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1.
Sci Rep ; 12(1): 7597, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534525

RESUMO

To apply the sterilisation effect of low-temperature plasma to the oral cavity, the issue of ozone from plasma must be addressed. In this study, a new technology for generating cold plasma with almost no ozone is developed and is named Nozone (no-ozone) Cold Plasma (NCP) technology. The antimicrobial efficacy of the NCP against four oral pathogens is tested, and its specific mechanism is elucidated. The treatment of NCP on oral pathogenic microbes on a solid medium generated a growth inhibition zone. When NCP is applied to oral pathogens in a liquid medium, the growth of microbes decreased by more than 105 colony forming units, and the bactericidal effect of NCP remained after the installation of dental tips. The bactericidal effect of NCP in the liquid medium is due to the increase in hydrogen peroxide levels in the medium. However, the bactericidal effect of NCP in the solid medium depends on the charged elements of the NCP. Furthermore, the surface bactericidal efficiency of the dental-tip-installed NCP is proportional to the pore size of the tips and inversely proportional to the length of the tips. Overall, we expect this NCP device to be widely used in dentistry in the near future.


Assuntos
Anti-Infecciosos , Ozônio , Gases em Plasma , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Peróxido de Hidrogênio/farmacologia , Ozônio/farmacologia , Gases em Plasma/farmacologia
3.
Anticancer Res ; 42(1): 555-563, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34969765

RESUMO

BACKGROUND: Epstein-Barr virus (EBV)-associated gastric cancer has been identified as a cancer subtype with definitive clinical and molecular characteristics. Although olaparib, a poly ADP ribose polymerase (PARP) inhibitor, is considered a potential effective agent for gastric cancer, the effect and underlying mechanism of olaparib on gastric cancer depending on EBV infection is not fully understood. MATERIALS AND METHODS: EBV-positive SNU719 and EBV-negative SNU638 gastric cancer cell lines were used to identify the effects of olaparib using the trypan blue exclusion method and annexin V staining assay. To observe the underlying cellular signaling mechanisms of olaparib-induced cell death, Epstein-Barr virus nuclear antigen 1 (EBNA1) and signaling related molecule expression were assessed using transfection, silencing of specific genes using small interfering RNA (siRNA), western blotting and signaling inhibition assay. RESULTS: Olaparib decreased the cell viability of EBV-positive SNU719 gastric cancer cells through caspase-3-dependent apoptosis in a dose dependent manner, whereas EBV-negative SNU638 gastric cancer cells showed drug resistance to olaparib. EBNA1 was expressed in SUN719 gastric cancer cells; however, ataxia telangiectasia and Rad3 related (ATR) and phosphorylated ATR kinase were expressed in SNU638 gastric cancer cells. EBNA1 transfection decreased ATR phosphorylation through p38 mitogen-activated protein kinase (MAPK) phosphorylation in SUN638 gastric cancer cells, and silencing of ATR kinase increased the susceptibility of these cells to olaparib treatment. Moreover, VE-821, an ATR kinase specific inhibitor, also increased the sensitivity of SNU638 cells to olaparib. In contrast, SB203580, a p38 MAPK inhibitor, inhibited this increase in sensitivity to olaparib by EBNA1 transfection. CONCLUSION: Olaparib treatment led to different cellular responses depending on EBV infection in gastric cancer cell lines. These results provide new insights into the mechanism of olaparib-induced apoptosis in gastric cancer cells and suggest that EBV infection should be considered when developing new potential therapeutic agents for gastric cancer.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Antígenos Nucleares do Vírus Epstein-Barr/genética , Ftalazinas/farmacologia , Piperazinas/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Antígenos Nucleares do Vírus Epstein-Barr/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 4/patogenicidade , Humanos , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/virologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
4.
J Cell Mol Med ; 25(17): 8300-8311, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34318593

RESUMO

Dasatinib is an inhibitor of Src that has anti-tumour effects on many haematological and solid cancers. However, the anti-tumour effects of dasatinib on human oral cancers remain unclear. In this study, we investigated the effects of dasatinib on different types of human oral cancer cells: the non-tumorigenic YD-8 and YD-38 and the tumorigenic YD-10B and HSC-3 cells. Strikingly, dasatinib at 10 µM strongly suppressed the growth and induced apoptosis of YD-38 cells and inhibited the phosphorylation of Src, EGFR, STAT-3, STAT-5, PKB and ERK-1/2. In contrast, knockdown of Src blocked the phosphorylation of EGFR, STAT-5, PKB and ERK-1/2, but not STAT-3, in YD-38 cells. Dasatinib induced activation of the intrinsic caspase pathway, which was inhibited by z-VAD-fmk, a pan-caspase inhibitor. Dasatinib also decreased Mcl-1 expression and S6 phosphorylation while increased GRP78 expression and eIF-2α phosphorylation in YD-38 cells. In addition, to its direct effects on YD-38 cells, dasatinib also exhibited anti-angiogenic properties. Dasatinib-treated YD-38 or HUVEC showed reduced HIF-1α expression and stability. Dasatinib alone or conditioned media from dasatinib-treated YD-38 cells inhibited HUVEC tube formation on Matrigel without affecting HUVEC viability. Importantly, dasatinib's anti-growth, anti-angiogenic and pro-apoptotic effects were additionally seen in tumorigenic HSC-3 cells. Together, these results demonstrate that dasatinib has strong anti-growth, anti-angiogenic and pro-apoptotic effects on human oral cancer cells, which are mediated through the regulation of multiple targets, including Src, EGFR, STAT-3, STAT-5, PKB, ERK-1/2, S6, eIF-2α, GRP78, caspase-9/3, Mcl-1 and HIF-1α.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Dasatinibe/farmacologia , Neoplasias Bucais/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Linhagem Celular Tumoral , Humanos
5.
J Cell Mol Med ; 22(12): 5833-5846, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30246484

RESUMO

Meridianin C is a marine natural product known for its anti-cancer activity. At present, the anti-tumour effects of meridianin C on oral squamous cell carcinoma are unknown. Here, we investigated the effect of meridianin C on the proliferation of four different human tongue cancer cells, YD-8, YD-10B, YD-38 and HSC-3. Among the cells tested, meridianin C most strongly reduced the growth of YD-10B cells; the most aggressive and tumorigenic of the cell lines tested. Strikingly, meridianin C induced a significant accumulation of macropinosomes in the YD-10B cells; confirmed by the microscopic and TEM analysis as well as the entry of FITC-dextran, which was sensitive to the macropinocytosis inhibitor amiloride. SEM data also revealed abundant long and thin membrane extensions that resemble lamellipodia on the surface of YD-10B cells treated with meridianin C, pointing out that meridianin C-induced macropinosomes was the result of macropinocytosis. In addition, meridianin C reduced cellular levels of Dickkopf-related protein-3 (DKK-3), a known negative regulator of macropinocytosis. A role for DKK-3 in regulating macropinocytosis in the YD-10B cells was confirmed by siRNA knockdown of endogenous DKK-3, which led to a partial accumulation of vacuoles and a reduction in cell proliferation, and by exogenous DKK-3 overexpression, which resulted in a considerable inhibition of the meridianin C-induced vacuole formation and decrease in cell survival. In summary, this is the first study reporting meridianin C has novel anti-proliferative effects via macropinocytosis in the highly tumorigenic YD-10B cell line and the effects are mediated in part through down-regulation of DKK-3.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Alcaloides Indólicos/farmacologia , Indóis/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pinocitose/efeitos dos fármacos , Pirimidinas/farmacologia , Neoplasias da Língua/metabolismo , Neoplasias da Língua/patologia , Proteínas Adaptadoras de Transdução de Sinal , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimiocinas , Humanos , Alcaloides Indólicos/química , Indóis/química , Pirimidinas/química , Neoplasias da Língua/ultraestrutura , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo
6.
Lung Cancer ; 106: 115-124, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28285685

RESUMO

OBJECTIVES: Erlotinib, a tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR), has been shown to have a dramatic effect in non-small cell lung cancer (NSCLC) patients with EGFR mutation. However, the presence of primary resistance or acquired resistance to EGFR-TKI is the most common reason for switching to other anti-cancer agents. Even though there are newer agents that have activity in the presence of the T790M mutation, identification of potential agents that could overcome resistance to EGFR-TKI is still needed for the treatment of NSCLC patients. MATERIALS AND METHODS: In this study, we used erlotinib-resistant NSCLC cell lines to investigate the effects of combination treatment with erlotinib and ampelopsin. After treatment with either single or combination, cell viability and cell death were determined with WST-1 assay, trypan blue exclusion method, colony forming assay, annexin-V staining assay and western blot assay. The content of ROS was evaluated by FACS analysis using H2DCF-staining method. To determine the effect of Nox2 and Bim on the combined treatment with erlotinib and ampelopsin-induced cell death, we transfected with Nox2 or Bim specific siRNA and performed with western blot assay for evaluation of its expression. RESULTS: Combined treatment with erlotinib and ampelopsin at non-cytotoxic concentrations significantly induced caspase-dependent cell death in erlotinib-resistant NSCLC cells. Furthermore, cell death resulted in the accumulation of reactive oxygen species (ROS) through upregulation of nicotinamide adenine dinucleotide phosphate oxidase 2 (Nox2) expression, a direct source of ROS. The expression level of Bim increased with combination treatment, but not with either treatment alone. CONCLUSION: Here in this study, we demonstrate that the combination of erlotinib and ampelopsin induces cell death via the Nox2-ROS-Bim pathway, and ampelopsin could be used as a novel anti-cancer agent combined with EGFR-TKI to overcome resistance to erlotinib in EGFR-mutant NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Terapia Combinada/métodos , Cloridrato de Erlotinib/farmacologia , Flavonoides/farmacologia , NADPH Oxidase 2/genética , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral/efeitos dos fármacos , Ensaios Clínicos como Assunto , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Cloridrato de Erlotinib/metabolismo , Flavonoides/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo
7.
DNA Seq ; 18(2): 160-4, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17364828

RESUMO

A full-length cDNA clone with high homology (62% mature peptide sequence identity) to an Acalolepta luxuriosa antibacterial gene, possessing a conserved cysteine-stabilized alphabeta motif, was cloned by screening an Apriona germari cDNA library. This gene (AgCRP) had a total length of 360 bp with an open reading frame of 207 bp, and encoded a predicted peptide of 69 amino acid residues. The mature AgCRP peptide was 27 amino acid residues long and had a cysteine-stabilized alphabeta motif of C...CXXXC...C...CXC consensus sequence, similar to insect defensins. Northern blot analysis revealed that the AgCRP exhibited fat body-specific expression and was up-regulated by wounding, bacterial or fungal challenge.


Assuntos
Antibacterianos/química , Besouros/genética , DNA Complementar/genética , Defensinas/genética , Genes de Insetos , Proteínas de Insetos/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Defensinas/metabolismo , Proteínas de Insetos/genética , Dados de Sequência Molecular , Peptídeos/genética , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
8.
J Med Food ; 9(2): 214-22, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16822207

RESUMO

We investigated the effects of the fruiting bodies of cultivated Paecilomyces tenuipes grown on egg yolk (PTE) on lipid and antioxidant metabolisms. Forty 8-week-old male Sprague-Dawley rats were fed a high fat/high cholesterol diet (control) or a high fat/high cholesterol diet with 1%, 3%, or 5% PTE for 5 weeks. PTE was found to significantly lower plasma total lipid, total cholesterol, low-density lipoprotein cholesterol, and the atherogenic index, compared with the control. Hepatic total lipid and total cholesterol were also significantly lower than in the control group. The hypolipidemic activity of PTE was increased with increasing concentrations, and plasma lipid peroxidation was significantly lower in the 3% and 5% PTE groups than in the control or 1% PTE group. Plasma total radical trapping antioxidant potential, erythrocytic antioxidant enzyme, and leukocytic DNA damage were not significantly different among the groups. Our results indicate that P. tenuipes cultivated on egg yolk can improve lipid profiles and lipid peroxidation in rats fed a high fat/high cholesterol diet.


Assuntos
Gorduras na Dieta/administração & dosagem , Gema de Ovo , Hipolipemiantes/administração & dosagem , Lipídeos/sangue , Paecilomyces/química , Paecilomyces/crescimento & desenvolvimento , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Catalase/sangue , Colesterol/sangue , Colesterol na Dieta/administração & dosagem , LDL-Colesterol/sangue , Eritrócitos/enzimologia , Carpóforos/química , Glutationa Peroxidase/sangue , Hipolipemiantes/isolamento & purificação , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos/análise , Fígado/química , Masculino , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/sangue
9.
Cancer Res Treat ; 38(2): 118-20, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19771270

RESUMO

Solid pseudopapillary tumor of the pancreas (SPTP) is a rare primary pancreatic tumor of an unknown etiology that is usually diagnosed in adolescent girls and young women. Most SPTPs are considered to be benign and only rarely metastasize. We report here on a 27-year old woman with recurrent SPTP with involvement of both the spleen and left kidney at the time of the initial diagnosis, and with aggressive behavior. In July 1995, she was admitted with abdominal discomfort and mass. She underwent exploratory laparotomy with distal pancreatectomy, left nephrectomy and splenectomy, and was diagnosed with SPTP with invasion to both the spleen and left kidney. In June 2001, she again presented with abdominal pain and was diagnosed as having recurrence of the tumor. She underwent mass excision and omentectomy. Then she was lost to follow-up. In November 2005, she presented once again with an abdominal mass and was diagnosed with recurred SPTP, which formed a huge intraperitoneal mass with peritoneal seeding and the tumor showed multiple metastases in the liver. She is currently being treated conservatively.

10.
DNA Seq ; 16(5): 397-401, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16323268

RESUMO

In our research to identify gene involved in the cuticle protein, we cloned a novel cuticle protein gene, ApCP13, from the Chinese oak silkmoth, Antheraea pernyi, larvae cDNA library. The ApCP13 gene encodes a 120 amino acid polypeptide with a predicted molecular mass of 13 kDa and a pI of 4.01, and is intron-less gene. The ApCP13 contained a type-specific consensus sequence identifiable in other insect cuticle proteins and the deduced amino acid sequence of the ApCP13 cDNA is most homologous to another wild silkmoth, A. yamamai CP12 (86% protein sequence identity), followed by Bombyx mori LCP18 (35% protein sequence identity). Northern blot analysis revealed that the ApCP13 showed the epidermis-specific expression. This is the first report of cuticle protein gene in the wild silkmoth, A. pernyi.


Assuntos
Bombyx/genética , Proteínas de Insetos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Biblioteca Gênica , Proteínas de Insetos/isolamento & purificação , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
11.
Biotechnol Lett ; 27(19): 1499-504, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16231223

RESUMO

A cuticle protein gene, AyCP12, from the Japanese oak silkmoth, Antheraea yamamai, was isolated and characterized. The gene spans 1107 bp and consists of one intron and two exons coding for a 112 amino acid polypeptide with a predicted molecular mass of 12,163 Da and a pI of 4.4. The AyCP12 protein contained a type-specific consensus sequence identifiable in other insect cuticle proteins and the deduced amino acid sequence of the AyCP12 cDNA is most homologous to another silkmoth, A. pernyi, cuticle protein ApCP13 (82% protein sequence identity). Northern blot analysis revealed that AyCP12 showed the epidermis-specific expression.


Assuntos
Bombyx/genética , DNA Complementar/química , Proteínas de Insetos/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , Sequência Conservada , DNA Complementar/isolamento & purificação , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Biblioteca Gênica , Proteínas de Insetos/metabolismo , Larva , Dados de Sequência Molecular , RNA Mensageiro/isolamento & purificação , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
12.
J Korean Med Sci ; 20(3): 409-16, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15953861

RESUMO

Androgens remain a common treatment for certain type of anemia, based upon its myelostimulating effects; however, it has not been established whether androgens affect apoptosis of hematopoietic progenitor cells (HPCs). We investigated the effects of the androgens, such as testosterone, 5beta-dihydrotestosterone (5-DHT), and oxymetholone, on apoptosis of normal hematopoietic progenitor cells in vitro. Androgens did not rescue normal bone marrow (BM) CD34+ cells and colony-forming cells (CFCs), other than mature erythroid CFCs, from apoptosis induced by serum- and growth factor deprivation. Oxymetholone did not affect growth factor-mediated survival of normal CD34+ cells or its inhibition by interferon-gamma (IFN-gamma). In a standard methylcellulose clonogenic assay, low concentrations of oxymetholone and 5-DHT stimulated the clonal growth of colony-forming unit (CFU)-erythroid, but did not affect growth of CFU-granulocyte/macrophage or burst-forming unit-erythroid. Oxymetholone and 5-DHT stimulated the production of stem cell factor in normal bone marrow stromal cells (BMSCs) via transcriptional regulation. In agreement with this, oxymetholone-treated BMSCs better supported the survival of HPCs. These data indicate that survival-enhancing or growth-stimulatory effects of androgens on hematopoietic progenitor cells are minimal and mostly restricted to mature erythroid progenitors, and its myelostimulating effects could be attributed, at least in part, to the stimulation of production of hematopoietic growth factors in BMSCs.


Assuntos
Androgênios/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Antígenos CD34/análise , Apoptose/efeitos dos fármacos , Northern Blotting , Western Blotting , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CXCL12 , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Ensaio de Unidades Formadoras de Colônias , Citocinas/genética , Citocinas/farmacologia , Di-Hidrotestosterona/farmacologia , Relação Dose-Resposta a Droga , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Oximetolona/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Testosterona/farmacologia , Fatores de Tempo
13.
Mycologia ; 97(1): 130-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16389964

RESUMO

We describe the molecular characterization of the Cu,Zn superoxide dismutase (SOD1) gene of Cordyceps militaris, which is one of the entomopathogenic fungi called a vegetable wasp and plant worm. The SOD1 gene of C. militaris spans 922 bp and consisted of three introns and four exons coding for 154 amino acid residues. The deduced amino acid sequence of the C. militaris SOD1 cDNA showed 88% identity to Claviceps purpurea SOD1, 82% to Neurospora crassa SOD1, and 75-64% to SOD1 sequences from other fungi. The C. militaris SOD1 possesses the typical metal binding ligands of six histidines and one aspartic acid common to fungal SOD1s. The cDNA encoding C. militaris SOD1 was expressed as a 17-kDa polypeptide in the baculovirus-infected insect Sf9 cells. The enzyme activity of the purified recombinant C. militaris SOD1 was approximately 568 U per mg(-1) . Southern blot analysis of the genomic DNA suggested the C. militaris SOD1 was a single gene. Northern and Western blot analysis and enzyme activity assays indicated SOD1 was expressed constitutively. This is the first report of an SOD1 gene from any entomopathogenic fungus.


Assuntos
Clonagem Molecular , Cordyceps/enzimologia , Superóxido Dismutase , Sequência de Aminoácidos , Animais , Baculoviridae/genética , Baculoviridae/metabolismo , Sequência de Bases , Células Cultivadas , Cobre/metabolismo , Cordyceps/genética , Cordyceps/patogenicidade , DNA Fúngico/análise , Dados de Sequência Molecular , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Spodoptera/microbiologia , Superóxido Dismutase/genética , Superóxido Dismutase/isolamento & purificação , Superóxido Dismutase/metabolismo , Zinco/metabolismo
14.
Insect Biochem Mol Biol ; 35(1): 73-84, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15607657

RESUMO

A thioredoxin peroxidase (TPx) that reduces H(2)O(2) was firstly characterized in the lepidopteran insect, silkworm Bombyx mori. The B. mori TPx (BmTPx) cDNA contains an open reading frame of 585 bp encoding 195 amino acid residues and possesses two cysteine residues that are characteristic of 2-Cys subgroup of peroxiredoxin family. The deduced amino acid sequence of the BmTPx cDNA showed 78% identity to Drosophila melanogaster (DmTPx-1), 73% to Aedes aegypti (AaTPx), and 54-48% to other insect 2-Cys TPx. The cDNA encoding BmTPx was expressed as a 25-kDa polypeptide in baculovirus-infected insect Sf9 cells. The purified recombinant BmTPx was shown to reduce H(2)O(2) in the presence of electrons donated by dithiothreitol and shown to be active in the presence of thioredoxin as electron donor. Northern blot analysis revealed the presence of BmTPx transcripts in all tissues examined. Western blot analysis showed the presence of the BmTPx in the fat body and midgut, but not in the hemolymph, suggesting the BmTPx is not secretable. When H(2)O(2) was injected into body cavity of B. mori larva, BmTPx mRNA expression was up-regulated in the fat body tissues. Interestingly, the expression levels of BmTPx enzyme in the fat body were particularly high when B. mori larva was exposed at low (4 degrees C) and high (37 degrees C) temperatures or baculovirus infection, suggesting that the BmTPx seems to play a protective role against oxidative stress caused by temperature stimuli and viral infection.


Assuntos
Bombyx/enzimologia , Bombyx/virologia , Peroxidases/biossíntese , Peroxidases/química , Temperatura , Sequência de Aminoácidos , Animais , Sequência de Bases , Bombyx/genética , Linhagem Celular , Indução Enzimática , Larva/enzimologia , Dados de Sequência Molecular , Nucleopoliedrovírus , Peroxidases/genética , Peroxirredoxinas , Proteínas Recombinantes/biossíntese , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
15.
Comp Biochem Physiol B Biochem Mol Biol ; 138(4): 423-33, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15325344

RESUMO

Insect secreted ferritins are composed of subunits, which resemble heavy and light chains of vertebrate cytosolic ferritins. We describe here the cloning, expression and characterization of cDNAs encoding the ferritin heavy-chain homologue (HCH) and light-chain homologue (LCH) from the mulberry longicorn beetle, Apriona germari (Coleoptera, Cerambycidae). The A. germari ferritin LCH and HCH cDNA sequences were comprised of 672 and 636 bp encoding 224 and 212 amino acid residues, respectively. The A. germari ferritin HCH subunit contained the conserved motifs for the ferroxidase center typical of vertebrate ferritin heavy chains and the iron-responsive element (IRE) sequence with a predicted stem-loop structure was present in the 5'-untranslated region (UTR) of ferritin HCH mRNA. However, the A. germari ferritin LCH subunit had no IRE at its 5'-UTR and ferroxidase center residues. Phylogenetic analysis confirmed the deduced protein sequences of A. germari ferritin HCH and LCH being divided into two types, G type (LCH) and S type (HCH). Southern blot analysis suggested the possible presence of each A. germari ferritin subunit gene as a single copy and Northern blot analysis confirmed a higher expression pattern in midgut than fat body. The cDNAs encoding the A. germari ferritin subunits were expressed as approximately 30 kDa (LCH) and 26 kDa (HCH) polypeptides in baculovirus-infected insect cells. Western blot analysis and iron staining assay confirmed that A. germari ferritin has a native molecular mass of approximately 680 kDa.


Assuntos
Ferritinas/química , Ferritinas/genética , Regiões 5' não Traduzidas , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Baculoviridae/genética , Sequência de Bases , Northern Blotting , Western Blotting , Clonagem Molecular , Besouros , DNA/metabolismo , DNA Complementar/metabolismo , Eletroforese em Gel de Poliacrilamida , Biblioteca Gênica , Vetores Genéticos , Hemolinfa/metabolismo , Insetos , Ferro/química , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Filogenia , Estrutura Terciária de Proteína , RNA/metabolismo , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Fatores de Tempo
16.
Arch Insect Biochem Physiol ; 56(2): 61-72, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15146541

RESUMO

An arylphorin-like hexameric storage protein, AgeHex2, cDNA was cloned from the mulberry longicorn beetle, Apriona germari (Coleoptera, Cerambycidae), larval cDNA library. The complete cDNA sequence of AgeHex2 is comprised of 2,088 bp encoding 696 amino acid residues. The AgeHex2 had four potential N-glycosylation sites. The AgeHex2 contained the highly conserved two larval storage protein signature motifs. The deduced protein sequence of AgeHex2 showed high homology with A. germari hexamerin1 (51% amino acid identity), Tenebrio molitor hexamerin2 (49% amino acid identity), T. molitor early-staged encapsulation inducing protein (43% amino acid identity), and Leptinotarsa decemlineata diapause protein1 (43% amino acid identity). Phylogenetic analysis further confirmed the AgeHex2 is more closely related to coleopteran hexamerins than to the other insect storage proteins. Northern blot analysis confirmed that the AgeHex2 showed fat body-specific expression. The cDNA encoding AgeHex2 was expressed as a 75-kDa protein in the baculovirus-infected insect cells. Furthermore, N-glycosylation of the recombinant AgeHex2 was revealed by tunicamycin to the recombinant virus-infected Sf9 cells, demonstrating that the AgeHex2 is N-glycosylated. Western blot analysis using the polyclonal antiserum against recombinant AgeHex2 indicated that the AgeHex2 corresponds to a 75-kDa storage protein present in the A. germari larval hemolymph.


Assuntos
Besouros/genética , Glicoproteínas/biossíntese , Glicoproteínas/genética , Proteínas de Insetos/biossíntese , Proteínas de Insetos/genética , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Baculoviridae/genética , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Besouros/metabolismo , DNA Complementar/genética , DNA Complementar/metabolismo , Glicoproteínas/química , Glicosilação , Proteínas de Insetos/química , Larva/genética , Larva/metabolismo , Dados de Sequência Molecular , Filogenia , Estrutura Quaternária de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Alinhamento de Sequência , Distribuição Tecidual , Transcrição Gênica
17.
Arch Insect Biochem Physiol ; 53(2): 49-65, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12761873

RESUMO

We describe here the cloning, expression, and characterization of a cDNA encoding the arylphorin-like hexameric storage protein from the mulberry longicorn beetle, Apriona germari (Coleoptera, Cerambycidae). The complete cDNA sequence of A. germari hexamerin (AgeHex) is comprised of 2,160 bp with 720 amino acid residues. The deduced protein sequence of AgeHex is most similar to Tenebrio molitor hexamerin2 (65.3%). Phylogenetic analysis further confirmed the AgeHex is more closely related to T. molitor hexmerin2 and T. molitor early-staged encapsulation inducing protein than to the other insect storage proteins. Southern blot analysis suggested the presence of A. germari hexamerin gene as a single copy and Northern blot analysis confirmed fat body-specific expression at the transcriptional level. The cDNA encoding AgeHex was expressed as a 80-kDa protein in the baculovirus-infected insect cells. Western blot analysis using the polyclonal antiserum against recombinant AgeHex indicated that the AgeHex corresponds to storage protein 2 (SP2) present in the A. germari larval hemolymph.


Assuntos
Besouros/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Sequência de Aminoácidos , Animais , Baculoviridae/genética , Sequência de Bases , Western Blotting , Células Cultivadas , Clonagem Molecular , Besouros/metabolismo , DNA Complementar/genética , DNA Complementar/metabolismo , Corpo Adiposo/metabolismo , Hemolinfa/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Tenebrio/genética , Transcrição Gênica
18.
Glycobiology ; 13(3): 147-57, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12626419

RESUMO

The structures of the oligosaccharides attached to arylphorin from Chinese oak silkworm, Antheraea pernyi, have been determined. Arylphorin, a storage protein present in fifth larval hemolymph, contained 4.8% (w/w) of carbohydrate that was composed of Fuc:GlcNAc:Glc:Man=0.2:4.0:1.4:13.6 moles per mole protein. Four moles of GlcNAc in oligomannose-type oligosaccharides strongly suggest that the protein contains two N-glycosylation sites. Normal-phase HPLC and mass spectrometry oligosaccharide profiles confirmed that arylphorin contained mainly oligomannose-type glycans as well as truncated mannose-type structures with or without fucosylation. Interestingly, the most abundant oligosaccharide was monoglucosylated Man9-GlcNAc2, which was characterized by normal-phase HPLC, mass spectrometry, Aspergillus saitoi alpha-mannosidase digestion, and 1H 600 MHz NMR spectrometry. This glycan structure is not normally present in secreted mammalian glycoproteins; however, it has been identified in avian species. The Glc1Man9GlcNAc2 structure was present only in arylphorin, whereas other hemolymph proteins contained only oligomannose and truncated oligosaccharides. The oligosaccharide was also detected in the arylphorin of another silkworm, Bombyx mori, suggesting a specific function for the Glc1Man9GlcNAc2 glycan. There were no processed glucosylated oligosaccharides such as Glc1Man5-8GlcNAc2. Furthermore, Glc1Man9GlcNAc2 was not released from arylophorin by PNGase F under nondenaturing conditions, suggesting that the N-glycosidic linkage to Asn is protected by the protein. Glc1Man9GlcNAc2 may play a role in the folding of arylphorin or in the assembly of hexamers.


Assuntos
Glucose/metabolismo , Glicoproteínas/química , Proteínas de Insetos/química , Lepidópteros/química , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Amidoidrolases/metabolismo , Animais , Bombyx , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Glicoproteínas/metabolismo , Hemolinfa/química , Proteínas de Insetos/metabolismo , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligossacarídeos/isolamento & purificação , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase
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