One of the major functions of programmed cell death (apoptosis) is the removal of cells that suffered oncogenic mutations, thereby preventing cancerous transformation. By making use of a Double-Headed-EP (DEP) transposon, a P element derivative made in our laboratory, we made an insertional mutagenesis screen in Drosophila melanogaster to identify genes that, when overexpressed, suppress the p53-activated apoptosis. The DEP element has Gal4-activatable, outward-directed UAS promoters at both ends, which can be deleted separately in vivo. In the DEP insertion mutants, we used the GMR-Gal4 driver to induce transcription from both UAS promoters and tested the suppression effect on the apoptotic rough eye phenotype generated by an activated UAS-p53 transgene. By DEP insertions, 7 genes were identified, which suppressed the p53-induced apoptosis. In 4 mutants, the suppression effect resulted from single genes activated by 1 UAS promoter (Pka-R2, Rga, crol, and Spt5). In the other 3 (Orct2, Polr2M, and stg), deleting either UAS promoter eliminated the suppression effect. In qPCR experiments, we found that the genes in the vicinity of the DEP insertion also showed an elevated expression level. This suggested an additive effect of the nearby genes on suppressing apoptosis. In the eukaryotic genomes, there are coexpressed gene clusters. Three of the DEP insertion mutants are included, and 2 are in close vicinity of separate coexpressed gene clusters. This raises the possibility that the activity of some of the genes in these clusters may help the suppression of the apoptotic cell death.

• Klíčová slova
• Drosophila, activating insertional mutagenesis, apoptosis, p53, suppression,
• MeSH
• apoptóza * MeSH
• dominantní geny MeSH
• Drosophila melanogaster * genetika   MeSH
• fenotyp MeSH
• inzerční mutageneze * metody   MeSH
• nádorový supresorový protein p53 * genetika   metabolismus   MeSH
• promotorové oblasti (genetika) MeSH
• proteiny Drosophily * genetika   metabolismus   MeSH
• supresorové geny MeSH
• transpozibilní elementy DNA MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• nádorový supresorový protein p53 * MeSH
• p53 protein, Drosophila MeSH Prohlížeč
• proteiny Drosophily * MeSH
• transpozibilní elementy DNA MeSH

Green leaf volatiles (GLVs) are short-chain oxylipins that are emitted from plants in response to stress. Previous studies have shown that oral secretions (OS) of the tobacco hornworm Manduca sexta, introduced into plant wounds during feeding, catalyze the re-arrangement of GLVs from Z-3- to E-2-isomers. This change in the volatile signal however is bittersweet for the insect as it can be used by their natural enemies, as a prey location cue. Here we show that (3Z):(2E)-hexenal isomerase (Hi-1) in M. sexta's OS catalyzes the conversion of the GLV Z-3-hexenal to E-2-hexenal. Hi-1 mutants that were raised on a GLV-free diet showed developmental disorders, indicating that Hi-1 also metabolizes other substrates important for the insect's development. Phylogenetic analysis placed Hi-1 within the GMCβ-subfamily and showed that Hi-1 homologs from other lepidopterans could catalyze similar reactions. Our results indicate that Hi-1 not only modulates the plant's GLV-bouquet but also functions in insect development.

• MeSH
• fylogeneze MeSH
• katalýza MeSH
• listy rostlin MeSH
• Manduca * MeSH
• tělesné tekutiny * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Concentrative nucleoside transporters (Cnts) are unidirectional carriers that mediate the energy-costly influx of nucleosides driven by the transmembrane sodium gradient. Cnts are transmembrane proteins that share a common structural organization and are found in all phyla. Although there have been studies on Cnts from a biochemical perspective, no deep research has examined their role at the organismal level. Here, we investigated the role of the Drosophila melanogaster cnt1 gene, which is specifically expressed in the testes. We used the CRISPR/Cas9 system to generate a mutation in the cnt1 gene. The cnt1 mutants exhibited defects in the duration of copulation and spermatid maturation, which significantly impaired male fertility. The most striking effect of the cnt1 mutation in spermatid maturation was an abnormal structure of the sperm tail, in which the formation of major and minor mitochondrial derivatives was disrupted. Our results demonstrate the importance of cnt1 in male fertility and suggest that the observed defects in mating behavior and spermatogenesis are due to alterations in nucleoside transport and associated metabolic pathways.

• Klíčová slova
• adenosine, cnt1, copulation, gamete, male fertility, mitochondria, spermatogenesis, testis,
• Publikační typ
• časopisecké články MeSH

Adenosine (Ado) is an important signaling molecule involved in stress responses. Studies in mammalian models have shown that Ado regulates signaling mechanisms involved in "danger-sensing" and tissue-protection. Yet, little is known about the role of Ado signaling in Drosophila. In the present study, we observed lower extracellular Ado concentration and suppressed expression of Ado transporters in flies expressing mutant huntingtin protein (mHTT). We altered Ado signaling using genetic tools and found that the overexpression of Ado metabolic enzymes, as well as the suppression of Ado receptor (AdoR) and transporters (ENTs), were able to minimize mHTT-induced mortality. We also identified the downstream targets of the AdoR pathway, the modifier of mdg4 (Mod(mdg4)) and heat-shock protein 70 (Hsp70), which modulated the formation of mHTT aggregates. Finally, we showed that a decrease in Ado signaling affects other Drosophila stress reactions, including paraquat and heat-shock treatments. Our study provides important insights into how Ado regulates stress responses in Drosophila.

• Klíčová slova
• cytotoxicity, equilibrative nucleoside transporter, heat-shock protein 70, modifier of mdg4, mutant huntingtin, neurodegeneration,
• Publikační typ
• časopisecké články MeSH

Insect adipokinetic hormones (AKHs) are short peptides produced in the corpora cardiaca and are responsible for mobilizing energy stores from the fat body to the hemolymph. Three related peptides, AKH1, AKH2, and AKH/corazonin-related peptide (ACP) as well as three AKH receptors have been reported in Bombyx mori. AKH1 and AKH2 are specific for the AKHR1 receptor, whereas ACP interacts with the other two AKHRs. To assess the effect of the two silkworm AKHs and ACP in the regulation of energy homeostasis we examined the expression pattern of the three peptides and their receptors as well as their effect on the level of carbohydrates and lipids in the hemolymph. Our results support the hypothesis that only AKH1 and AKH2 peptides together with the AKHR1 receptor are involved in the maintenance of energy homeostasis. Because Bombyx AKHR1 (BmAKHR1) seems to be a true AKHR we generated its mutation. The BmAKHR1 mutant larvae display significantly lower carbohydrate and lipid levels in the hemolymph and reduced sensitivity to starvation. Our study clarifies the role of BmAKHR1 in energy homeostasis.

• Klíčová slova
• BMSK0010951, Bommo-AKH1, Bommo-AKH2, NM_001043584, TALEN, silkworm, targeted mutagenesis,
• MeSH
• bourec růst a vývoj   metabolismus   MeSH
• energetický metabolismus MeSH
• hemolymfa metabolismus   MeSH
• hmyzí hormony genetika   metabolismus   MeSH
• hmyzí proteiny genetika   metabolismus   MeSH
• kyselina pyrrolidonkarboxylová analogy a deriváty   metabolismus   MeSH
• larva metabolismus   MeSH
• lipidy analýza   MeSH
• mutageneze MeSH
• neuropeptidy genetika   metabolismus   MeSH
• oligopeptidy genetika   metabolismus   MeSH
• protein - isoformy genetika   metabolismus   MeSH
• receptory glukagonu genetika   metabolismus   MeSH
• regulace genové exprese MeSH
• sacharidy analýza   MeSH
• signální transdukce * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adipokinetic hormone MeSH Prohlížeč
• corazonin protein, insect MeSH Prohlížeč
• hmyzí hormony MeSH
• hmyzí proteiny MeSH
• kyselina pyrrolidonkarboxylová MeSH
• lipidy MeSH
• neuropeptidy MeSH
• oligopeptidy MeSH
• protein - isoformy MeSH
• receptory glukagonu MeSH
• sacharidy MeSH

Plants and pollinators are mutually beneficial: plants provide nectar as a food source and in return their pollen is disseminated by pollinators such as honeybees. Some plants secrete chemicals to deter herbivores as a protective measure, among which is caffeine, a naturally occurring, bitter tasting, and pharmacologically active secondary compound. It can be found in low concentrations in the nectars of some plants and as such, when pollinators consume nectar, they also take in small amounts of caffeine. Whilst caffeine has been indicated as an antioxidant in both mammals and insects, the effect on insect immunity is unclear. In the present study, honeybees were treated with caffeine and the expression profiles of genes involved in immune responses were measured to evaluate the influence of caffeine on immunity. In addition, honeybees were infected with deformed wing virus (DWV) to study how caffeine affects their response against pathogens. Our results showed that caffeine can increase the expression of genes involved in immunity and reduce virus copy numbers, indicating that it has the potential to help honeybees fight against viral infection. The present study provides a valuable insight into the mechanism by which honeybees react to biotic stress and how caffeine can serve as a positive contributor, thus having a potential application in beekeeping.

• Klíčová slova
• caffeine, deformed wing virus (DWV), honeybee, immune gene,
• Publikační typ
• časopisecké články 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.

• Klíčová slova
• Bombyx mori, Spodoptera frugiperda, adenosine signaling, baculovirus, gloverin, glycolysis,
• 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
• Názvy látek
• adenosin MeSH
• adenosintrifosfát MeSH
• deoxyglukosa MeSH
• gloverin MeSH Prohlížeč
• hmyzí proteiny MeSH
• mezibuněčné signální peptidy a proteiny MeSH
• purinergní receptory P1 MeSH

The pathogenic effect of mutant HTT (mHTT) which causes Huntington disease (HD) are not restricted to nervous system. Such phenotypes include aberrant immune responses observed in the HD models. However, it is still unclear how this immune dysregulation influences the innate immune response against pathogenic infection. In the present study, we used transgenic Drosophila melanogaster expressing mutant HTT protein (mHTT) with hemocyte-specific drivers and examined the immune responses and hemocyte function. We found that mHTT expression in the hemocytes did not affect fly viability, but the numbers of circulating hemocytes were significantly decreased. Consequently, we observed that the expression of mHTT in the hemocytes compromised the immune responses including clot formation and encapsulation which lead to the increased susceptibility to entomopathogenic nematode and parasitoid wasp infections. In addition, mHTT expression in Drosophila macrophage-like S2 cells in vitro reduced ATP levels, phagocytic activity and the induction of antimicrobial peptides. Further effects observed in mHTT-expressing cells included the altered production of cytokines and activation of JAK/STAT signaling. The present study shows that the expression of mHTT in Drosophila hemocytes causes deficient cellular and humoral immune responses against invading pathogens. Our findings provide the insight into the pathogenic effects of mHTT in the immune cells.

• Klíčová slova
• Drosophila melanogaster, Huntington's disease, antimicrobial peptide (AMPs), cytokines, immunity, infection, phagocytosis,
• MeSH
• buněčné linie MeSH
• Drosophila melanogaster MeSH
• exprese genu * MeSH
• geneticky modifikovaná zvířata MeSH
• hemocyty imunologie   MeSH
• humorální imunita * MeSH
• lidé MeSH
• protein huntingtin genetika   imunologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• HTT protein, human MeSH Prohlížeč
• protein huntingtin MeSH

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
• Názvy látek
• histony MeSH
• hmyzí proteiny MeSH
• mikro RNA MeSH
• Pag1 protein, Heliothis zea virus 1 MeSH Prohlížeč
• RNA virová MeSH
• virové proteiny MeSH

RNA interference (RNAi) has been widely applied for uncovering the biological functions of numerous genes, and has been envisaged as a pest control tool operating by disruption of essential gene expression. Although different methods, such as injection, feeding, and soaking, have been reported for successful delivery of double-stranded RNA (dsRNA), the efficiency of RNAi through oral delivery of dsRNA is highly variable among different insect groups. The German cockroach, Blattella germanica, is highly sensitive to the injection of dsRNA, as shown by many studies published previously. The present study describes a method to demonstrate that the dsRNA encapsulated with liposome carriers is sufficient to retard the degradation of dsRNA by midgut juice. Notably, the continuous feeding of dsRNA encapsulated by liposomes significantly reduces the tubulin expression in the midgut, and led to the death of cockroaches. In conclusion, the formulation and utilization of dsRNA lipoplexes, which protect dsRNA against nucleases, could be a practical use of RNAi for insect pest control in the future.

• MeSH
• dvouvláknová RNA metabolismus   MeSH
• hmyz genetika   MeSH
• liposomy metabolismus   MeSH
• RNA interference fyziologie   MeSH
• švábi genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• audiovizuální média MeSH
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• dvouvláknová RNA MeSH
• liposomy MeSH