The infection of Bombyx mori nucleopolyhedrovirus (BmNPV) is one of the main causes of economic losses in sericulture. Thus, it is essential to establish rapid and effective method for BmNPV detection. In the present study, we have developed a recombinase-aided amplification (RAA) to amplify the BmNPV genomic DNA at 37 °C within 30 min, and achieved a rapid detection method by coupling with a lateral flow dipstick (LFD). The RAA-LFD method had a satisfactory detection limit of 6 copies/μL of recombinant plasmid pMD19-T-IE1, and BmNPV infection of silkworm can be detected 12 h post-infection. This method was highly specific for BmNPV, and without cross-reactivity to other silkworm pathogens. In contrast to conventional polymerase chain reaction (PCR), the RAA-LFD assay showed higher sensitivity, cost-saving, and especially is apt to on-site detection of BmNPV infection in the sericulture production.
- MeSH
- bourec * virologie MeSH
- DNA virů genetika MeSH
- limita detekce MeSH
- nukleopolyhedroviry * genetika izolace a purifikace MeSH
- rekombinasy * metabolismus genetika MeSH
- senzitivita a specificita MeSH
- techniky amplifikace nukleových kyselin * metody MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
OBJECTIVE: Members of the insulin/insulin-like growth factor (IGF) superfamily are well conserved across the evolutionary tree. We recently showed that four viruses in the Iridoviridae family possess genes that encode proteins highly homologous to human insulin/IGF-1. Using chemically synthesized single-chain (sc), i.e., IGF-1-like, forms of the viral insulin/IGF-1-like peptides (VILPs), we previously showed that they can stimulate human receptors. Because these peptides possess potential cleavage sites to form double chain (dc), i.e., more insulin-like, VILPs, in this study, we have characterized dc forms of VILPs for Grouper iridovirus (GIV), Singapore grouper iridovirus (SGIV) and Lymphocystis disease virus-1 (LCDV-1) for the first time. METHODS: The dcVILPs were chemically synthesized. Using murine fibroblast cell lines overexpressing insulin receptor (IR-A or IR-B) or IGF1R, we first determined the binding affinity of dcVILPs to the receptors and characterized post-receptor signaling. Further, we used C57BL/6J mice to study the effect of dcVILPs on lowering blood glucose. We designed a 3-h dcVILP in vivo infusion experiment to determine the glucose uptake in different tissues. RESULTS: GIV and SGIV dcVILPs bind to both isoforms of human insulin receptor (IR-A and IR-B) and to the IGF1R, and for the latter, show higher affinity than human insulin. These dcVILPs stimulate IR and IGF1R phosphorylation and post-receptor signaling in vitro and in vivo. Both GIV and SGIV dcVILPs stimulate glucose uptake in mice. In vivo infusion experiments revealed that while insulin (0.015 nmol/kg/min) and GIV dcVILP (0.75 nmol/kg/min) stimulated a comparable glucose uptake in heart and skeletal muscle and brown adipose tissue, GIV dcVILP stimulated 2-fold higher glucose uptake in white adipose tissue (WAT) compared to insulin. This was associated with increased Akt phosphorylation and glucose transporter type 4 (GLUT4) gene expression compared to insulin in WAT. CONCLUSIONS: Our results show that GIV and SGIV dcVILPs are active members of the insulin superfamily with unique characteristics. Elucidating the mechanism of tissue specificity for GIV dcVILP will help us to better understand insulin action, design new analogs that specifically target the tissues and provide new insights into their potential role in disease.
- MeSH
- bílá tuková tkáň metabolismus MeSH
- buněčné linie MeSH
- CD antigeny MeSH
- fosforylace MeSH
- glukosa metabolismus MeSH
- hnědá tuková tkáň metabolismus MeSH
- insulinu podobný růstový faktor I metabolismus MeSH
- inzulin genetika metabolismus MeSH
- inzuliny metabolismus MeSH
- Iridovirus genetika MeSH
- iridoviry genetika MeSH
- lidé MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- receptor IGF typ 1 genetika metabolismus MeSH
- receptor inzulinu metabolismus MeSH
- signální transdukce MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Although the modulation of host physiology has been interpreted as an essential process supporting baculovirus propagation, the requirement of energy supply for host antivirus reactions could not be ruled out. Our present study showed that metabolic induction upon AcMNPV (budded virus) infection of Bombyx mori stimulated virus clearance and production of the antivirus protein, gloverin. In addition, we demonstrated that adenosine receptor signaling (AdoR) played an important role in regulating such metabolic reprogramming upon baculovirus infection. By using a second lepidopteran model, Spodoptera frugiperda Sf-21 cells, we demonstrated that the glycolytic induction regulated by adenosine signaling was a conservative mechanism modulating the permissiveness of baculovirus infection. Another interesting finding in our present study is that both BmNPV and AcMNPV infection cause metabolic activation, but it appears that BmNPV infection moderates the level of ATP production, which is in contrast to a dramatic increase upon AcMNPV infection. We identified potential AdoR miRNAs induced by BmNPV infection and concluded that BmNPV may attempt to minimize metabolic activation by suppressing adenosine signaling and further decreasing the host's anti-baculovirus response. Our present study shows that activation of energy synthesis by adenosine signaling upon baculovirus infection is a host physiological response that is essential for supporting the innate immune response against infection.
- MeSH
- adenosin metabolismus MeSH
- adenosintrifosfát biosyntéza MeSH
- bourec metabolismus virologie MeSH
- deoxyglukosa farmakologie MeSH
- energetický metabolismus MeSH
- glykolýza účinky léků genetika MeSH
- hmyzí proteiny metabolismus MeSH
- infekce DNA virem metabolismus virologie MeSH
- interakce hostitele a patogenu imunologie MeSH
- mezibuněčné signální peptidy a proteiny metabolismus MeSH
- nukleopolyhedroviry fyziologie MeSH
- purinergní receptory P1 genetika metabolismus MeSH
- replikace viru účinky léků MeSH
- Sf9 buňky MeSH
- Spodoptera MeSH
- transfekce MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Among the many diseases compromising the well-being of the honey bee (Apis mellifera) the chronic paralysis syndrome of adult honey bees is one of the best described. The causative agent, chronic bee paralysis virus (CBPV), is a positive sense, single-stranded RNA virus with a segmented genome. Segment 1 encodes three putative open reading frames (ORFs), including the RNA-dependent RNA polymerase and other non-structural protein coding regions. Segment 2 encodes four putative ORFs, which contain the genes of supposed structural proteins. In this study, we established a reverse genetic system for CBPV by molecular cloning of DNA copies of both genome segments. CBPV rescue was studied in imago and honey bee pupae infection models. Virus replication and progeny virus production was only initiated when capped RNAs of both genome segments were injected in honey bees. As injection of these clonal RNAs caused clinical symptoms similar to wild-type CBPV infection, we conclude that the novel molecular clone fulfilled Koch's postulates. Our virus clone will enable in-depth analysis of CBPV pathogenesis and help to increase knowledge about this important honey bee disease.
Heliothis zea nudivirus-1 (HzNV-1) is an insect virus that can induce both lytic and latent infections in various insect cell lines. During latent infection, several microRNAs (miRNAs) are produced from persistency-associated gene 1 (pag1) as the only detectable HzNV-1 transcript. Previous studies have shown that the pag1 gene suppresses the immediate-early gene hhi1 and promotes host switching into a latent infection via miRNAs derived from pag1. Although other functions of the miRNAs derived from pag1 have not yet been elucidated, several studies have suggested that miRNAs encoded from latency-associated genes can regulate histone-associated enzymes. Because pag1 is a noncoding transcript, it potentially regulates host chromatin structure through miRNAs upon infection. Nevertheless, the exact mechanism by which pag1 alters viral infections remains unknown. In this study, we found that the pag1-encoded miRNA miR-420 suppresses expression of the histone modification-associated enzyme su(var)3-9. Therefore, this miRNA causes histone modification to promote HzNV-1 infection. These results suggest that HzNV-1 may directly influence epigenetic regulation in host cells through interactions with pag1 miRNAs to promote lytic infection. This study provides us with a better understanding of both the HzNV-1 infection pathway and the relationship between viral miRNAs and epigenetic regulation.
- MeSH
- epigeneze genetická * MeSH
- histony metabolismus MeSH
- hmyzí proteiny metabolismus MeSH
- metylace MeSH
- mikro RNA biosyntéza MeSH
- nukleopolyhedroviry fyziologie MeSH
- regulace exprese virových genů * MeSH
- RNA virová biosyntéza MeSH
- Sf9 buňky MeSH
- Spodoptera * metabolismus virologie MeSH
- virové proteiny metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- Varroidae patogenita MeSH
- včely * virologie MeSH
- virové nemoci * diagnóza epidemiologie etiologie veterinární MeSH
- viry hmyzu klasifikace MeSH
- zdravotní stav populace MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- přehledy MeSH
Cíl práce: Autochtonní přenos nemocí, kde komáři figurují v roli vektorů, není v České republice častým jevem, a komáři jsou zde proto považováni především za obtížný hmyz, jenž při kalamitách významně snižuje kvalitu života v postižených oblastech. Osobní ochrana by proto neměla být podceňována. V současné době jsou zde stále s oblibou využívány repelenty domácí výroby. Cílem tohoto článku bylo přinést nové poznatky o jejich účinku a chemické složení, včetně detekce potenciálních alergenů, těchto repelentů. Metodika: Na základě on-line dostupných receptur byly vybrány a následně připraveny čtyři varianty domácích repelentů, s obsahem listů z rozmarýnu (Rosmarinus officinalis), pelyňku (Artemisia absinthium), ořešáku (Juglans regia) a celých hřebíčků (Syzygium aromaticum). Byliny použité k přípravě testovaných repelentů byly získány z běžně dostupných komerčních zdrojů bez bližší specifikace. Účinnost takto připravených repelentů byla otestována na komárech Aedes aegypti na 10 dobrovolnících pro každý přípravek. Dále byla provedena plynová chromatografie za účelem detekce potenciální přítomnosti alergenů. Výsledky: Po 10 minutách od aplikace repelentu vykázal vyšší repelentní účinek pouze hřebíčkový extrakt (73,1 %) a výluh ořešákových listů (49 %), oba v kombinaci s přípravkem ALPATM. V průběhu testování se účinnost postupně snižovala na 46,5 %, respektive 34,3 % po 30 minutách a 30,3 %, respektive 18,2 % po 60 minutách, kdy byl test ukončen. Výluhy z rozmarýnu a pelyňku neměly žádný repelentní efekt. Screeningovým měřením byly v testovaných vzorcích detekovány některé potenciální alergeny včetně cinnamaldehydu, eugenolu či kumarinu. Závěr: Repelence testovaných přípravků byla během 60minutového testu nevýznamná nebo nepříliš stabilní. Repelenty vyrobené z hřebíčku a ořešáku v kombinaci s alkoholovým přípravkem mohou být považovány za alternativu ke snížení obtížnosti bodavého hmyzu, nicméně je nelze považovat za ochranu spolehlivou a vhodnou pro oblasti s častým výskytem komáry přenosných onemocnění. Vzhledem k prokázané přítomnosti potenciálních alergenů je třeba zvážit nejen rizika využití repelentů domácí výroby z hlediska přenosu patogenů, ale i možných alergických reakcí u citlivějších jedinců.
Objectives: In the Czech Republic, autochtonous transmission of mosquito borne diseases is not common; however, the need for personal protection should not be underestimated. Many people still rely on homemade repellents utilizing recipes based on local folk wisdom that are published annually in local Czech media. Despite minimal disease risk, nuisance biting and potential allergic responses make it essential to evaluate the chemical composition, effect, and duration of four homemade repellents often used and determine the necessity for public health education on application and use of alternative repellent products. Methods: A review of local web-based media was conducted to identify the most commonly advertised homemade repellent products. The top four products were rosemary (Rosmarinus officinalis), sagebrush (Artemisia absinthium), walnut-tree (Juglans regia) leaves and clove (Syzygium aromaticum). These repellents were then prepared following the published recipes to evaluate their repellency effects, and reveal potential allergen presence. A bioassay against Aedes aegypti was conducted on ten volunteers for each repellent and the chemical composition was detected using gas chromatography. Results: Significant initial repellency effect was found in mixtures of the clove (73.1%) and walnut leaves (49.0%) with ALPATM herbal embrocation after 10 minutes. The efficacy decreased to 46.5% and 34.3 % after 30 minutes, respectively; and, 30.3 and 18.2%, 60 minutes after the application. The remaining two samples, Rosmarinus officinalis and Artemisia absinthium solutions, exhibited no significant effects against Ae. aegypti. The evidence of allergens including cinnamic aldehyde, eugenol and coumarin were detected indicating potential concerns for product safety. Conclusion: The homemade repellents reviewed were either ineffective or had unstable repellency effect within one hour. The low efficacy of these products may be appropriate to decrease nuisance biting, but should not be considered for primary prevention against mosquito borne diseases in areas with active disease transmission. Additionally, more research is needed to assess rates of allergic responses to homemade repellent products.
- Klíčová slova
- přírodní repelent,
- MeSH
- Aedes účinky léků MeSH
- alergeny MeSH
- Densovirinae MeSH
- Juglans MeSH
- lidé MeSH
- pelyněk MeSH
- plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
- repelenty proti hmyzu * MeSH
- rostlinné extrakty * MeSH
- rozmarýn MeSH
- Syzygium MeSH
- Check Tag
- lidé MeSH
- Geografické názvy
- Česká republika MeSH
Commercial Cydia pomonella granulovirus (CpGV) products have been successfully applied to control codling moth (CM) in organic and integrated fruit production for more than 30 years. Since 2005, resistance against the widely used isolate CpGV-M has been reported from different countries in Europe. The inheritance of this so-called type I resistance is dominant and linked to the Z chromosome. Recently, a second form (type II) of CpGV resistance in CM was reported from a field population (NRW-WE) in Germany. Type II resistance confers reduced susceptibility not only to CpGV-M but to most known CpGV isolates and it does not follow the previously described Z-linked inheritance of type I resistance. To further analyze type II resistance, two CM strains, termed CpR5M and CpR5S, were generated from parental NRW-WE by repeated mass crosses and selection using the two isolates CpGV-M and CpGV-S, respectively. Both CpR5M and CpR5S were considered to be genetically homogeneous for the presence of the resistance allele(s). By crossing and backcrossing experiments with a susceptible CM strain, followed by resistance testing of the offspring, an autosomal dominant inheritance of resistance was elucidated. In addition, cross-resistance to CpGV-M and CpGV-S was detected in both strains, CpR5M and CpR5S. To test the hypothesis that the autosomal inheritance of type II resistance was caused by a large interchromosomal rearrangement involving the Z chromosome, making type I resistance appear to be autosomal in these strains; fluorescence in situ hybridization with bacterial artificial chromosome probes (BAC-FISH) was used to physically map the Z chromosomes of different CM strains. Conserved synteny of the Z-linked genes in CpR5M and other CM strains rejects this hypothesis and argues for a novel genetic and functional mode of resistance in CM populations with type II resistance.
- MeSH
- Betabaculovirus genetika fyziologie MeSH
- chromozomy hmyzu genetika MeSH
- genom virový genetika MeSH
- hybridizace genetická MeSH
- můry genetika fyziologie virologie MeSH
- typy dědičnosti * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The worldwide population of western honey bees (Apis mellifera) is under pressure from habitat loss, environmental stress, and pathogens, particularly viruses that cause lethal epidemics. Deformed wing virus (DWV) from the family Iflaviridae, together with its vector, the mite Varroa destructor, is likely the major threat to the world's honey bees. However, lack of knowledge of the atomic structures of iflaviruses has hindered the development of effective treatments against them. Here, we present the virion structures of DWV determined to a resolution of 3.1 Å using cryo-electron microscopy and 3.8 Å by X-ray crystallography. The C-terminal extension of capsid protein VP3 folds into a globular protruding (P) domain, exposed on the virion surface. The P domain contains an Asp-His-Ser catalytic triad that is, together with five residues that are spatially close, conserved among iflaviruses. These residues may participate in receptor binding or provide the protease, lipase, or esterase activity required for entry of the virus into a host cell. Furthermore, nucleotides of the DWV RNA genome interact with VP3 subunits. The capsid protein residues involved in the RNA binding are conserved among honey bee iflaviruses, suggesting a putative role of the genome in stabilizing the virion or facilitating capsid assembly. Identifying the RNA-binding and putative catalytic sites within the DWV virion structure enables future analyses of how DWV and other iflaviruses infect insect cells and also opens up possibilities for the development of antiviral treatments.
- MeSH
- elektronová kryomikroskopie MeSH
- kapsida ultrastruktura MeSH
- konformace proteinů MeSH
- molekulární modely MeSH
- počítačové zpracování obrazu MeSH
- proteinové domény MeSH
- RNA-viry ultrastruktura MeSH
- sekvence aminokyselin MeSH
- včely virologie MeSH
- virion ultrastruktura MeSH
- virové plášťové proteiny chemie ultrastruktura MeSH
- viry hmyzu ultrastruktura MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Viral diseases are a major threat to honeybee (Apis mellifera) populations worldwide and therefore an important factor in reliable crop pollination and food security. Black queen cell virus (BQCV) is the etiological agent of a fatal disease of honeybee queen larvae and pupae. The virus belongs to the genus Triatovirus from the family Dicistroviridae, which is part of the order Picornavirales Here we present a crystal structure of BQCV determined to a resolution of 3.4 Å. The virion is formed by 60 copies of each of the major capsid proteins VP1, VP2, and VP3; however, there is no density corresponding to a 75-residue-long minor capsid protein VP4 encoded by the BQCV genome. We show that the VP4 subunits are present in the crystallized virions that are infectious. This aspect of the BQCV virion is similar to that of the previously characterized triatoma virus and supports the recent establishment of the separate genus Triatovirus within the family Dicistroviridae The C terminus of VP1 and CD loops of capsid proteins VP1 and VP3 of BQCV form 34-Å-tall finger-like protrusions at the virion surface. The protrusions are larger than those of related dicistroviruses.IMPORTANCE The western honeybee is the most important pollinator of all, and it is required to sustain the agricultural production and biodiversity of wild flowering plants. However, honeybee populations worldwide are suffering from virus infections that cause colony losses. One of the most common, and least known, honeybee pathogens is black queen cell virus (BQCV), which at high titers causes queen larvae and pupae to turn black and die. Here we present the three-dimensional virion structure of BQCV, determined by X-ray crystallography. The structure of BQCV reveals large protrusions on the virion surface. Capsid protein VP1 of BQCV does not contain a hydrophobic pocket. Therefore, the BQCV virion structure provides evidence that capsid-binding antiviral compounds that can prevent the replication of vertebrate picornaviruses may be ineffective against honeybee virus infections.
- MeSH
- Dicistroviridae ultrastruktura MeSH
- konformace proteinů MeSH
- krystalografie rentgenová MeSH
- molekulární modely MeSH
- včely virologie MeSH
- virion ultrastruktura MeSH
- virové plášťové proteiny chemie MeSH
- virové struktury MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH