| evidence for ribosomal frameshifting and a novel overlapping gene in the genomes of insect-specific flaviviruses. | flaviviruses have a positive-sense, single-stranded rna genome of approximately 11 kb, encoding a large polyprotein that is cleaved to produce approximately 10 mature proteins. cell fusing agent virus, kamiti river virus, culex flavivirus and several recently discovered flaviviruses have no known vertebrate host and apparently infect only insects. we present compelling bioinformatic evidence for a 253-295 codon overlapping gene (designated fifo) conserved throughout these insect-specific flavivi ... | 2010 | 20097399 |
| mosquito cell lines: history, isolation, availability and application to assess the threat of arboviral transmission in the united kingdom. | mosquitoes are highly effective vectors for transmission of human and animal pathogens. understanding the relationship between pathogen and vector is vital in developing strategies to predict and prevent transmission. cell lines derived from appropriate mosquito hosts provide a relatively simple tool for investigating the interaction between the host and viruses transmitted by mosquitoes. this review provides a brief overview of the development of mosquito cell lines, methods of isolation, their ... | 2014 | 25141888 |
| the insect-specific palm creek virus modulates west nile virus infection in and transmission by australian mosquitoes. | insect-specific viruses do not replicate in vertebrate cells, but persist in mosquito populations and are highly prevalent in nature. these viruses may naturally regulate the transmission of pathogenic vertebrate-infecting arboviruses in co-infected mosquitoes. following the isolation of the first australian insect-specific flavivirus (isf), palm creek virus (pcv), we investigated routes of infection and transmission of this virus in key australian arbovirus vectors and its impact on replication ... | 2016 | 27457250 |
| a new insect-specific flavivirus from northern australia suppresses replication of west nile virus and murray valley encephalitis virus in co-infected mosquito cells. | recent reports of a novel group of flaviviruses that replicate only in mosquitoes and appear to spread through insect populations via vertical transmission have emerged from around the globe. to date, there is no information on the presence or prevalence of these insect-specific flaviviruses (isfs) in australian mosquito species. to assess whether such viruses occur locally, we used reverse transcription-polymerase chain reaction (rt-pcr) and flavivirus universal primers that are specific to the ... | 2013 | 23460804 |
| transmission dynamics of an insect-specific flavivirus in a naturally infected culex pipiens laboratory colony and effects of co-infection on vector competence for west nile virus. | we established a laboratory colony of culex pipiens mosquitoes from eggs collected in colorado and discovered that mosquitoes in the colony are naturally infected with culex flavivirus (cxfv), an insect-specific flavivirus. in this study we examined transmission dynamics of cxfv and effects of persistent cxfv infection on vector competence for west nile virus (wnv). we found that vertical transmission is the primary mechanism for persistence of cxfv in cx. pipiens, with venereal transmission pot ... | 2012 | 22425062 |
| viral interference and persistence in mosquito-borne flaviviruses. | mosquito-borne flaviviruses are important pathogens for humans, and the detection of two or more flaviviruses cocirculating in the same geographic area has often been reported. however, the epidemiological impact remains to be determined. mosquito-borne flaviviruses are primarily transmitted through aedes and culex mosquitoes; these viruses establish a life-long or persistent infection without apparent pathological effects. this establishment requires a balance between virus replication and the ... | 2015 | 26583158 |
| novel virus discovery and genome reconstruction from field rna samples reveals highly divergent viruses in dipteran hosts. | we investigated whether small rna (srna) sequenced from field-collected mosquitoes and chironomids (diptera) can be used as a proxy signature of viral prevalence within a range of species and viral groups, using srnas sequenced from wild-caught specimens, to inform total rna deep sequencing of samples of particular interest. using this strategy, we sequenced from adult anopheles maculipennis s.l. mosquitoes the apparently nearly complete genome of one previously undescribed virus related to chro ... | 2013 | 24260463 |
| ecuador paraiso escondido virus, a new flavivirus isolated from new world sand flies in ecuador, is the first representative of a novel clade in the genus flavivirus. | a new flavivirus, ecuador paraiso escondido virus (epev), named after the village where it was discovered, was isolated from sand flies (psathyromyia abonnenci, formerly lutzomyia abonnenci) that are unique to the new world. this represents the first sand fly-borne flavivirus identified in the new world. epev exhibited a typical flavivirus genome organization. nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. phylogenetic analysis o ... | 2015 | 26355096 |
| new insights into flavivirus evolution, taxonomy and biogeographic history, extended by analysis of canonical and alternative coding sequences. | to generate the most diverse phylogenetic dataset for the flaviviruses to date, we determined the genomic sequences and phylogenetic relationships of 14 flaviviruses, of which 10 are primarily associated with culex spp. mosquitoes. we analyze these data, in conjunction with a comprehensive collection of flavivirus genomes, to characterize flavivirus evolutionary and biogeographic history in unprecedented detail and breadth. based on the presumed introduction of yellow fever virus into the americ ... | 2015 | 25719412 |
| insect-specific flaviviruses: a systematic review of their discovery, host range, mode of transmission, superinfection exclusion potential and genomic organization. | there has been a dramatic increase in the number of insect-specific flaviviruses (isfs) discovered in the last decade. historically, these viruses have generated limited interest due to their inability to infect vertebrate cells. this viewpoint has changed in recent years because some isfs have been shown to enhance or suppress the replication of medically important flaviviruses in co-infected mosquito cells. additionally, comparative studies between isfs and medically important flaviviruses can ... | 2015 | 25866904 |
| insect-specific virus discovery: significance for the arbovirus community. | arthropod-borne viruses (arboviruses), especially those transmitted by mosquitoes, are a significant cause of morbidity and mortality in humans and animals worldwide. recent discoveries indicate that mosquitoes are naturally infected with a wide range of other viruses, many within taxa occupied by arboviruses that are considered insect-specific. over the past ten years there has been a dramatic increase in the literature describing novel insect-specific virus detection in mosquitoes, which has p ... | 2015 | 26378568 |
| novel flaviviruses detected in different species of mosquitoes in spain. | abstract we report the characterization of three novel flaviviruses isolated in spain. marisma mosquito virus, a novel mosquito borne virus, was isolated from ochlerotatus caspius mosquitoes; spanish ochlerotatus flavivirus and spanish culex flavivirus, two novel insect flaviviruses, were isolated from oc. caspius and culex pipiens, respectively. during this investigation, we designed a sensitive rt-nested polymerase chain reaction method that amplifies a 1019bp fragment of the flavivirus ns5 ... | 2011 | 22022811 |
| insect-specific flaviviruses from culex mosquitoes in colorado, with evidence of vertical transmission. | mosquitoes were collected in colorado during 2006 and 2007 to examine spatial and seasonal patterns of risk for exposure to culex vectors and west nile virus. we used universal flavivirus primers to test pools of culex mosquitoes for viral rna. this led to the detection and subsequent isolation of two insect-specific flaviviruses: culex flavivirus (cxfv), which was first described from japan, and a novel insect flavivirus, designated calbertado virus (clbov), which has also been detected in cali ... | 2011 | 21734144 |
| distribution and phylogenetic comparisons of a novel mosquito flavivirus sequence present in culex tarsalis mosquitoes from western canada with viruses isolated in california and colorado. | in a previous study, a new flavivirus genome sequence was identified in culex tarsalis mosquitoes obtained in alberta, canada and was shown to be genetically related to but distinct from members of the insect-specific flaviviruses. nonstructural protein 5-encoding sequences amplified from cx. tarsalis pools from western canada have shown a high similarity to genome sequences of novel flaviviruses isolated from mosquitoes in california and colorado. despite wide distribution of this virus, design ... | 2011 | 21734143 |
| structural and functional analyses of a conserved hydrophobic pocket of flavivirus methyltransferase. | the flavivirus methyltransferase (mtase) sequentially methylates the n7 and 2'-o positions of the viral rna cap (gpppa-rna → m(7)gpppa-rna → m(7)gpppam-rna), using s-adenosyl-l-methionine (adomet) as a methyl donor. we report here that sinefungin (sin), an adomet analog, inhibits several flaviviruses through suppression of viral mtase. the crystal structure of west nile virus mtase in complex with sin inhibitor at 2.0-å resolution revealed a flavivirus-conserved hydrophobic pocket located next t ... | 2010 | 20685660 |
| isolation and sequence analysis of culex flavivirus from culex interrogator and culex quinquefasciatus in the yucatan peninsula of mexico. | previously, we reported a high prevalence of culex flavivirus (cxfv) in culex quinquefasciatus (say) in the yucatan peninsula of mexico. to determine whether other culex spp. mosquitoes in this region are susceptible to natural cxfv infection, cx. bahamensis (dyar and knab), cx. coronator (dyar and knab), cx. interrogator (dyar and knab), cx. nigripalpus (theobald) and cx. opisthopus (komp) in the yucatan peninsula of mexico were tested for cxfv. two pools of cx. interrogator were positive. the ... | 2010 | 20379749 |
| detection of flaviviruses and orthobunyaviruses in mosquitoes in the yucatan peninsula of mexico in 2008. | a total of 191,244 mosquitoes from 24 species were collected in the yucatan peninsula of mexico from january to december 2008, and tested for the presence of cytopathic virus by virus isolation in vero cells. eighteen virus isolates were obtained, all of which were orthobunyaviruses. these were identified by reverse transcription-polymerase chain reaction (rt-pcr) and nucleotide sequencing as cache valley virus (n=17) and south river virus (n=1). a subset (n=20,124) of culex quinquefasciatus col ... | 2010 | 20370430 |
| isolation of a novel species of flavivirus and a new strain of culex flavivirus (flaviviridae) from a natural mosquito population in uganda. | the genus flavivirus, which contains approximately 70 single-stranded, positive-sense rna viruses, represents a unique model for studying the evolution of vector-borne disease, as it includes viruses that are mosquito-borne, tick-borne or have no known vector. both theoretical work and field studies suggest the existence of a large number of undiscovered flaviviruses. recently, the first isolation of cell fusing agent virus (cfav) was reported from a natural mosquito population in puerto rico, a ... | 2009 | 19656970 |
| detection of mosquito-only flaviviruses in europe. | the genus flavivirus, family flaviviridae, includes a number of important arthropod-transmitted human pathogens such as dengue viruses, west nile virus, japanese encephalitis virus and yellow fever virus. in addition, the genus includes flaviviruses without a known vertebrate reservoir, which have been detected only in insects, particularly in mosquitoes, such as cell fusing agent virus, kamiti river virus, culex flavivirus, aedes flavivirus, quang binh virus, nakiwogo virus and calbertado virus ... | 2012 | 22377581 |
| detection of quang binh virus from mosquitoes in china. | flaviviruses present a wide range of genetic diversity and exhibit diverse host relationships. mosquito-borne flaviviruses have recently been isolated and characterized worldwide. yunnan province of china is one of the richest areas of species diversity and is the center of multi-species evolution in mainland asia, which supports the circulation of numerous arthropod-borne viruses (arboviruses). in a screening program of arboviruses, mosquitoes were collected during the mosquito activity season ... | 2014 | 24342141 |
| characterization of a novel negevirus and a novel bunyavirus isolated from culex (culex) declarator mosquitoes in trinidad. | pools of mosquitoes were tested for insect-specific viruses using cytopathic effect (cpe) assays on aedes albopictus (c6/36) cells. illumina sequencing of rna from pool tr7094, which produced extensive cpe 2 days post-infection, yielded the complete genome sequences of a previously unknown bunyavirus, designated cumuto virus (cumv), and a second virus designated wallerfield virus (walv). walv shared highest amino acid identity (60.1 %) with dezidougou virus from côte d'ivoire, a positive-sense, ... | 2013 | 24262627 |
| genetic characterization of an insect-specific flavivirus isolated from culex theileri mosquitoes collected in southern portugal. | we describe the full genetic characterization of an insect-specific flavivirus (isf) from culex theileri (theobald) mosquitoes collected in portugal. this represents the first isolation and full characterization of an isf from portuguese mosquitoes. the virus, designated ctfv, for culex theileri flavivirus, was isolated in the c6/36 stegomyia albopicta (=aedes albopictus) cell line, and failed to replicate in vertebrate (vero) cells in common with other isfs. the ctfv genome encodes a single pol ... | 2012 | 22579596 |
| discovery of novel viruses in mosquitoes from the zambezi valley of mozambique. | mosquitoes carry a wide variety of viruses that can cause vector-borne infectious diseases and affect both human and veterinary public health. although mozambique can be considered a hot spot for emerging infectious diseases due to factors such as a rich vector population and a close vector/human/wildlife interface, the viral flora in mosquitoes have not previously been investigated. in this study, viral metagenomics was employed to analyze the viral communities in culex and mansonia mosquitoes ... | 2016 | 27682810 |
| novel insect-specific flavivirus isolated from northern europe. | mosquitoes collected in finland were screened for flaviviral rna leading to the discovery and isolation of a novel flavivirus designated hanko virus (hankv). virus characterization, including phylogenetic analysis of the complete coding sequence, confirmed hankv as a member of the "insect-specific" flavivirus (isf) group. hankv is the first member of this group isolated from northern europe, and therefore the first northern european isf for which the complete coding sequence has been determined. ... | 2012 | 22999256 |
| characterization of a novel insect-specific flavivirus from brazil: potential for inhibition of infection of arthropod cells with medically important flaviviruses. | in the past decade, there has been an upsurge in the number of newly described insect-specific flaviviruses isolated pan-globally. we recently described the isolation of a novel flavivirus (tentatively designated 'nhumirim virus'; nhuv) that represents an example of a unique subset of apparently insect-specific viruses that phylogenetically affiliate with dual-host mosquito-borne flaviviruses despite appearing to be limited to replication in mosquito cells. we characterized the in vitro growth p ... | 2014 | 25146007 |
| mercadeo virus: a novel mosquito-specific flavivirus from panama. | viruses in the genus flavivirus (family flaviviridae) include many arthropod-borne viruses of public health and veterinary importance. however, during the past two decades an explosion of novel insect-specific flaviviruses (isfs), some closely related to vertebrate pathogens, have been discovered. although many flavivirus pathogens of vertebrates have been isolated from naturally infected mosquitoes in panama, isfs have not previously been reported from the country. this report describes the iso ... | 2015 | 26304915 |
| endogenous viral elements in animal genomes. | integration into the nuclear genome of germ line cells can lead to vertical inheritance of retroviral genes as host alleles. for other viruses, germ line integration has only rarely been documented. nonetheless, we identified endogenous viral elements (eves) derived from ten non-retroviral families by systematic in silico screening of animal genomes, including the first endogenous representatives of double-stranded rna, reverse-transcribing dna, and segmented rna viruses, and the first endogenou ... | 2010 | 21124940 |
| Molecular evolution of the insect-specific flaviviruses. | There has been an explosion in the discovery of 'insect-specific' flaviviruses and/or their related sequences in natural mosquito populations. Herein we review all 'insect-specific' flaviviral sequences currently available and conduct phylogenetic analyses of both the 'insect-specific' flaviviruses and available sequences of the entire genus Flavivirus. We show that there is no statistical support for virus-mosquito co-divergence, suggesting that the 'insect-specific' flaviviruses may have under ... | 2011 | 22012464 |