Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.512
Filtrar
1.
Soft Matter ; 17(34): 7817-7821, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34612350

RESUMO

Bombyx (B.) mori silk's water-responsive actuation correlates to its high ß-sheet crystallinity. In this research, we demonstrated that stiff silica nanoparticles can mimic the role of dispersed ß-sheet nanocrystals and dramatically increase amorphous silk's water-responsive actuation energy density to ∼700 kJ m-3.


Assuntos
Bombyx , Nanopartículas , Animais , Dióxido de Silício , Seda , Água
2.
ACS Biomater Sci Eng ; 7(9): 4626-4636, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34469125

RESUMO

Sericin has become a promising natural anti-inflammatory protein. However, the biological functions of sericins largely depend on their origins; no study has yet been carried out to comparatively investigate the therapeutic effects of sericins from different sources against inflammatory diseases. Herein, we extracted and purified three kinds of sericins, namely silkworm sericin (SS), tussah sericin (TS), and castor silk sericin (CSS). These sericins showed negligible cytotoxicities against colitis-associated cells (colon epitheliums and activated macrophages). Further investigations displayed that these sericins could remarkably downregulate the secreted amounts of TNF-α, promote the recovery of the damaged colonic epithelial barrier, and eliminate endogenous reactive oxygen species in Raw 264.7 macrophages and Caenorhabditis elegans. In vivo experiments demonstrated that chitosan/alginate hydrogel-encapsulating SS could achieve efficient accumulation of SS in the colitis tissues and thereby play a more effective role in relieving ulcerative colitis (UC) than TS and CSS. Our findings collectively demonstrate that SS can be extracted, formulated, and used as a robust therapeutic agent for the oral treatment of UC.


Assuntos
Bombyx , Colite Ulcerativa , Sericinas , Animais , Colite Ulcerativa/tratamento farmacológico , Hidrogéis
3.
Zool Res ; 42(5): 637-649, 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34472225

RESUMO

The insect brain is the central part of the neurosecretory system, which controls morphology, physiology, and behavior during the insect's lifecycle. Lepidoptera are holometabolous insects, and their brains develop during the larval period and metamorphosis into the adult form. As the only fully domesticated insect, the Lepidoptera silkworm Bombyx mori experienced changes in larval brain morphology and certain behaviors during the domestication process. Hormonal regulation in insects is a key factor in multiple processes. However, how juvenile hormone (JH) signals regulate brain development in Lepidoptera species, especially in the larval stage, remains elusive. We recently identified the JH receptor Methoprene tolerant 1 ( Met1) as a putative domestication gene. How artificial selection on Met1 impacts brain and behavioral domestication is another important issue addressing Darwin's theory on domestication. Here, CRISPR/Cas9-mediated knockout of Bombyx Met1 caused developmental retardation in the brain, unlike precocious pupation of the cuticle. At the whole transcriptome level, the ecdysteroid (20-hydroxyecdysone, 20E) signaling and downstream pathways were overactivated in the mutant cuticle but not in the brain. Pathways related to cell proliferation and specialization processes, such as extracellular matrix (ECM)-receptor interaction and tyrosine metabolism pathways, were suppressed in the brain. Molecular evolutionary analysis and in vitro assay identified an amino acid replacement located in a novel motif under positive selection in B. mori, which decreased transcriptional binding activity. The B. mori MET1 protein showed a changed structure and dynamic features, as well as a weakened co-expression gene network, compared with B. mandarina. Based on comparative transcriptomic analyses, we proposed a pathway downstream of JH signaling (i.e., tyrosine metabolism pathway) that likely contributed to silkworm larval brain development and domestication and highlighted the importance of the biogenic amine system in larval evolution during silkworm domestication.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Bombyx/metabolismo , Proteínas de Insetos/metabolismo , Hormônios Juvenis/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Bombyx/crescimento & desenvolvimento , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Sistemas CRISPR-Cas , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Proteínas de Insetos/genética , Tegumento Comum/fisiologia , Larva/crescimento & desenvolvimento , Larva/metabolismo , Filogenia , Conformação Proteica
4.
Acta Virol ; 65(3): 264-272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34565154

RESUMO

Apoptosis is a characteristic feature of a nucleopolyhedrovirus infected insect cells. This defensive strategy of the insect cells also affects the viral infectivity. On the contrary, the P35 baculovirus apoptosis inhibitor impedes the insect cell apoptosis induced by viral infection. Our previous investigation of the Bombyx mori nucleopolyhedrovirus (BmNPV) acetylome showed that 3 lysine (K) (70, 127 and 256) sites of P35 were acetylated during infection. How these modifications affect the interaction between the insect cells and BmNPV is still unknown. In order to explore the underlying mechanism of P35 lysine acetylation, mutants with glutamine or arginine substitution were constructed to mimic the acetylated (Q) and deacetylated (R) state. ELISA and DNA fragmentation assay were used to ascertain the acetylation effects on apoptosis. Subsequently the results showed that acetylation of K70 upregulated the anti-apoptotic activity, thereby preventing apoptosis induced by insect cells. Caspase 1 activity assay further confirmed that, acetylated K70 exhibited a strong anti-apoptotic activity in cell lines infected with BmNPV. Intriguingly, an examination with the yeast 2 hybrid (Y2H) assay revealed an interaction with the silkworm caspase 1. Taken together, we demonstrated that acetylation of P35 is crucial for an interaction with caspase 1 and the upregulation of anti-apoptotic activity. Keywords: Bombyx mori; BmNPV; P35; acetylation; anti-apoptotic; caspase 1.


Assuntos
Bombyx , Nucleopoliedrovírus , Acetilação , Animais , Apoptose , Linhagem Celular , Nucleopoliedrovírus/genética
5.
J Phys Chem Lett ; 12(37): 8956-8962, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34505773

RESUMO

Gold nanoparticles (Au NPs) have good biocompatibility and special quantum effects. In this Letter, we embedded Au NPs into silkworm hemolymph (SH) to improve the performance of the device and fabricated Al/SH:Au NPs/indium tin oxide (ITO)/glass resistive random access memory. The device exhibits a bipolar switching behavior with a retention time of 104 s. Compared with the Al/SH/ITO device without Au NPs, the device has a higher ON/OFF current ratio (>105) and a smaller Vreset. The improvement in device performance is attributed to the fact that Au NPs act as the electron-trapping center in the device; a Coulomb blockade occurs after electrons are trapped, thereby increasing the resistance of the device in the high-resistance state. Using optimized devices can realize multilevel data storage and can also simulate synaptic characteristics such as potentiation and depression. The device is expected to be applied to high-density, low-cost, degradable, and biocompatible storage devices and neuromorphic computing in the future.


Assuntos
Ouro/química , Armazenamento e Recuperação da Informação , Nanopartículas Metálicas/química , Sinapses/fisiologia , Animais , Bombyx/metabolismo , Elétrons , Vidro/química , Hemolinfa/química , Compostos de Estanho/química
6.
J Insect Sci ; 21(4)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34401920

RESUMO

Glycosylation is one of the most common post-translational modifications to occur during protein biosynthesis, but remains poorly understood in insects. In this study, we collected serum proteins from two silkworm developmental stages, namely day 7 of the fifth instar larval stage and day 2 of the pupal stage. Results of SDS-PAGE and periodic acid-Schiff staining revealed that most serum proteins with high abundance were putative glycoproteins. LC-MS/MS identified 149 larval and 303 pupal serum proteins in the Con A lectin-enriched fractions. GO analysis revealed that many serum proteins were involved in the proteolysis and carbohydrate metabolic process. 82 N-linked glycoproteins with at least one glycosylation site were identified. N-Linked glycosylation occurred at the sequon, Asn-X-Ser/Thr, and the proportions of Ser and Thr glycosylation at the hydroxy position were found 39.6% and 60.3%, respectively. The N-glycan structures found in serum glycoproteins were mainly Man2FucGlcNAc2 (67.9%). Since storage protein 1 and transferrin had a relatively high abundance in the serum and could be significantly enriched by Con A lectin, their glycosylation was analyzed in detail. Glycoside hydrases, serine proteases and serpins were found to form three interacting glycoprotein networks using the website STRING. This study provides important clues for the understanding of the function of N-linked glycosylation in metabolism, immunity, and metamorphosis.


Assuntos
Bombyx/metabolismo , Glicoproteínas/metabolismo , Receptores de Concanavalina A/metabolismo , Animais , Cromatografia de Afinidade , Glicosilação , Proteínas de Insetos/metabolismo , Espectrometria de Massas , Proteômica , Transferrina/metabolismo
7.
Pestic Biochem Physiol ; 178: 104923, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34446199

RESUMO

Cell division cycle protein 37 (Cdc37) is a molecular chaperone that actively participates in many intracellular physiological and biochemical processes as well as pathogen infection. However, the function of Cdc37 in silkworm cells under Bombyx mori nucleopolyhedrovirus (BmNPV) infection is unknown. We cloned and identified BmCdc37, a Cdc37 gene from B. mori, which is highly conserved among other species. After BmNPV infection, the expression level of the BmCdc37 gene was up-regulated and showed an expression pattern similar to the BmHsp90 gene, which relies on Cdc37 to stabilize and activate specific protein kinases. The immunofluorescence, bimolecular fluorescence complementation (BiFC), and co-immunoprecipitation (Co-IP) assays all indicated that BmCdc37 interacts with BmHsp90 in silkworm cells. Both BmCdc37 and BmHsp90 promote the reproduction of BmNPV. Co-expression of BmCdc37 and BmHsp90 was better at promoting virus proliferation than overexpression alone. These findings all indicate that BmCdc37 plays an active role in the proliferation of BmNPV.


Assuntos
Bombyx , Animais , Bombyx/genética , Proteínas de Ciclo Celular/genética , Proliferação de Células , Interações Hospedeiro-Patógeno , Proteínas de Insetos/genética , Nucleopoliedrovírus
8.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361011

RESUMO

Many lepidopteran larvae produce silk feeding shelters and cocoons to protect themselves and the developing pupa. As caterpillars evolved, the quality of the silk, shape of the cocoon, and techniques in forming and leaving the cocoon underwent a number of changes. The silk of Pseudoips prasinana has previously been studied using X-ray analysis and classified in the same category as that of Bombyx mori, suggesting that silks of both species have similar properties despite their considerable phylogenetic distance. In the present study, we examined P. prasinana silk using 'omics' technology, including silk gland RNA sequencing (RNA-seq) and a mass spectrometry-based proteomic analysis of cocoon proteins. We found that although the central repetitive amino acid sequences encoding crystalline domains of fibroin heavy chain molecules are almost identical in both species, the resulting fibers exhibit quite different mechanical properties. Our results suggest that these differences are most probably due to the higher content of fibrohexamerin and fibrohexamerin-like molecules in P. prasinana silk. Furthermore, we show that whilst P. prasinana cocoons are predominantly made of silk similar to that of other Lepidoptera, they also contain a second, minor silk type, which is present only at the escape valve.


Assuntos
Bombyx/genética , Evolução Molecular , Fibroínas/genética , Animais , Bombyx/classificação , Bombyx/metabolismo , Glândulas Exócrinas/metabolismo , Fibroínas/química , Filogenia , Proteoma/genética , Proteoma/metabolismo , Transcriptoma
9.
Zoolog Sci ; 38(4): 305-310, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34342950

RESUMO

To clarify the molecular mechanism of prevention of entry into diapause in Bombyx mori by HCl treatment, we biochemically analyzed calcineurin regulatory B subunit (CNB) in diapause eggs treated with HCl solution. Our previous studies revealed that HCl treatment causes Ca2+ to efflux from diapause eggs. Therefore, we attempted to analyze CNB, which is known to associate with Ca2+. The gene expression level of CNB was increased by HCl treatment and the changes of the gene expression were almost the same as that in the non-diapause eggs. As for diapause eggs, almost no gene expression of CNB was confirmed except just after oviposition. In the assay for phosphorylation by protein kinase CK2, recombinant CNB (rCNB) was phosphorylated in vitro. Additionally, a Ca2+ binding assay indicated that rCNB shows affinity for Ca2+. The distribution of CNB was investigated with an immunohistochemical technique using antiserum against rCNB in diapause eggs and HCl-treated diapause eggs. CNB was localized in serosa cells and yolk cells in both eggs. These data may suggest that CNB is activated by intracellular Ca2+ or efflux Ca2+ resulting from HCl treatment, and that it plays a role in the molecular mechanisms of artificial diapause prevention or the breaking of diapause in the silkworm.


Assuntos
Bombyx/fisiologia , Calcineurina/metabolismo , Diapausa , Proteínas de Insetos/metabolismo , Subunidades Proteicas/metabolismo , Animais , Bombyx/efeitos dos fármacos , Bombyx/genética , Calcineurina/química , Calcineurina/genética , Cálcio/metabolismo , Diapausa/efeitos dos fármacos , Regulação da Expressão Gênica , Ácido Clorídrico/farmacologia , Imuno-Histoquímica , Proteínas de Insetos/química , Proteínas de Insetos/genética , Óvulo/metabolismo , Fosforilação , Análise Serial de Proteínas , Subunidades Proteicas/química , Subunidades Proteicas/genética , Distribuição Tecidual
10.
Arch Insect Biochem Physiol ; 108(2): e21839, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34427962

RESUMO

Flavonoids are secondary metabolites that help plants resist insect attack. It can resist insect attack by inhibiting insect immune defense, and pathogens can also inhibit insect immune defense. It is speculated that the combination of flavonoids and pathogens may inhibit the immune defense and have stronger toxicity to silkworm. In this study, the combined treatment of quercetin with Bombyx mori nuclear polyhedrosis virus (BmNPV) had significant negative effects on the growth and survival of silkworm compared with BmNPV group. The detoxifying enzyme activity of BmNPV group was significantly increased at 96 h, while the activity of the combined treatment group was significantly decreased with the increase of quercetin exposure time (72 or 96 h). The activity of antioxidant enzymes also showed a similar trend, that was, the activity of antioxidant enzymes in the combined treatment group also decreased significantly with the increase of quercetin exposure time, which led to the increase of reactive oxygen species content. The silkworm cells would produce lipid peroxidation, malondialdehyde content was significantly increased, so that the expression of immune-related genes (the antimicrobial peptide, Toll pathway, IMD pathway, JAK-STAT pathway, and melanin genes) were decreased, leading to the damage of the immune system of silkworm. These results indicated that quercetin combined with BmNPV could inhibit the activities of protective enzymes and lead to oxidative damage to silkworm. It can also affect the immune response of the silkworm, and thus resulting in abnormal growth. This study provides the novel conclusion that quercetin accumulation will increase the susceptibility of silkworm to pathogens.


Assuntos
Bombyx , Quercetina/farmacologia , Animais , Antioxidantes/metabolismo , Bombyx/efeitos dos fármacos , Bombyx/crescimento & desenvolvimento , Bombyx/imunologia , Bombyx/virologia , Imunidade/efeitos dos fármacos , Desentoxicação Metabólica Fase I/imunologia , Nucleopoliedrovírus/imunologia , Espécies Reativas de Oxigênio/metabolismo
11.
Arch Insect Biochem Physiol ; 108(2): e21838, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34350621

RESUMO

Silkworm is not only an ideal insect model with a biological significance, but it is also crucially important in sericulture and bioreactors. Bombyx mori nucleopolyhedrovirus (BmNPV) is a principal pathogen of silkworm. However, the molecular mechanism underlying BmNPV invasion is still unclear. Based on our previous acetylome research findings of B. mori after BmNPV infection, here, we focused on silkworm alteration/deficiency in activation-3 (BmAda3). The acetylation of K124 and K128 were significantly reduced (0.66-fold) upon the virus challenge. Due to the interaction between Ada3 and P53, acetylation-mimic K124Q/K128Q and deacetylation-mimic K124R/K128R mutants of BmAda3 were constructed to explore the roles exerted by the acetylation modification of BmAda3 on P53. Yeast two-hybrid and IP results revealed that both BmAda3 and its deacetylation mutants (K124R/K128R) interacted with P53. Interestingly, we found that the deacetylation mutants (K124R/K128R) of BmAda3 significantly promoted the stability of P53. Since P53 is a proapoptotic factor, cell apoptosis was detected. We established that the deacetylation of BmAda3 at K124/K128 facilitated cellular apoptosis during BmNPV infection. Finally, viral proliferation was analyzed, and the results indicated that virus generation was reduced by K124/K128 deacetylation. Our report, based on the deacetylation of two lysine sites 124/128 of BmAda3, shows possible regulatory pathways of BmNPV proliferation and provides novel insights into the development of antiviral agents.


Assuntos
Apoptose , Bombyx/virologia , Histona Acetiltransferases , Nucleopoliedrovírus/patogenicidade , Proteína Supressora de Tumor p53/metabolismo , Animais , Bombyx/genética , Bombyx/metabolismo , Genes de Insetos , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Interações Hospedeiro-Patógeno , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Mutação
12.
Molecules ; 26(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361802

RESUMO

Recently, Bombyx mori silk fibroin (SF) has been shown to be a suitable material for vascular prostheses for small arteries. In this study, we developed a softer SF graft by coating water-dispersed biodegradable polyurethane (PU) based on polycaprolactone and an SF composite sponge on the knitted SF vascular graft. Three kinds of 13C solid-state nuclear magnetic resonance (NMR), namely carbon-13 (13C) cross-polarization/magic angle spinning (MAS), 13C dipolar decoupled MAS, and 13C refocused insensitive nuclei enhanced by polarization transfer (r-INEPT) NMR, were used to characterize the PU-SF coating sponge. Especially the 13C r-INEPT NMR spectrum of water-dispersed biodegradable PU showed that both main components of the non-crystalline domain of PU and amorphous domain of SF were highly mobile in the hydrated state. Then, the small-diameter SF artificial vascular grafts coated with this sponge were evaluated through implantation experiments with rats. The implanted PU-SF-coated SF grafts showed a high patency rate. It was confirmed that the inside of the SF grafts was covered with vascular endothelial cells 4 weeks after implantation. These results showed that the water-dispersed biodegradable PU-SF-coated SF graft created in this study could be a strong candidate for small-diameter artificial vascular graft.


Assuntos
Prótese Vascular , Fibroínas/química , Poliuretanos/química , Seda/química , Animais , Bombyx/química , Células Endoteliais/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Teste de Materiais , Poliuretanos/farmacologia , Ratos , Seda/farmacologia , Tecidos Suporte/química , Água/química
13.
Environ Pollut ; 289: 117866, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343750

RESUMO

The neonicotinoid insecticide acetamiprid is widely applied for pest control in agriculture production, and its exposure often results in adverse effects on a non-target insect, Bombyx mori. However, only few studies have investigated the effects of exposure to sublethal doses of neonicotinoid insecticides on gut microbiota and susceptibility to pathogenic bacteria. In this study, we aimed to explore the possible mechanisms underlying the acetamiprid-induced compositional changes in gut microbiota of silkworm and reduced host resistance against detrimental microbes. This study indicated that sublethal dose of acetamiprid activated the dual oxidase-reactive oxygen species (Duox-ROS) system and induced ROS accumulation, leading to dysregulation of intestinal immune signaling pathways. The evenness and structure of bacterial community were altered. Moreover, after 96 h of exposure to sublethal dose of acetamiprid, several bacteria, such as Pseudomonas sp (Biotype A, DOP-1a, XW34) and Staphylococcus sp (RCB1054, RCB314, X302), invaded the silkworm hemolymph. The survival rate and bodyweight of the acetamiprid treated silkworm larvae inoculated with Enterobacter cloacae (E. cloacae) were significantly lower than the acetamiprid treatment group, suggesting that acetamiprid reduced silkworm resistance against pathogens. These findings indicated that acetamiprid disturbed gut microbial homeostasis of Bombyx mori, resulting in changes in gut microbial community and susceptibility to detrimental microbes.


Assuntos
Bombyx , Animais , Bactérias , Homeostase , Neonicotinoides/toxicidade
14.
Appl Microbiol Biotechnol ; 105(14-15): 6019-6031, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34324010

RESUMO

Claudin-2 is a major component of tight junctions (TJs), which play an important role in reovirus entry into host cells. The Bombyx mori cytoplasmic polyhedosis virus (BmCPV) relates to the cypovirus strain of the reovirus family. So far, the role of claudin-2 in the process of BmCPV infection is not known. In the present study, it was observed that increasing expression of the claudin-2 gene (CLDN2) may concomitantly elevate BmCPV infection. Contrarily, knockdown of CLDN2 expression by siRNAs can reduce BmCPV infection. Similarly, antibody-based blockage of claudin-2 could also decrease BmCPV cell entry. These results suggest that claudin-2 can promote BmCPV infection in vitro. Moreover, immunofluorescence (IF) assays showed that claudin-2 can interact with BmCPV during viral infection. Specifically, co-immunoprecipitation experiments indicated that claudin-2 binds the BmCPV VP7 (instead of VP3 proteins). The interaction between VP7 and claudin-2 was further confirmed by bimolecular fluorescence complementation (BIFC). Altogether, our results suggest that BmCPV cell entry can be promoted upon interaction of VP7 with claudin-2. These findings provide new mechanistic insights related to BmCPV infection. KEY POINTS: •Claudin-2 could promote BmCPV infection of cells. •Claudin-2 interacted with BmCPV during BmCPV infection. •Claudin-2 could interact with BmCPV VP7 protein, but not with VP3 proteins.


Assuntos
Bombyx , Reoviridae , Animais , Claudina-2 , Claudinas/genética , Interações Hospedeiro-Patógeno , Proteínas de Insetos , Internalização do Vírus , Proteína da Zônula de Oclusão-2
15.
Arch Insect Biochem Physiol ; 108(1): e21832, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34250644

RESUMO

Autophagy is a critical mechanism for the self-renewal, proliferation, and differentiation of stem cells. Bombyx mori midgut has stem cells that play a role in the regeneration of the larval epithelium in larval stages and the formation of the pupal midgut epithelium during larval-pupal metamorphosis. In this study, the role of the autophagy mechanism in midgut stem cells during the formation of the pupal midgut was investigated. For this purpose, two different doses of autophagy inhibitor chloroquine were administered to B. mori larvae on days 7 and 8 of the fifth larval stage. Morphological changes during the formation process of the pupal epithelium, expression levels of autophagy-related genes Atg8 and Atg12 in stem cells, and the amounts of lysosomal enzyme acid phosphatase were determined after the application. The obtained findings were evaluated in comparison with the control groups. Abnormalities in the formation of the pupal midgut after inhibition of autophagy showed the significance of the autophagy mechanism during this period.


Assuntos
Autofagia , Bombyx , Intestinos , Metamorfose Biológica/fisiologia , Células-Tronco , Fosfatase Ácida/efeitos dos fármacos , Fosfatase Ácida/metabolismo , Animais , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Bombyx/citologia , Bombyx/metabolismo , Bombyx/fisiologia , Cloroquina/farmacologia , Intestinos/citologia , Intestinos/efeitos dos fármacos , Larva/citologia , Larva/metabolismo , Pupa/citologia , Pupa/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
16.
Arch Insect Biochem Physiol ; 108(1): e21764, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34272769

RESUMO

Melanization is mediated by the prophenoloxidase (proPO) activation cascade and plays an important role in the arthropods immune system. Previously, we found that the hemolymph of the p50 strain does not perform melanization after infection with Autographa californica multiple nucleopolyhedrovirus (AcMNPV). However, this mechanism is still unclear. In this study, the underlying mechanism of the inhibition of hemolymph melanization was investigated by analysing the AcMNPV-susceptible or -resistant silkworm strains after inoculation with AcMNPV. The results showed that the level of hemolymph melanization was higher in resistant strain C108 than in susceptible strain p50 at the late stage (72 to 120 h postinoculation). The PO activity decreased significantly at the late stage of infection (72 to 120 hpi), and the expression of BmPPO1 and BmPPO2 was downregulated in p50. However, the PO activity increased in the resistant strain C108, while the expression level of BmPPO1 and BmPPO2 displayed no significant changes. The expression of the BmPPAE gene was upregulated in two strains during viral infection. In addition, the hemolymph melanization can weaken the viral activity in vitro. Our results suggested that the silkworm hemolymph melanization response is related to defence against the AcMNPV infection.


Assuntos
Bombyx , Imunidade , Melaninas/metabolismo , Nucleopoliedrovírus/imunologia , Animais , Bombyx/imunologia , Bombyx/virologia , Hemolinfa/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Viroses/veterinária
17.
Int J Mol Sci ; 22(14)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34299043

RESUMO

Bombyx mori nucleopolyhedrovirus (BmNPV) is a pathogen that causes great economic losses in sericulture. Many genes play a role in viral infection of silkworms, but silkworm metabolism in response to BmNPV infection is unknown. We studied BmE cells infected with BmNPV. We performed liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS)-based non-targeted metabolomics analysis of the cytosolic extract and identified 36, 76, 138, 101, 189, and 166 different molecules at 3, 6, 12, 24, 48, and 72 h post BmNPV infection (hpi) compared with 0 hpi. Compounds representing different areas of metabolism were increased in cells post BmNPV infection. These areas included purine metabolism, aminoacyl-tRNA biosynthesis, and ABC transporters. Glycerophosphocholine (GPC), 2-hydroxyadenine (2-OH-Ade), gamma-glutamylcysteine (γ-Glu-Cys), hydroxytolbutamide, and 5-pyridoxolactone glycerophosphocholine were continuously upregulated in BmE cells post BmNPV infection by heat map analysis. Only 5-pyridoxolactone was found to strongly inhibit the proliferation of BmNPV when it was used to treat BmE cells. Fewer infected cells were detected and the level of BmNPV DNA decreased with increasing 5-pyridoxolactone in a dose-dependent manner. The expression of BmNPV genes ie1, helicase, GP64, and VP39 in BmE cells treated with 5-pyridoxolactone were strongly inhibited in the BmNPV infection stage. This suggested that 5-pyridoxolactone may suppress the entry of BmNPV. The data in this study characterize the metabolism changes in BmNPV-infected cells. Further analysis of 5-pyridoxolactone, which is a robust antiviral molecule, may increase our understanding of antiviral immunity.


Assuntos
Antivirais/farmacologia , Bombyx/crescimento & desenvolvimento , Lactonas/farmacologia , Metaboloma , Nucleopoliedrovírus/efeitos dos fármacos , Viroses/tratamento farmacológico , Animais , Bombyx/efeitos dos fármacos , Bombyx/virologia , Viroses/metabolismo , Viroses/virologia
18.
Nat Commun ; 12(1): 4498, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301931

RESUMO

In animal germlines, PIWI proteins and the associated PIWI-interacting RNAs (piRNAs) protect genome integrity by silencing transposons. Here we report the extensive sequence and quantitative correlations between 2',3'-cyclic phosphate-containing RNAs (cP-RNAs), identified using cP-RNA-seq, and piRNAs in the Bombyx germ cell line and mouse testes. The cP-RNAs containing 5'-phosphate (P-cP-RNAs) identified by P-cP-RNA-seq harbor highly consistent 5'-end positions as the piRNAs and are loaded onto PIWI protein, suggesting their direct utilization as piRNA precursors. We identified Bombyx RNase Kappa (BmRNase κ) as a mitochondria-associated endoribonuclease which produces cP-RNAs during piRNA biogenesis. BmRNase κ-depletion elevated transposon levels and disrupted a piRNA-mediated sex determination in Bombyx embryos, indicating the crucial roles of BmRNase κ in piRNA biogenesis and embryonic development. Our results reveal a BmRNase κ-engaged piRNA biogenesis pathway, in which the generation of cP-RNAs promotes robust piRNA production.


Assuntos
Endorribonucleases/genética , Perfilação da Expressão Gênica/métodos , Proteínas de Insetos/genética , RNA Interferente Pequeno/genética , RNA/genética , Animais , Sequência de Bases , Bombyx , Linhagem Celular , Endorribonucleases/metabolismo , Feminino , Proteínas de Insetos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mutação , Ácidos Fosfatídicos/química , RNA/química , RNA/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , RNA-Seq/métodos , Testículo/metabolismo
19.
Pestic Biochem Physiol ; 177: 104895, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34301357

RESUMO

(R)-Octopamine (OA), a major invertebrate biogenic amine, plays an important role in a wide variety of physiological processes as a neurohormone, neuromodulator, and neurotransmitter in insects. OA receptors (OARs) are class A G protein-coupled receptors that specifically bind OA to activate downstream signaling cascades by coupling to G proteins and presumably other regulatory proteins. These receptors are broadly classified as α- and ß-adrenergic-like OARs (α- and ß-ALOARs). OARs are considered important targets of insecticides and acaricides. In the present study, we examined the actions of an array of 13 heterocyclic OAR agonists with the moieties that correspond to the phenyl group and the basic nitrogen atom of OA on α- and ß-ALOARs from the silkworm (Bombyx mori) and the signaling pathways activated through these actions. The results indicated that these compounds display structure-dependent receptor subtype selectivity and G protein subtype preference, underscoring the need to determine which subtype and signaling pathway mediates toxicologically relevant effects for the efficient discovery of novel pest control chemicals. The results of insecticidal assays using B. mori larvae suggested that the activation of signal transduction pathways via α-ALOARs might be mainly responsible for the toxicological effects of the heterocycles.


Assuntos
Bombyx , Receptores de Amina Biogênica , Animais , Bombyx/genética , Bombyx/metabolismo , Proteínas de Ligação ao GTP , Octopamina , Receptores de Amina Biogênica/genética
20.
Pestic Biochem Physiol ; 177: 104899, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34301361

RESUMO

The silkworm, Bombyx mori (B. mori) is an important economic insect which ingests mulberry leaves and products the silk in industry. Chlorfenapyr is a new halogenated pyrrole insecticide which has been promoted for the control of mulberry insect pests in China. However, the detoxification mechanism of the silkworm to chlorfenapyr has not been investigated yet. In the present study, we first estimated the LC30 dose of chlorfenapyr for 3rd instar B. mori larvae, and then, in order to characterise the chlorfenapyr detoxification mechanism, the transcriptomes of chlorfenapyr-treated and untreated 3rd instar B. mori larvae were compared using RNA-sequencing. In total, 146, 533, 126 and 148, 957, 676 clean reads were obtained from insecticide-treated and control silkworm larvae, respectively, and these reads generated 10, 954 genes. The transcriptional profile of silkworm larvae was significantly influenced by chlorfenapyr treatment. A total of 1196 differentially expressed genes (DEGs) were identified in insecticide-treated and control B. mori larvae, in which 644 genes were upregulated and 552 genes were downregulated. Results showed that multiple DEGs were enriched in detoxication-related gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Eleven detoxifying enzyme genes which differentially expressed were screened, and their expression patterns were validated by qRT-PCR. Furthermore, we successfully knocked down all differentially upregulated detoxifying enzyme genes, and a bioassay showed that the mortality of chlorfenapyr-treated silkworm larvae was significantly higher after silencing these genes than in groups injected with dsGFP. The present study reveals the molecular basis of silkworm detoxification to chlorfenapyr exposure, and provides new insights into the management of insecticide damage in the silkworm.


Assuntos
Bombyx , Animais , Bombyx/genética , Bombyx/metabolismo , China , Perfilação da Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Piretrinas , Transcriptoma
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...