Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.823
Filtrar
1.
J Insect Sci ; 21(4)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34374763

RESUMO

The Coleoptera Scarabaeidae family is one of the most diverse groups of insects on the planet, which live in complex microbiological environments. Their immune systems have evolved diverse families of Host Defense Peptides (HDP) with strong antimicrobial and immunomodulatory activities. However, there are several peptide sequences that await discovery in this group of organisms. This would pave the way to identify molecules with promising therapeutic potential. This work retrieved two sources of information: 1) De-novo transcriptomic data from two species of neotropical Scarabaeidae (Dichotomius satanas and Ontophagus curvicornis); 2) Sequence data deposited in available databases. A Blast-based search was conducted against the transcriptomes with a subset of sequences representative of the HDP. This work reports 155 novel HDP sequences identified in nine transcriptomes from seven species of Coleoptera: D. satanas (n = 76; 49.03%), O. curvicornis (n = 23; 14.83%), (Trypoxylus dichotomus) (n = 18; 11.61%), (Onthophagus nigriventris) (n = 10; 6.45%), (Heterochelus sp) (n = 6; 3.87%), (Oxysternon conspicillatum) (n = 18; 11.61%), and (Popillia japonica) (n = 4; 2.58%). These sequences were identified based on similarity to known HDP insect families. New members of defensins (n = 58; 37.42%), cecropins (n = 18; 11.61%), attancins (n = 41; 26.45%), and coleoptericins (n = 38; 24.52%) were described based on their physicochemical and structural characteristics, as well as their sequence relationship to other insect HDPs. Therefore, the Scarabaeidae family is a complex and rich group of insects with a great diversity of antimicrobial peptides with potential antimicrobial activity.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Besouros/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/química , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Testes de Sensibilidade Microbiana , Conformação Proteica , Transcriptoma
2.
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
3.
J Phys Chem Lett ; 12(32): 7733-7737, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34355918

RESUMO

The supramolecular chirality of the hindwing of Anomala albopilosa (male) was investigated using a microscopic vibrational circular dichroism (VCD) system, denoted as MultiD-VCD. The source of intense infrared (IR) light for the system was a quantum cascade laser. Two-dimensional maps of IR and VCD spectra were taken by scanning the surface area (ca. 2 mm × 2 mm) of the insect hindwing tissue. The spectra ranged from 1500 to 1700 cm-1, and the maps have a spatial resolution of 100 µm. The distribution of proteins, including their supramolecular structures, was analyzed from the location-dependent spectral shape of the VCD bands assigned to amides I and II. The results revealed that the hindwing consists of segregated domains of proteins with different secondary structures: an α-helix (in one part of the membrane), a hybrid of α-helix and ß-sheet (in another part of the membrane), and a coil (in a vein).


Assuntos
Proteínas de Insetos/química , Asas de Animais/química , Animais , Dicroísmo Circular/métodos , Besouros , Masculino , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Estereoisomerismo , Vibração
4.
Food Chem ; 362: 130231, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34237653

RESUMO

The silkworm (Bombyx mori) is an important economic insect that can be used as food in many countries in Asia. However, silkworms and their metabolites are an important source of allergens, which can induce severe allergic reactions. So far, there are no systematic studies on the potential allergens in silkworm and its metabolites. These studies have important guiding significance for the prevention, diagnosis, and treatment of silkworm allergy. The aim of this study was to identify the potential allergens from larva, pupa, moth, silk, slough and feces of silkworm and analyze the sequence homology of silkworm allergens with other allergens identified in the Allergenonline database. We have found 45 potential allergens in silkworm. The results of the homology comparison suggested that silkworm allergens likely cross-react with those of Dermatophagoides farinae, Aedes aegypti, Tyrophagus putrescentiae, Triticum aestivum and Malassezia furfur.


Assuntos
Alérgenos/análise , Bombyx/química , Proteínas de Insetos/química , Alérgenos/metabolismo , Animais , Ásia , Bombyx/crescimento & desenvolvimento , Reações Cruzadas , Fezes/química , Hipersensibilidade , Proteínas de Insetos/análise , Proteínas de Insetos/metabolismo , Larva/química , Mariposas/química , Pupa/química , Seda/química
5.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204550

RESUMO

Recently, considerable attention has been paid to Bombyx mori silk fibroin by a range of scientists from polymer chemists to biomaterial researchers because it has excellent physical properties, such as strength, toughness, and biocompatibility. These appealing physical properties originate from the silk fibroin structure, and therefore, structural determinations of silk fibroin before (silk I) and after (silk II) spinning are a key to make wider applications of silk. There are discrepancies about the silk I structural model, i.e., one is type II ß-turn structure determined using many solid-state and solution NMR spectroscopies together with selectively stable isotope-labeled model peptides, but another is α-helix or partially α-helix structure speculated using IR and Raman methods. In this review, firstly, the process that led to type II ß-turn structure by the authors was introduced in detail. Then the problems in speculating silk I structure by IR and Raman methods were pointed out together with the problem in the assignment of the amide I band in the spectra. It has been emphasized that the conformational analyses of proteins and peptides from IR and Raman studies are not straightforward and should be very careful when the proteins contain ß-turn structure using many experimental data by Vass et al. In conclusion, the author emphasized here that silk I structure should be type II ß-turn, not α-helix.


Assuntos
Fibroínas/química , Fibroínas/metabolismo , Seda/química , Animais , Bombyx/química , Proteínas de Insetos/química , Espectroscopia de Ressonância Magnética/métodos , Peptídeos/química , Conformação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Seda/metabolismo , Espectrofotometria Infravermelho/métodos , Análise Espectral Raman/métodos
6.
Science ; 373(6554): 535-541, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326235

RESUMO

Interkingdom competition occurs between hymenopteran parasitoids and insect viruses sharing the same insect hosts. It has been assumed that parasitoid larvae die with the death of the infected host or as result of competition for host resources. Here we describe a gene family, parasitoid killing factor (pkf), that encodes proteins toxic to parasitoids of the Microgastrinae group and determines parasitism success. Pkfs are found in several entomopathogenic DNA virus families and in some lepidopteran genomes. We provide evidence of equivalent and specific toxicity against endoparasites for PKFs found in entomopoxvirus, ascovirus, baculovirus, and Lepidoptera through a mechanism that elicits apoptosis in the cells of susceptible parasitoids. This highlights the evolutionary arms race between parasitoids, viruses, and their insect hosts.


Assuntos
Entomopoxvirinae/fisiologia , Proteínas de Insetos/toxicidade , Lepidópteros/parasitologia , Lepidópteros/virologia , Proteínas Virais/toxicidade , Vespas/fisiologia , Animais , Apoptose , Evolução Biológica , Transferência Genética Horizontal , Genoma de Inseto , Interações Hospedeiro-Parasita , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Vírus de Insetos/fisiologia , Larva/genética , Larva/parasitologia , Larva/virologia , Lepidópteros/genética , Lepidópteros/metabolismo , Nucleopoliedrovírus/fisiologia , Spodoptera/genética , Spodoptera/metabolismo , Spodoptera/parasitologia , Spodoptera/virologia , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo , Vespas/crescimento & desenvolvimento
7.
Int J Biol Macromol ; 184: 721-730, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34174306

RESUMO

Aquaporin (AQP) transport solutes across cell membranes in both unicellular and multicellular organisms. In this study, the aquaporin CsPrip was identified in Chilo suppressalis, an important pest of rice. CsPrip was comprised of two variants, CsPrip_v1 and CsPrip_v2; the former variant was <103 bp was shorter than the latter, although both exhibited the same open reading frame (ORF). Transmembrane topology and protein structure analyses showed that CsPrip retained the conserved features of water-selective insect AQPs, including six transmembrane domains, two conserved hydrophobic asparagine-proline-alanine motifs and the aromatic/arginine constriction region. Expression in Xenopus oocytes revealed that CsPrip preferentially transported water and urea instead of trehalose and glycerol. The CsPrip transcript was expressed in multiple organs and tissues of C. suppressalis larvae and was most abundant in the hindgut and Malpighian tubules. CsPrip transcription was highest in male adults and was relatively stable throughout development. CsPrip expression in larvae was significantly altered by thermal stress, and relative humidity levels impacted CsPrip transcription in 3rd and 5th instar larvae. This study confirms that the aquaporin CsPrip performs multiple critical functions in maintaining water equilibrium in C. suppressalis.


Assuntos
Aquaporinas/genética , Aquaporinas/metabolismo , Lepidópteros/metabolismo , Oryza/parasitologia , Processamento Alternativo , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Aquaporinas/química , Feminino , Regulação da Expressão Gênica , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Lepidópteros/genética , Masculino , Modelos Moleculares , Especificidade de Órgãos , Conformação Proteica , Domínios Proteicos , Caracteres Sexuais , Ureia/metabolismo , Água/metabolismo , Xenopus/genética , Xenopus/crescimento & desenvolvimento
8.
Biochimie ; 187: 131-143, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34082040

RESUMO

SGTs (small glutamine-rich TPR-containing proteins) are dimeric proteins that belong to the class of co-chaperones characterized by the presence of TPR domains (containing tetratricopeptide repeats). Human (SGTA) and yeast (Sgt2) SGTs are characterized by three distinct domains: an N-terminal dimerization domain, a central TPR-domain important for binding to other proteins (chaperones included) and a C-terminal domain involved in hydrophobic interactions. Both these SGTs are involved in the cellular PQC (protein quality control) system, as they interact with chaperones and have functions that aid stress recovery. However, there are differences between them, such as structural features and binding specificities, that could be better understood if other orthologous proteins were studied. Therefore, we produced and characterized a putative SGT protein, designated AaSGT, from the mosquito Aedes aegypti, which is a vector of several diseases, such as dengue and Zika. The protein was produced as a folded dimer which was stable up to 40 °C and was capable of binding to AaHsp90 and fully protecting a model protein, α-synuclein, from aggregation. The conformation of AaSGT was investigated by biophysical tools and small angle X-ray scattering, which showed that the protein had an elongated conformation and that its C-terminal domain was mainly disordered. The results with a C-terminal deletion mutant supported these observations. Altogether, these results are consistent with those from other functional SGT proteins and add to the understanding of the PQC system in Aedes aegypti, an important aim that may help to develop inhibitory strategies against this vector of neglected diseases.


Assuntos
Aedes/química , Proteínas de Insetos/química , Chaperonas Moleculares/química , Multimerização Proteica , Aedes/genética , Aedes/metabolismo , Animais , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Domínios Proteicos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
9.
ACS Appl Mater Interfaces ; 13(21): 24385-24400, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34006089

RESUMO

Self-assembly of thermally responsive polypeptides into unique nanostructures offers intriguing attributes including dynamic physical dimensions, biocompatibility, and biodegradability for the smart bio-nanomaterials. As elastin-based polypeptide (EBP) fusion proteins with lower critical solution temperature (LCST) are studied as drug delivery systems, EBP block copolypeptides with the resilin-based polypeptide (RBP) displaying an upper critical solution temperature (UCST) have been of great interest. In this study, we report thermally triggered, dynamic self-assembly of EBP- and RBP-based diblock copolypeptides into switched nanostructures with reversibility under physiological conditions. Molecular DNA clones encoding for the EBP-RBP diblocks at different block length ratios were biosynthesized via recursive directional ligation and overexpressed, followed by nonchromatographic purification by inverse transition cycling. Genetically engineered diblock copolypeptides composed of the EBP with an LCST and the RBP with a UCST showed converse phase transition behaviors with both a distinct LCST and a distinct UCST (LCST < UCST). As temperature increased, three phases of these EBP-RBP diblocks were observed: (1) self-assembled micelles or vesicles below both LCST and UCST, (2) whole aggregates above LCST and below UCST, and (3) reversed micelles above both LCST and UCST. In conclusion, these stimuli-triggered, dynamic protein-based nanostructures are promising for advanced drug delivery systems, regenerative medicine, and biomedical nanotechnology.


Assuntos
Elastina/química , Proteínas de Insetos/química , Peptídeos/química , Sequência de Aminoácidos , Transição de Fase
10.
Food Funct ; 12(9): 4132-4141, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33978000

RESUMO

Anthocyanin (cyanidin-3-O-glucose) is a natural water-soluble pigment with a robust antioxidant capacity. However, its poor stability and bioavailability limits its application as a functional food ingredient. This study explored the ability of the silkworm pupa protein-glucose (Spp-Glu) conjugate, developed under wet-heating conditions, to improve the thermal stability and antioxidant activity of cyanidin-3-O-glucose (C3G) at pH 3.0 and 6.8. The characterization experiments suggested that C3G complexed with the Spp-Glu conjugate could modify the protein's microenvironment and cause unfolding of the protein's secondary structures under varied pH conditions. Spectroscopic techniques further revealed the formation of complexes via hydrophobic interactions and static quenching processes when C3G was bound to Spp or Spp-Glu. The formation of these complexes effectively attenuated C3G degradation, thereby enhancing its stability under heat treatment over a range of pH values, and the experiments measuring antioxidant activity suggested that the Spp-Glu conjugate formed does not affect the efficacy of C3G after complexation. Therefore, our study suggests that Spp-Glu has the potential to effectively protect and deliver anthocyanins during industrial application for functional food formulation.


Assuntos
Antocianinas/química , Antocianinas/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bombyx/química , Glucose/química , Proteínas de Insetos/química , Animais , Estabilidade de Medicamentos , Alimento Funcional , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Estresse Oxidativo , Estrutura Secundária de Proteína , Pupa/química
11.
Ecotoxicol Environ Saf ; 220: 112334, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34020284

RESUMO

Artificial light at night (ALAN) is a widespread environmental pollutant and stressor. Many nocturnal insects have been shown to experience ALAN stress. However, few studies have been conducted to uncover the mechanism by which nocturnal insects respond to ALAN stress. Previous studies suggest that lysine succinylation (Ksuc) is a potential mechanism that coordinates energy metabolism and antioxidant activity under stressful conditions. Mythimna separata (Walker) (M. separata) is a nocturnal insect that has been stressed by ALAN. In this study, we quantified the relative proteomic Ksuc levels in ALAN-stressed M. separata. Of the 466 identified Ksuc-modified proteins, 103 were hypersuccinylated/desuccinylated in ALAN-stressed moths. The hypersuccinylated/desuccinylated proteins were shown to be involved in various biological processes. In particular, they were enriched in metabolic processes, reactive oxygen species (ROS) homeostasis and the neuromuscular system. Furthermore, we demonstrated that Ksuc might affect moth locomotion by intervening with and coordinating these systems under ALAN stress. These findings suggest that Ksuc plays a vital role in the moth response to ALAN stress and moth locomotion behavior and provide a new perspective on the impact of ALAN on nocturnal insect populations and species communities.


Assuntos
Proteínas de Insetos/química , Luz , Iluminação , Lisina/química , Mariposas/fisiologia , Fototaxia , Proteoma/química , Animais , Antioxidantes/metabolismo , Metabolismo Energético , Estresse Fisiológico
12.
Commun Biol ; 4(1): 491, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888855

RESUMO

Scales are symbolic characteristic of Lepidoptera; however, nothing is known about the contribution of cuticular proteins (CPs) to the complex patterning of lepidopteran scales. This is because scales are resistant to solubilization, thus hindering molecular studies. Here we succeeded in dissolving developing wing scales from Bombyx mori, allowing analysis of their protein composition. We identified a distinctive class of histidine rich (His-rich) CPs (6%-45%) from developing lepidopteran scales by LC-MS/MS. Functional studies using RNAi revealed CPs with different histidine content play distinct and critical roles in constructing the microstructure of the scale surface. Moreover, we successfully synthesized films in vitro by crosslinking a 45% His-rich CP (BmorCPR152) with laccase2 using N-acetyl- dopamine or N-ß-alanyl-dopamine as the substrate. This molecular study of scales provides fundamental information about how such a fine microstructure is constructed and insights into the potential application of CPs as new biomaterials.


Assuntos
Escamas de Animais/química , Bombyx/química , Proteínas de Insetos/química , Proteínas/química , Asas de Animais/química , Escamas de Animais/efeitos dos fármacos , Animais , Bombyx/efeitos dos fármacos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Asas de Animais/efeitos dos fármacos
13.
Molecules ; 26(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805599

RESUMO

Marine feed ingredients derived from cephalopods (e.g., squid) and crustaceans (e.g., krill) are commercially used to improve the palatability of shrimp diets. Increase in global demand for shrimps has resulted in overfishing of these marine organisms and is a matter of concern. Insect protein hydrolysate could be a sustainable alternative for the possible replacement of these marine feed ingredients. During this study, four formulations: diet A (control: not containing any palatability enhancer), diet B (containing squid meal and krill oil), diet C (containing 1% insect protein hydrolysate), and diet D (containing 2% insect protein hydrolysate) were tested for (1) time required by first subject to begin feeding (time to strike) and (2) palatability in Litopenaeus vannamei. Additionally, the chemical composition of all four diet formulations was also analyzed. Results indicate that all diets had similar crude composition. The major essential amino acids in all diets were leucine and lysine, whereas eicosapentaenoic acid was the major omega-3 fatty acid in all diets. There were no significant differences between the mean time to strike for all the tested formulations. Palatability of tested formulations was found in the following order: diet D > diet C > diet B = diet A (p < 0.05), indicating that addition of squid meal and krill oil has no effect on palatability in comparison to control, whereas inclusion of insect protein hydrolysates significantly improves the palatability of formulations. Palatability enhancement potential of insect protein hydrolysate could be attributed to the high free amino acid content and water solubility in comparison to squid meal.


Assuntos
Ração Animal/análise , Dípteros/química , Proteínas de Insetos/química , Penaeidae/fisiologia , Aminoácidos Essenciais/análise , Animais , Aquicultura/métodos , Proteínas de Artrópodes/química , Conservação dos Recursos Naturais , Decapodiformes/química , Dieta , Proteínas na Dieta/química , Euphausiacea/química , Preferências Alimentares , Humanos , Larva/química , Penaeidae/crescimento & desenvolvimento , Hidrolisados de Proteína/química , Solubilidade
14.
Artigo em Inglês | MEDLINE | ID: mdl-33838314

RESUMO

Bee venom is a mixture of bioactive components that include proteases and protease inhibitors. A metalloprotease inhibitor has been predicted to be a bumblebee-specific toxin in the venom proteome of Bombus terrestris; however, the identification and functional roles of bee venom metalloprotease inhibitors have not been previously determined. In this study, we identified a bumblebee (B. ignitus) venom metalloprotease inhibitor (BiVMPI) that exhibits anti-fibrinolytic activity. BiVMPI contains a trypsin inhibitor-like cysteine-rich domain that exhibits similarity to inducible metalloprotease inhibitor. Using an anti-BiVMPI antibody raised against a recombinant BiVMPI protein produced in baculovirus-infected insect cells, the presence of BiVMPI in the venom gland and secreted venom of B. ignitus worker bees was confirmed. The recombinant BiVMPI protein demonstrated inhibitory activity against a metalloprotease, trypsin, chymotrypsin, protease K, and plasmin, but not subtilisin A, elastase, or thrombin. Additionally, the recombinant BiVMPI bound to plasmin and inhibited the plasmin-mediated degradation of fibrin, demonstrating an anti-fibrinolytic role for BiVMPI as a bee venom metalloprotease inhibitor. Our results provide the first evidence for the identification and anti-fibrinolytic activity of a metalloprotease inhibitor from bee venom.


Assuntos
Venenos de Abelha/química , Fibrinogênio/química , Proteínas de Insetos/química , Inibidores de Metaloproteinases de Matriz/química , Proteínas Recombinantes/química , Animais , Abelhas , Fibrinolisina/química , Humanos
15.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33688047

RESUMO

The mosquito protein AEG12 is up-regulated in response to blood meals and flavivirus infection though its function remained elusive. Here, we determine the three-dimensional structure of AEG12 and describe the binding specificity of acyl-chain ligands within its large central hydrophobic cavity. We show that AEG12 displays hemolytic and cytolytic activity by selectively delivering unsaturated fatty acid cargoes into phosphatidylcholine-rich lipid bilayers. This property of AEG12 also enables it to inhibit replication of enveloped viruses such as Dengue and Zika viruses at low micromolar concentrations. Weaker inhibition was observed against more distantly related coronaviruses and lentivirus, while no inhibition was observed against the nonenveloped virus adeno-associated virus. Together, our results uncover the mechanistic understanding of AEG12 function and provide the necessary implications for its use as a broad-spectrum therapeutic against cellular and viral targets.


Assuntos
Antivirais/metabolismo , Hemolíticos/metabolismo , Proteínas de Insetos/metabolismo , Lipídeos , Animais , Antivirais/química , Antivirais/farmacologia , Linhagem Celular , Membrana Celular/metabolismo , Culicidae , Eritrócitos/efeitos dos fármacos , Ácidos Graxos Insaturados/metabolismo , Hemolíticos/química , Hemolíticos/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Insetos/química , Proteínas de Insetos/farmacologia , Ligantes , Lipídeos/química , Ligação Proteica , Estrutura Terciária de Proteína , Envelope Viral/metabolismo , Vírus/efeitos dos fármacos , Vírus/metabolismo
16.
Arch Insect Biochem Physiol ; 106(4): e21770, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33660279

RESUMO

MGST2 is a member of the MAPEG superfamily, which participates in LTC4 synthesis and plays important roles in the regulation of the oxidative stress pathway and some diseases. Here, we isolated a previously uncharacterized gene in Apis cerana cerana named AccMGST2 by reverse transcription-polymerase chain reaction. The biological characteristics of AccMGST2 were analyzed by bioinformatics. The amino acid sequence similarity between AccMGST2 and AmMGST2 of Apis mellifera reached 96.08%. The expression characteristics of AccMGST2 were explored in several tissues. The quantitative real-time polymerase chain reaction results showed that the AccMGST2 gene was highly expressed in the head and muscle and that AccMGST2 expression responded to oxidative stress caused by different abiotic stresses. AccMGST2 was silenced using RNA interference, which decreased the expression levels of some MAPK and antioxidant genes. Therefore, we conclude that AccMGST2 is involved in the regulation of oxidative stress in A. cerana cerana.


Assuntos
Abelhas/genética , Glutationa Transferase , Sequência de Aminoácidos , Animais , Antioxidantes/metabolismo , Genes de Insetos , Glutationa Transferase/química , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Estresse Oxidativo/genética , Filogenia
17.
Arch Insect Biochem Physiol ; 106(4): e21772, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33719088

RESUMO

The ß-adrenergic-like octopamine receptor (OA2B2), which binds the biogenic amine octopamine, belongs to the class of G-protein coupled receptors and significantly regulates many physiological and behavioral processes in insects. In this study, the putative open reading frame sequence of the MsOA2B2 gene in Mythimna separata was cloned, the full-length complementary DNA was 1191 bp and it encoded a 396-amino acid protein (GenBank accession number MN822800). Orthologous sequence alignment, phylogenetic tree analysis, and protein sequence analysis all showed that the cloned receptor belongs to the OA2B2 protein family. Real-time quantitative polymerase chain reaction of spatial and temporal expression analysis revealed that the MsOAB2 gene was expressed in all developmental stages of M. separata and was most abundant in egg stages and second and fourth instars compared with other developmental stages, while the expression level during the pupal stage was much lower than that at the other stages. Further analysis with sixth instar M. separata larvae showed that the MsOA2B2 gene was expressed 1.81 times higher in the head than in integument and gut tissues. Dietary ingestion of dsMsOA2B2 significantly reduced the messenger RNA level of MsOA2B2 and decreased mortality following amitraz treatment. This study provides both a pharmacological characterization and the gene expression patterns of OA2B2 in M. separata, facilitating further research for insecticides using MsOA2B2 as a target.


Assuntos
Mariposas/genética , Receptores de Amina Biogênica , Animais , Expressão Gênica/efeitos dos fármacos , Genes de Insetos , Controle de Insetos , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Inseticidas/farmacologia , Larva/genética , Larva/metabolismo , Mariposas/metabolismo , Filogenia , Pupa/genética , Pupa/metabolismo , Receptores Adrenérgicos beta/química , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores Adrenérgicos beta/genética , Receptores Adrenérgicos beta/metabolismo , Receptores de Amina Biogênica/química , Receptores de Amina Biogênica/efeitos dos fármacos , Receptores de Amina Biogênica/genética , Receptores de Amina Biogênica/metabolismo , Toluidinas/farmacologia
18.
Arch Insect Biochem Physiol ; 106(3): e21771, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33644898

RESUMO

Antimicrobial proteins (AMPs) are small, cationic proteins that exhibit activity against bacteria, viruses, parasites, fungi as well as boost host-specific innate immune responses. Insects produce these AMPs in the fat body and hemocytes, and release them into the hemolymph upon microbial infection. Hemolymph was collected from the bacterially immunized fifth instar larvae of tasar silkworm, Antheraea mylitta, and an AMP was purified by organic solvent extraction followed by size exclusion and reverse-phase high-pressure liquid chromatography. The purity of AMP was confirmed by thin-layer chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The molecular mass was determined by matrix-assisted laser desorption ionization-time of flight mass spectrometry as 14 kDa, and hence designated as AmAMP14. Peptide mass fingerprinting of trypsin-digested AmAMP14 followed by de novo sequencing of one peptide fragment by tandem mass spectrometry analysis revealed the amino acid sequences as CTSPKQCLPPCK. No homology was found in the database search and indicates it as a novel AMP. The minimum inhibitory concentration of the purified AmAMP14 was determined against Escherichia coli, Staphylococcus aureus, and Candida albicans as 30, 60, and 30 µg/ml, respectively. Electron microscopic examination of the AmAMP14-treated cells revealed membrane damage and release of cytoplasmic contents. All these results suggest the production of a novel 14 kDa AMP in the hemolymph of A. mylitta to provide defense against microbial infection.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Hemolinfa/metabolismo , Proteínas de Insetos/isolamento & purificação , Mariposas/metabolismo , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/farmacologia , Candida albicans/efeitos dos fármacos , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Escherichia coli/efeitos dos fármacos , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Proteínas de Insetos/farmacologia , Larva/metabolismo , Extração Líquido-Líquido/métodos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos
19.
Photochem Photobiol Sci ; 20(1): 113-122, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33721241

RESUMO

Beetle luciferases catalyze the bioluminescent oxidation of D-luciferin, producing bioluminescence colors ranging from green to red, using two catalytic steps: adenylation of D-luciferin to produce D-luciferyl-adenylate and PPi, and oxidation of D-luciferyl-adenylate, yielding AMP, CO2, and excited oxyluciferin, the emitter. Luciferases and CoA-ligases display a similar fold, with a large N-terminal domain, and a small C-terminal domain which undergoes rotation, closing the active site and promoting both adenylation and oxidative reactions. The effect of C-terminal domain deletion was already investigated for Photinus pyralis firefly luciferase, resulting in a red-emitting mutant with severely impacted luminescence activity. However, the contribution of C-terminal in the bioluminescence activities and colors of other beetle luciferases and related ancestral luciferases were not investigated yet. Here we compared the effects of the C-terminal domain deletion on green-emitting luciferases of Pyrearinus termitilluminans (Pte) click beetle and Phrixothrix vivianii railroadworm, and on the red-emitting luciferase of Phrixothrix hirtus railroadworm and luciferase-like enzyme of Zophobas morio. In all cases, the domain deletion severely impacted the overall bioluminescence activities and, slightly less, the oxidative activities, and usually red-shifted the bioluminescence colors. The results support the involvement of the C-terminal in shielding the active site from the solvent during the light emitting step. However, in Pte luciferase, the deletion caused only a 10 nm red-shift, indicating a distinctive active site which remains more shielded, independently of the C'-terminal. Altogether, the results confirm the main contribution of the C-terminal for the catalysis of the adenylation reaction and for active site shielding during the light emitting step.


Assuntos
Proteínas de Insetos/metabolismo , Luciferases/metabolismo , Sequência de Aminoácidos , Animais , Benzotiazóis/química , Benzotiazóis/metabolismo , Sítios de Ligação , Besouros/enzimologia , Proteínas de Insetos/química , Proteínas de Insetos/genética , Cinética , Luciferases/química , Luciferases/genética , Luciferases de Vaga-Lume/química , Luciferases de Vaga-Lume/genética , Luciferases de Vaga-Lume/metabolismo , Medições Luminescentes , Simulação de Acoplamento Molecular , Mutagênese , Domínios Proteicos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
20.
PLoS One ; 16(3): e0241881, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33764987

RESUMO

Melanaphis sacchari (Zehntner, 1897) and Melanaphis sorghi (Theobald, 1904) are major worldwide crop pests causing direct feeding damage on sorghum and transmitting viruses to sugarcane. It is common in the scientific literature to consider these two species as synonyms, referred to as the 'sugarcane aphid', although no formal study has validated this synonymy. In this study, based on the comparison of samples collected from their whole distribution area, we use both morphometric and molecular data to better characterize the discrimination between M. sacchari and M. sorghi. An unsupervised multivariate analysis of morphometric data clearly confirmed the separation of the two species. The best discriminating characters separating these species were length of the antenna processus terminalis relative to length of hind tibia, siphunculus or cauda. However, those criteria sometimes do not allow an unambiguous identification. Bayesian clustering based on microsatellite data delimited two clusters, which corresponded to the morphological species separation. The DNA sequencing of three nuclear and three mitochondrial regions revealed slight divergence between species. In particular, the COI barcode region proved to be uninformative for species separation because one haplotype is shared by both species. In contrast, one SNP located on the nuclear EF1-α gene was diagnostic for species separation. Based on morphological and molecular evidence, the invasive genotype damaging to sorghum in the US, Mexico and the Caribbean since 2013 is found to be M. sorghi.


Assuntos
Afídeos/genética , Saccharum/parasitologia , Sorghum/parasitologia , Animais , Afídeos/fisiologia , Antenas de Artrópodes/fisiologia , Teorema de Bayes , Análise por Conglomerados , DNA/química , DNA/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Genótipo , Haplótipos , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Repetições de Microssatélites/genética , Mitocôndrias/genética , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...