartimento Celular , Linhagem Celular , Chlorocebus aethiops , Clonagem Molecular , DNA/genética , Genes Virais , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/ultraestrutura , Dados de Sequência Molecular , Peso Molecular , Vírus de RNA/análise , RNA Viral/genética , Termodinâmica , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo , Proteínas do Envelope Viral/ultraestrutura , Proteínas Estruturais Virais/genética
17.
J Virol ; 65(6): 2910-20, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1851863

RESUMO

The nucleotide sequence of the genome of equine arteritis virus (EAV) was determined from a set of overlapping cDNA clones and was found to contain eight open reading frames (ORFs). ORFs 2 through 7 are expressed from six 3'-coterminal subgenomic mRNAs, which are transcribed from the 3'-terminal quarter of the viral genome. A number of these ORFs are predicted to encode structural EAV proteins. The organization and expression of the 3' part of the EAV genome are remarkably similar to those of coronaviruses and toroviruses. The 5'-terminal three-quarters of the genome contain the putative EAV polymerase gene, which also shares a number of features with the corresponding gene of corona- and toroviruses. The gene contains two large ORFs, ORF1a and ORF1b, with an overlap region of 19 nucleotides. The presence of a "shifty" heptanucleotide sequence in this region and a downstream RNA pseudoknot structure indicate that ORF1b is probably expressed by ribosomal frameshifting. The frameshift-directing potential of the ORF1a/ORF1b overlap region was demonstrated by using a reporter gene. Moreover, the predicted ORF1b product was found to contain four domains which have been identified in the same relative positions in coronavirus and torovirus ORF1b products. The sequences of the EAV and coronavirus ORF1a proteins were found to be much more diverged. The EAV ORF1a product contains a putative trypsinlike serine protease motif. Our data indicate that EAV, presently considered a togavirus, is evolutionarily related to viruses from the coronaviruslike superfamily.


Assuntos
Coronaviridae/genética , Equartevirus/genética , Replicação Viral , Sequência de Aminoácidos , Sequência de Bases , Evolução Biológica , DNA Viral/química , RNA Polimerases Dirigidas por DNA/genética , Equartevirus/crescimento & desenvolvimento , Expressão Gênica , Células HeLa/microbiologia , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta , RNA Mensageiro/biossíntese , Ribossomos/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/genética , Togaviridae/genética , Vírion/genética
18.
Virology ; 180(1): 448-52, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1984666

RESUMO

Recently, toroviruses and coronaviruses have been found to be ancestrally related by divergence of their polymerase and envelope proteins from common ancestors. In addition, their genome organization and expression strategy, which involves the synthesis of a 3'-coterminal nested set of mRNAs, are comparable. Nucleotide sequence analysis of the genome of the torovirus prototype, Berne virus (BEV), has now revealed the results of two independent nonhomologous RNA recombinations during torovirus evolution. Berne virus open reading frame (ORF) 4 encodes a protein with significant sequence similarity (30-35% identical residues) to a part of the hemagglutinin esterase proteins of coronaviruses and influenza virus C. The sequence of the C-terminal part of the predicted BEV polymerase ORF1a product contains 31-36% identical amino acids when compared with the sequence of a nonstructural 30/32K coronavirus protein. The cluster of coronaviruses which contains this nonstructural gene expresses it not as a part of their polymerase, but by synthesizing an additional subgenomic mRNA.


Assuntos
Evolução Biológica , Coronaviridae/genética , Vírus de RNA/genética , RNA Viral/genética , Recombinação Genética , Sequência de Aminoácidos , Sequência de Bases , Coronaviridae/classificação , DNA Viral , Genes Virais , Dados de Sequência Molecular , Fases de Leitura Aberta , Vírus de RNA/classificação , Homologia de Sequência do Ácido Nucleico , Proteínas Virais/genética
19.
Virology ; 178(2): 355-63, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2219698

RESUMO

The nucleotide sequence of the peplomer (P) protein gene of Berne virus (BEV), the torovirus prototype, was determined. The gene encodes an apoprotein of 1581 amino acids with an Mr of about 178K. The open reading frame was cloned behind the T7 RNA polymerase promoter and its translation product was identified as the BEV P protein precursor by in vivo expression and immunoprecipitation. The deduced amino acid sequence contains a number of domains which are typical for type I membrane glycoproteins: an N-terminal signal sequence, a putative C-terminal transmembrane anchor, and a cytoplasmic tail. Eighteen potential N-glycosylation sites, two heptad repeat domains, and a possible "trypsin-like" cleavage site were identified. The mature P protein consists of two subunits and their electrophoretic mobility upon endoglycosidase F treatment strongly suggests that the predicted cleavage site is functional in vivo. The heptad repeat domains are probably involved in the generation of an intra-chain coiled-coil secondary structure; similar inter-chain interactions can play a role in P protein oligomerization. Using a sucrose gradient assay the P protein was indeed shown to form dimers. The intra- and inter-chain coiled-coil interactions may stabilize the elongated BEV peplomers.


Assuntos
Fases de Leitura Aberta , Precursores de Proteínas/genética , Processamento de Proteína Pós-Traducional , Vírus de RNA/genética , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Viral/biossíntese , Células HeLa , Humanos , Hidrólise , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Conformação Proteica , Precursores de Proteínas/biossíntese , Sequências Repetitivas de Ácido Nucleico , Mapeamento por Restrição
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