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1.
Zootaxa ; 4852(3): zootaxa.4852.3.7, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-33056417

RESUMO

A new species of Neotropical spittlebug (Hemiptera: Cercopoidea: Clastopteridae), Paraclastoptera erwini sp. n., is described and illustrated from Orellana, Ecuador. This species exhibits unique features differentiating it from all known Clastoptera and serves as the genotype for a new genus Paraclastoptera gen. n. This is the second extant New World genus for the Clastopteridae, hitherto represented solely by the widespread, abundant and speciose genus Clastoptera.


Assuntos
Hemípteros , Animais
2.
J Virol ; 91(22)2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28835501

RESUMO

The genomes of human herpesvirus 6A (HHV-6A) and HHV-6B have the capacity to integrate into telomeres, the essential capping structures of chromosomes that play roles in cancer and ageing. About 1% of people worldwide are carriers of chromosomally integrated HHV-6 (ciHHV-6), which is inherited as a genetic trait. Understanding the consequences of integration for the evolution of the viral genome, for the telomere, and for the risk of disease associated with carrier status is hampered by a lack of knowledge about ciHHV-6 genomes. Here, we report an analysis of 28 ciHHV-6 genomes and show that they are significantly divergent from the few modern nonintegrated HHV-6 strains for which complete sequences are currently available. In addition, ciHHV-6B genomes in Europeans are more closely related to each other than to ciHHV-6B genomes from China and Pakistan, suggesting regional variation of the trait. Remarkably, at least one group of European ciHHV-6B carriers has inherited the same ciHHV-6B genome, integrated in the same telomere allele, from a common ancestor estimated to have existed 24,500 ± 10,600 years ago. Despite the antiquity of some, and possibly most, germ line HHV-6 integrations, the majority of ciHHV-6B (95%) and ciHHV-6A (72%) genomes contain a full set of intact viral genes and therefore appear to have the capacity for viral gene expression and full reactivation.IMPORTANCE Inheritance of HHV-6A or HHV-6B integrated into a telomere occurs at a low frequency in most populations studied to date, but its characteristics are poorly understood. However, stratification of ciHHV-6 carriers in modern populations due to common ancestry is an important consideration for genome-wide association studies that aim to identify disease risks for these people. Here, we present full sequence analysis of 28 ciHHV-6 genomes and show that ciHHV-6B in many carriers with European ancestry most likely originated from ancient integration events in a small number of ancestors. We propose that ancient ancestral origins for ciHHV-6A and ciHHV-6B are also likely in other populations. Moreover, despite their antiquity, all of the ciHHV-6 genomes appear to retain the capacity to express viral genes, and most are predicted to be capable of full viral reactivation. These discoveries represent potentially important considerations in immunocompromised patients, in particular in organ transplantation and in stem cell therapy.


Assuntos
Cromossomos Humanos , Genoma Humano , Herpesvirus Humano 6/genética , Característica Quantitativa Herdável , Telômero , Integração Viral/genética , Cromossomos Humanos/genética , Cromossomos Humanos/virologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Telômero/genética , Telômero/virologia
3.
Sci Rep ; 6: 22730, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26947392

RESUMO

Primary effusion lymphomas (PEL) are associated with human herpesvirus-8 (HHV-8) and usually occur in immunocompromised individuals. However, there are numerous reports of HHV-8-unrelated PEL-like lymphomas with unknown aetiology. Here we characterize an HHV-8-unrelated PEL-like lymphoma in an elderly woman who was negative for human immunodeficiency viruses 1 and 2, and hepatitis B and C. The woman was, however, a carrier of an inherited-chromosomally-integrated human herpesvirus-6A (iciHHV-6A) genome in one 19q telomere. The iciHHV-6A genome was complete in blood DNA, encoding a full set of protein-coding genes. Interestingly, the entire iciHHV-6A genome was absent from the HHV-8-unrelated-PEL-like lymphoma cells despite retention of both copies of chromosome 19. The somatic loss of the 19q-iciHHV-6A genome occurred very early during lymphoma development and we propose it occurred via telomere-loop formation and excision to release a circular viral genome that was subsequently lost. Whether release of the HHV-6A genome from the telomere contributed to lymphomagenesis, or was coincidental, remains unclear but this event may have deregulated the expression of HHV-6A or 19q genes or else disrupted telomere function. To establish the frequency and importance of iciHHV-6 loss from telomeres, the HHV-6 copy number should be assessed in tumours that arise in iciHHV-6 carriers.


Assuntos
Cromossomos Humanos Par 19 , Herpesvirus Humano 6/genética , Linfoma de Efusão Primária/diagnóstico , Provírus/genética , Infecções por Roseolovirus/complicações , Deleção de Sequência , Telômero , Idoso , Feminino , Humanos , Linfoma de Efusão Primária/patologia , Linfoma de Efusão Primária/virologia , Masculino , Análise de Sequência de DNA , Integração Viral
4.
J Biol Chem ; 290(30): 18429-37, 2015 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-26055710

RESUMO

Styrene-maleic acid copolymer was used to effect a non-detergent partial solubilization of thylakoids from spinach. A high density membrane fraction, which was not solubilized by the copolymer, was isolated and was highly enriched in the Photosystem (PS) I-light-harvesting chlorophyll (LHC) II supercomplex and depleted of PS II, the cytochrome b6/f complex, and ATP synthase. The LHC II associated with the supercomplex appeared to be energetically coupled to PS I based on 77 K fluorescence, P700 photooxidation, and PS I electron transport light saturation experiments. The chlorophyll (Chl) a/b ratio of the PS I-LHC II membranes was 3.2 ± 0.9, indicating that on average, three LHC II trimers may associate with each PS I. The implication of these findings within the context of higher plant PS I antenna organization is discussed.


Assuntos
Cloroplastos/química , Complexo Citocromos b6f/isolamento & purificação , Complexos de Proteínas Captadores de Luz/isolamento & purificação , Fotossíntese , Complexo de Proteína do Fotossistema I/química , Complexo de Proteína do Fotossistema II/química , Membrana Celular/química , ATPases de Cloroplastos Translocadoras de Prótons/química , Complexo Citocromos b6f/química , Luz , Complexos de Proteínas Captadores de Luz/química , Anidridos Maleicos/química , Complexo de Proteína do Fotossistema I/isolamento & purificação , Complexo de Proteína do Fotossistema II/isolamento & purificação , Poliestirenos/química , Espectrometria de Fluorescência , Spinacia oleracea/química , Tilacoides/química
5.
J Gen Virol ; 96(Pt 7): 1863-72, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25722346

RESUMO

Lymphoma is the most common haematopoietic malignancy in dogs, but little is known about the aetiology of this heterogeneous group of cancers. In humans, the Epstein-Barr virus (EBV) is associated with several lymphoma subtypes. Recently, it was suggested that EBV or an EBV-like virus is circulating in dogs. We therefore investigated whether EBV, or a novel herpesvirus, is associated with canine lymphoma using both serological and molecular techniques. In an assay designed to detect antibodies to EBV viral capsid antigens, 41 % of dogs were positive. Dogs with cancers, including lymphoma, were more frequently positive than controls, but no particular association with B-cell lymphoma was noted. EBV-specific RNA and DNA sequences were not detected in lymphoma tissue by in situ hybridization or PCR, and herpesvirus genomes were not detected using multiple degenerate PCR assays with the ability to detect novel herpesviruses. We therefore found no evidence that herpesviruses are directly involved in common types of canine lymphoma although cannot exclude the presence of an EBV-like virus in the canine population.


Assuntos
Doenças do Cão/virologia , Gammaherpesvirinae/isolamento & purificação , Linfoma/veterinária , Animais , Anticorpos Antivirais/sangue , DNA Viral/isolamento & purificação , Cães , Gammaherpesvirinae/genética , Gammaherpesvirinae/imunologia , Hibridização In Situ , Linfoma/etiologia , Linfoma/virologia , Reação em Cadeia da Polimerase , RNA Viral/isolamento & purificação , Estudos Soroepidemiológicos
6.
PLoS One ; 9(11): e112642, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25384040

RESUMO

A unique feature of both human herpesvirus 6A and B (HHV-6A and B) among human herpesviruses is their ability to integrate into chromosomal telomeres. In some individuals integrated viral genomes are present in the germ-line and result in the vertical transmission of HHV-6; however, little is known about the disease associations of germ-line transmitted, chromosomally integrated HHV-6 (ciHHV-6). Recent publications suggest that HHV-6 is associated with classical Hodgkin lymphoma (cHL). Here we examine the prevalence of ciHHV-6 in 936 cases of cHL and 563 controls by screening with a duplex TaqMan assay and confirming with droplet digital PCR. ciHHV-6 was detected in 10/563 (1.8%) controls and in all but one individual the virus was HHV-6B. Amongst cases 16/936 (1.7%) harboured ciHHV-6, thus demonstrating no association between ciHHV-6 and risk of cHL.


Assuntos
Cromossomos Humanos/genética , Células Germinativas/virologia , Herpesvirus Humano 6/genética , Doença de Hodgkin/virologia , Infecções por Roseolovirus/genética , Integração Viral , Estudos de Casos e Controles , Cromossomos Humanos/virologia , DNA Viral/genética , Feminino , Herpesvirus Humano 6/fisiologia , Doença de Hodgkin/genética , Humanos , Masculino , Reação em Cadeia da Polimerase/métodos , Telômero
7.
Planta ; 239(3): 605-13, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24281299

RESUMO

Physcomitrella patens is a model bryophyte representing an early land plant in the green plant lineage. This organism possesses many advantages as a model organism. Its genome has been sequenced, its predominant life cycle stage is the haploid gametophyte, it is readily transformable and it can integrate transformed DNA into its genome by homologous recombination. One limitation for the use of P. patens in photosynthesis research is its reported inability to grow photoheterotrophically, in the presence of sucrose and the Photosystem II inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea, which prevents linear photosynthetic electron transport. In this communication we describe the facile isolation of a P. patens strain which can grow photoheterotrophically. Additionally, we have examined a number of photosynthetic parameters for this strain grown under photoautotrophic, mixotrophic (in the presence of sucrose) and photoheterotrophic conditions, as well as the 3-(3,4-dichlorophenyl)-1,1-dimethylurea-inhibited state. The ability to grow P. patens photoheterotrophically should significantly facilitate its use in photosynthetic studies.


Assuntos
Bryopsida/crescimento & desenvolvimento , Bryopsida/metabolismo , Processos Heterotróficos , Diurona , Fotossíntese , Sacarose/metabolismo
8.
Zootaxa ; 3640: 57-69, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26000404

RESUMO

Two new monotypic spittlebug genera and their type species in the family Machaerotidae, subfamily Enderleiniinae, are described and illustrated: Labramachaerota korupa gen. & sp. n. (with type locality in Cameroon) and Kyphomachaerota maaia gen. & sp. n. (with type locality in Sarawak, Malaysia).


Assuntos
Hemípteros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Feminino , Hemípteros/anatomia & histologia , Hemípteros/crescimento & desenvolvimento , Malásia , Masculino , Tamanho do Órgão
9.
J Virol ; 87(2): 978-90, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23135716

RESUMO

Herpes simplex virus 1 (HSV-1) immediate-early protein ICP0 is required for efficient lytic infection and productive reactivation from latency and induces derepression of quiescent viral genomes. Despite being unrelated at the sequence level, ICP0 and human cytomegalovirus proteins IE1 and pp71 share some functional similarities in their abilities to counteract antiviral restriction mediated by components of cellular nuclear structures known as ND10. To investigate the extent to which IE1 and pp71 might substitute for ICP0, cell lines were developed that express either IE1 or pp71, or both together, in an inducible manner. We found that pp71 dissociated the hDaxx-ATRX complex and inhibited accumulation of these proteins at sites juxtaposed to HSV-1 genomes but had no effect on the promyelocytic leukemia protein (PML) or Sp100. IE1 caused loss of the small ubiquitin-like modifier (SUMO)-conjugated forms of PML and Sp100 and inhibited the recruitment of these proteins to HSV-1 genome foci but had little effect on hDaxx or ATRX in these assays. Both IE1 and pp71 stimulated ICP0-null mutant plaque formation, but neither to the extent achieved by ICP0. The combination of IE1 and pp71, however, inhibited recruitment of all ND10 proteins to viral genome foci, stimulated ICP0-null mutant HSV-1 plaque formation to near wild-type levels, and efficiently induced derepression of quiescent HSV-1 genomes. These results suggest that ND10-related intrinsic resistance results from the additive effects of several ND10 components and that the effects of IE1 and pp71 on subsets of these components combine to mirror the overall activities of ICP0.


Assuntos
Citomegalovirus/genética , Teste de Complementação Genética , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/deficiência , Proteínas Imediatamente Precoces/metabolismo , Ubiquitina-Proteína Ligases/deficiência , Proteínas Virais/metabolismo , Replicação Viral , Animais , Linhagem Celular , Herpesvirus Humano 1/genética , Humanos , Proteínas Imediatamente Precoces/genética , Ensaio de Placa Viral , Proteínas Virais/genética
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