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1.
Vaccines (Basel) ; 11(7)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37515082

RESUMO

Rhipicephalus microplus economically impacts cattle production in tropical and subtropical countries. Application of acaricides constitutes the major control method; however, inadequate use has increased resistant tick populations, resulting in environmental and cattle product contamination. Anti-tick vaccines based on the Bm86 antigen are an environmentally friendly, safe, and economically sustainable alternative for controlling R. microplus infestations. Nevertheless, variable efficacy has been experienced against different geographic tick strains. Herein, we evaluated the efficacy of a conserved polypeptide Bm86 derived from a Mexican R. microplus strain previously characterized. Twelve cows were assigned to three experimental groups and immunized with three doses of the polypeptide Bm86 (pBm86), adjuvant/saline alone, and Bm86 antigen (control +), respectively. Specific IgG antibody levels were measured by ELISA and confirmed by Western blot. In addition, the reproductive performance of naturally infested R. microplus was also determined. The more affected parameter was the adult female tick number, with a reduction of 44% by the pBm86 compared to the controls (p < 0.05), showing a vaccine efficacy of 58%. Anti-pBm86 IgG antibodies were immunogenic and capable of recognizing the native Bm86 protein in the eggs, larvae, and guts of R. microplus. The negative correlation between antibody levels and the reduction of naturally tick-infested cattle suggested that the effect of the polypeptide Bm86 was attributed to the antibody response in immunized cattle. In conclusion, the polypeptide Bm86 showed a specific immune response in cattle and conferred protection against R. microplus in a Mexican tropical region. These findings support further experiments with this antigen to demonstrate its effectiveness as a regional vaccine.

2.
Molecules ; 26(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34770801

RESUMO

Clove (Syzygium aromaticum L. Myrtaceae) is an aromatic plant widely cultivated in tropical and subtropical countries, rich in volatile compounds and antioxidants such as eugenol, ß-caryophyllene, and α-humulene. Clove essential oil has received considerable interest due to its wide application in the perfume, cosmetic, health, medical, flavoring, and food industries. Clove essential oil has biological activity relevant to human health, including antimicrobial, antioxidant, and insecticidal activity. The impacts of the extraction method (hydrodistillation, steam distillation, ultrasound-assisted extraction, microwave-assisted extraction, cold pressing, and supercritical fluid extraction) on the concentration of the main volatile compounds in clove essential oil and organic clove extracts are shown. Eugenol is the major compound, accounting for at least 50%. The remaining 10-40% consists of eugenyl acetate, ß-caryophyllene, and α-humulene. The main biological activities reported are summarized. Furthermore, the main applications in clove essential oil in the food industry are presented. This review presents new biological applications beneficial for human health, such as anti-inflammatory, analgesic, anesthetic, antinociceptive, and anticancer activity. This review aims to describe the effects of different methods of extracting clove essential oil on its chemical composition and food applications and the biological activities of interest to human health.


Assuntos
Óleo de Cravo/química , Óleo de Cravo/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Syzygium/química , Anti-Infecciosos , Anti-Inflamatórios , Antineoplásicos Fitogênicos , Antioxidantes , Fracionamento Químico/métodos , Óleo de Cravo/isolamento & purificação , Suplementos Nutricionais , Aditivos Alimentares , Avaliação do Impacto na Saúde , Humanos , Óleos Voláteis/isolamento & purificação , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Relação Estrutura-Atividade
3.
Pharmaceutics ; 13(10)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34684012

RESUMO

Metal-based nanoparticles are widely used to deliver bioactive molecules and drugs to improve cancer therapy. Several research works have highlighted the synthesis of gold and silver nanoparticles by green chemistry, using biological entities to minimize the use of solvents and control their physicochemical and biological properties. Recent advances in evaluating the anticancer effect of green biogenic Au and Ag nanoparticles are mainly focused on the use of conventional 2D cell culture and in vivo murine models that allow determination of the half-maximal inhibitory concentration, a critical parameter to move forward clinical trials. However, the interaction between nanoparticles and the tumor microenvironment is not yet fully understood. Therefore, it is necessary to develop more human-like evaluation models or to improve the existing ones for a better understanding of the molecular bases of cancer. This review provides recent advances in biosynthesized Au and Ag nanoparticles for seven of the most common and relevant cancers and their biological assessment. In addition, it provides a general idea of the in silico, in vitro, ex vivo, and in vivo models used for the anticancer evaluation of green biogenic metal-based nanoparticles.

4.
Parasite ; 28: 65, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34533454

RESUMO

Rhipicephalus (Boophilus) microplus ticks are obligatory hematophagous ectoparasites of cattle and act as vectors for disease-causing microorganisms. Conventional tick control is based on the application of chemical acaricides; however, their uncontrolled use has increased resistant tick populations, as well as food and environmental contamination. Alternative immunological tick control has shown to be partially effective. Therefore, there is a need to characterize novel antigens in order to improve immunological protection. The aim of this work was to evaluate Cys-loop receptors as vaccine candidates. N-terminal domains of a glutamate receptor and of a glycine-like receptor were recombinantly produced in Escherichia coli. Groups of BALB/c mice were independently immunized with four doses of each recombinant protein emulsified with Freund's adjuvant. Both vaccine candidates were immunogenic in mice as demonstrated by western blot analysis. Next, recombinant proteins were independently formulated with the adjuvant Montanide ISA 50 V2 and evaluated in cattle infested with Rhipicephalus microplus tick larvae. Groups of three European crossbred calves were immunized with three doses of each adjuvanted protein. ELISA test was used to evaluate the IgG immune response elicited against the recombinant proteins. Results showed that vaccine candidates generated a moderate humoral response on vaccinated cattle. Vaccination significantly affected the number of engorged adult female ticks, having no significant effects on tick weight, egg weight and egg fertility values. Vaccine efficacies of 33% and 25% were calculated for the glutamate receptor and the glycine-like receptor, respectively.


TITLE: Évaluation de l'immunoprotection du domaine N-terminal recombinant des récepteurs Cys-loop contre l'infestation par les tiques Rhipicephalus (Boophilus) microplus. ABSTRACT: Les tiques Rhipicephalus (Boophilus) microplus sont des ectoparasites hématophages obligatoires des bovins et agissent comme vecteurs de micro-organismes pathogènes. Le contrôle conventionnel des tiques est basé sur l'application d'acaricides chimiques, mais leur utilisation incontrôlée a augmenté les populations de tiques résistantes ainsi que la contamination des aliments et de l'environnement. Le contrôle immunologique alternatif des tiques s'est avéré partiellement efficace. Par conséquent, il est nécessaire de caractériser de nouveaux antigènes afin d'améliorer la protection immunologique. Le but de ce travail était d'évaluer les récepteurs Cys-loop comme candidats vaccins. Les domaines N-terminaux d'un récepteur du glutamate et d'un récepteur de type glycine ont été produits par recombinaison chez Escherichia coli. Des groupes de souris BALB/c ont été immunisés indépendamment avec quatre doses de chaque protéine recombinante émulsionnée avec l'adjuvant de Freund. Les deux vaccins candidats étaient immunogènes chez la souris, comme l'a démontré l'analyse par transfert Western. Ensuite, des protéines recombinantes ont été formulées indépendamment avec l'adjuvant Montanide ISA 50 V2 et évaluées chez des bovins infestés de larves de tiques Rhipicephalus microplus. Des groupes de trois veaux croisés européens ont été immunisés avec trois doses de chaque protéine avec adjuvant. Le test ELISA a été utilisé pour évaluer la réponse immunitaire IgG induite contre les protéines recombinantes. Les résultats ont montré que les candidats vaccins généraient une réponse humorale modérée sur les bovins vaccinés. La vaccination a affecté de manière significative le nombre de tiques femelles adultes engorgées mais n'a eu aucun effet significatif sur le poids des tiques, le poids des œufs et les valeurs de fertilité des œufs. Des efficacités vaccinales de 33 % et 25 % ont été calculées pour le récepteur du glutamate et le récepteur de type glycine, respectivement.


Assuntos
Doenças dos Bovinos , Receptores de Canais Iônicos de Abertura Ativada por Ligante com Alça de Cisteína , Rhipicephalus , Infestações por Carrapato , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterinária
5.
Molecules ; 26(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34361589

RESUMO

Virus-like particles are excellent inducers of the adaptive immune response of humans and are presently being used as scaffolds for the presentation of foreign peptides and antigens derived from infectious microorganisms for subunit vaccine development. The most common approaches for peptide and antigen presentation are translational fusions and chemical coupling, but some alternatives that seek to simplify the coupling process have been reported recently. In this work, an alternative platform for coupling full antigens to virus-like particles is presented. Heterodimerization motifs inserted in both Tobacco etch virus coat protein and green fluorescent protein directed the coupling process by simple mixing, and the obtained complexes were easily taken up by a macrophage cell line.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos , Potyvirus , Vacinas de Partículas Semelhantes a Vírus , Animais , Antígenos/química , Antígenos/imunologia , Camundongos , Potyvirus/química , Potyvirus/imunologia , Células RAW 264.7 , Vacinas de Partículas Semelhantes a Vírus/química , Vacinas de Partículas Semelhantes a Vírus/imunologia
6.
Biosensors (Basel) ; 10(10)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096879

RESUMO

Background: Several studies have shown that patients with cancer have antibodies in serum that react with cellular autoantigens, known as Tumor-Associated Antigens (TAA). The present work aimed to determine whether a mini-array comprising four recombinant TAA increases the detection of specific serum antibodies for the diagnosis of early-stage breast cancer. Methods: The mini-array included Alpha 1-AntiTrypsin (A1AT), TriosePhosphate Isomerase 1 (TPI1), Peptidyl-Prolyl cis-trans Isomerase A (PPIA), and PeroxiReDoXin 2 (PRDX2) full-length recombinant proteins. The proteins were produced after gene cloning, expression, and purification, and were verified by Western blot assays. Then, Dot-Blot was performed to find antibodies against the four TAA in 12 sera from women with early-stage breast cancer (stage II) and 12 sera from healthy women. Results: Antibody detection against individual TAA in early-stage breast cancer sera ranged from 58.3% to 83.3%. However, evaluation of the four TAA showed that there was a positive antibody reaction reaching a sensitivity of 100% and a specificity of 85% in early-stage breast cancer, suggesting that this mini-array must be evaluated as a clinical diagnostic tool for early-stage breast cancer in a larger sample size. Conclusion: Our results suggest that TAA mini-arrays may provide a promising and powerful method for improving the detection of breast cancer in Mexican women.


Assuntos
Biomarcadores Tumorais/análise , Técnicas Biossensoriais , Neoplasias da Mama/diagnóstico , Soro/química , Adulto , Antígenos de Neoplasias , Neoplasias da Mama/sangue , Feminino , Testes Hematológicos , Humanos , Pessoa de Meia-Idade
7.
Exp Parasitol ; 201: 26-33, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31029699

RESUMO

The cattle tick Rhipicephalus (Boophilus) microplus is one of the most important ectoparasites for livestock in tropical and subtropical areas around the world. This tick economically impacts cattle production by reducing weight gain and milk production. Moreover, it is a vector of pathogens causing diseases such as babesiosis and anaplasmosis. Conventional tick control relies mainly on the use of chemical acaricides; however, their intensive use has led to the rapid appearance of resistant tick populations. It is therefore necessary to look for alternative tick control products. In that sense, plant extracts might represent a promising source of new acaricides. Previously, we reported a significant acaricide effect of essential oils from selected plant species. In the present study, we used a mixture design approach to develop phyto-formulations by combining individual essential oils. We produced several mixtures at 10% containing different proportions of individual essential oils (ranging from 0 to 1) from cinnamon (Cinnamomum zeylanicum), cumin (Cuminum cyminum) and allspice (Pimenta dioica) and tested their acaricidal activity against R. microplus ticks by means of larval packet test (LPT) and adult immersion test (AIT) assays. The optimal mixture predicted against R. microplus was composed of 66%, 17% and 17% of essential oils from C. zeylanicum, C. cyminum and P. dioica, respectively. We generated an estimated response surface contour plot that estimates 80%-100% acaricidal efficacy. In the optimal mixture 34 compounds were identified, which represent 98.65% of the total composition, with cinnamaldehyde (37.77%), ß-caryophyllene (13.92%), methyl eugenol (12.27%) and cuminaldehyde (8.99%) being the major components. Next, we developed emulsions by combining the optimal mixture with several surfactants and determined particle size, Zeta potential, stability and bioactivity. Emulsions containing 2% and 5% Tween 20 or Tween 80 remain stable after 14 days at 54 °C. Finally, optimized emulsion retained a high acaricidal activity against larval and adult R. microplus ticks. Taken together, our findings showed the usefulness of mixture design method for the development of essential oil mixtures with potent acaricidal activity. These formulations have the potential to successfully control tick infestations.


Assuntos
Doenças dos Bovinos/prevenção & controle , Óleos Voláteis , Extratos Vegetais , Rhipicephalus , Controle de Ácaros e Carrapatos/métodos , Infestações por Carrapato/veterinária , Acaricidas , Análise de Variância , Animais , Vetores Aracnídeos , Bovinos , Doenças dos Bovinos/parasitologia , Cinnamomum zeylanicum/química , Misturas Complexas/química , Cuminum/química , Emulsões/química , Feminino , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/química , Pimenta/química , Extratos Vegetais/química , Sementes/química , Infestações por Carrapato/prevenção & controle
8.
Int J Biochem Cell Biol ; 104: 133-137, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30236992

RESUMO

Human ß-defensin 1 (hBD-1) is a multifaceted antimicrobial peptide being a tumour suppressor and, depending on call of duty, capable of inducing self-nets and neutrophil extracellular traps (NETs) to capture and/or kill bacteria, participates in inflammatory responses in chronic diseases including hBD-3 upregulation and also capable of up/downregulation in the presence of certain species of Lactobacillus sp. Thus, is regulated by host microbiota. Alleles, genotypes and/or altered gene expression of its coding gene, DEFB1, have been associated with several human diseases/conditions ranging from metabolic/chronic (e.g. cancer), infectious (e.g. tuberculosis, HIV/AIDS), inflammatory (gastrointestinal diseases), male infertility and more recently, neurologic (e.g. depression and Alzheimer) and autoimmune diseases (e.g. vitiligo and systemic lupus erythematosus). The present update focuses on novel DEFB1/hBD-1 properties and biomarker features, its biological function and the pharmaceutical potential uses of antimicrobial peptide elicitors (APEs) or the engineered peptide in the treatment of hBD-1-related human diseases.


Assuntos
beta-Defensinas/metabolismo , Regulação da Expressão Gênica , Humanos , Indústrias , beta-Defensinas/química , beta-Defensinas/genética
9.
Exp Parasitol ; 170: 227-235, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27729251

RESUMO

Rhipicephalus (Boophilus) microplus ticks are obligatory hematophagous ectoparasites of cattle and act as vectors for disease-causing microorganisms. Conventional tick control is based on the use of chemical acaricides; however, their uncontrolled use has increased tSresistant tick populations, as well as food and environmental contamination. Alternative immunological tick control has shown to be partially effective. The only anti-tick vaccine commercially available at present in the world is based on intestinal Bm86 protein, and shows a variable effectiveness depending on tick strains or geographic isolates. Therefore, there is a need to characterize new antigens in order to improve immunological protection. The aim of this work was to identify immunogenic proteins from ovarian tissue extracts of R. microplus, after cattle immunization. Results showed that ovarian proteins complexed with the adjuvant Montanide ISA 50 V generated a strong humoral response on vaccinated cattle. IgG levels peaked at fourth post-immunization week and remained high until the end of the experiment. 1D and 2D SDS-PAGE-Western blot assays with sera from immunized cattle recognized several ovarian proteins. Reactive bands were cut and analyzed by LC-MS/MS. They were identified as Vitellogenin, Vitellogenin-2 precursor and Yolk Cathepsin. Our findings along with bioinformatic analysis indicate that R. microplus has several Vitellogenin members, which are proteolytically processed to generate multiple polypeptide fragments. This apparent complexity of vitellogenic tick molecular targets gives the opportunity to explore their potential usefulness as vaccine candidates but, at the same time, imposes a challenge on the selection of the appropriate set of antigens.


Assuntos
Vetores Aracnídeos/imunologia , Proteínas de Artrópodes/imunologia , Rhipicephalus/imunologia , Controle de Ácaros e Carrapatos/métodos , Animais , Western Blotting , Bovinos , Doenças dos Bovinos/prevenção & controle , DNA Complementar/biossíntese , Eletroforese/métodos , Desenvolvimento Embrionário/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulina G/sangue , Larva/imunologia , Oogênese/imunologia , Ovário/imunologia , Reação em Cadeia da Polimerase , Proteômica/métodos , RNA/genética , RNA/isolamento & purificação , Reprodução/imunologia , Espectrometria de Massas em Tandem , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterinária , Vacinas , Vitelogeninas/biossíntese , Vitelogeninas/imunologia
10.
Parasite ; 21: 43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25174962

RESUMO

The cattle tick Rhipicephalus (Boophilus) microplus is the most economically important ectoparasite affecting the cattle industry in tropical and subtropical areas around the world. The principal method of tick control has relied mainly on the use of chemical acaricides, including ivermectin; however, cattle tick populations resistant to ivermectin have recently been reported in Brazil, Mexico, and Uruguay. Currently, the molecular basis for ivermectin susceptibility and resistance are not well understood in R. microplus. This prompted us to search for potential molecular targets for ivermectin. Here, we report the cloning and molecular characterization of a R. microplus glycine-like receptor (RmGlyR) gene. The characterized mRNA encodes for a 464-amino acid polypeptide, which contains features common to ligand-gated ion channels, such as a large N-terminal extracellular domain, four transmembrane domains, a large intracellular loop and a short C-terminal extracellular domain. The deduced amino acid sequence showed around 30% identity to GlyRs from some invertebrate and vertebrate organisms. The polypeptide also contains the PAR motif, which is important for forming anion channels, and a conserved glycine residue at the third transmembrane domain, which is essential for high ivermectin sensitivity. PCR analyses showed that RmGlyR is expressed at egg, larval and adult developmental stages. Our findings suggest that the deduced receptor is an additional molecular target to ivermectin and it might be involved in ivermectin resistance in R. microplus.


Assuntos
Proteínas de Artrópodes/genética , Receptores de Glicina/genética , Rhipicephalus/genética , Acaricidas/farmacologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/metabolismo , Sequência de Bases , Sítios de Ligação , Clonagem Molecular , DNA Complementar/genética , Resistência a Medicamentos/genética , Escherichia coli , Regulação da Expressão Gênica no Desenvolvimento , Canais Iônicos/genética , Canais Iônicos/metabolismo , Ivermectina/farmacologia , Larva , Dados de Sequência Molecular , Óvulo , RNA Mensageiro/genética , Receptores de Glicina/metabolismo , Rhipicephalus/crescimento & desenvolvimento , Rhipicephalus/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
11.
Future Oncol ; 10(8): 1501-13, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25052758

RESUMO

Considerable efforts have been undertaken to produce an effective screening method to reduce lung cancer mortality. Imaging tools such as low-dose computed tomography has shown an increase in the detection of early disease and a reduction in the rate of death. This screening modality has, however, several limitations, such as overdiagnosis and a high rate of false positives. Therefore, new screening methods, such as the use of circulating protein biomarkers, have emerged as an option that could complement imaging studies. In this review, current imaging techniques applied to lung cancer screening protocols are presented, as well as up-to-date status of circulating protein biomarker panels that may improve lung cancer diagnosis. Additionally, diverse statistical and artificial intelligence tools applied to the design and optimization of these panels are discussed along with the presentation of two commercially available blood tests recently developed to help detect lung cancer early.


Assuntos
Biomarcadores/sangue , Proteínas Sanguíneas , Detecção Precoce de Câncer , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Diagnóstico por Imagem/métodos , Detecção Precoce de Câncer/métodos , Humanos , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Electrophoresis ; 33(14): 2130-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22821488

RESUMO

Several studies have demonstrated that sera from patients with cancer contain antibodies that recognize a unique group of autologous antigens called tumor-associated antigens (TAA). In the current study, we employed an immunoproteomic approach, combining 2DE, Western blot, and MALDI-MS to identify TAA in the sera of patients diagnosed with infiltrating ductal or in situ carcinoma breast cancer. Sera obtained from 25 newly diagnosed patients with stage II breast cancer and 20 healthy volunteers was evaluated for the presence of novel TAA. Alpha 1-antitrypsin (A1AT) antibodies were detected in 24 of 25 patients with breast cancer (96%) and in 2 of 20 controls (10%). Sensitivity of detection of autoantibodies against A1AT in patients with breast cancer was 96%. Our preliminary results suggest that A1AT and autoantibodies against alpha 1 antitrypsin may be useful serum biomarkers for early-stage breast cancer screening and diagnosis.


Assuntos
Antígenos de Neoplasias/sangue , Autoanticorpos/sangue , Neoplasias da Mama/sangue , Carcinoma in Situ/sangue , Carcinoma Ductal de Mama/sangue , alfa 1-Antitripsina/sangue , Adulto , Anticorpos/sangue , Anticorpos/imunologia , Antígenos de Neoplasias/imunologia , Autoanticorpos/imunologia , Western Blotting , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/imunologia , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/imunologia , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/imunologia , Eletroforese em Gel Bidimensional , Feminino , Humanos , Pessoa de Meia-Idade , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , alfa 1-Antitripsina/imunologia
13.
Antonie Van Leeuwenhoek ; 102(2): 247-55, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22535436

RESUMO

During ethanol fermentation, yeast cells are exposed to stress due to the accumulation of ethanol, cell growth is altered and the output of the target product is reduced. For Agave beverages, like tequila, no reports have been published on the global gene expression under ethanol stress. In this work, we used microarray analysis to identify Saccharomyces cerevisiae genes involved in the ethanol response. Gene expression of a tequila yeast strain of S. cerevisiae (AR5) was explored by comparing global gene expression with that of laboratory strain S288C, both after ethanol exposure. Additionally, we used two different culture conditions, cells grown in Agave tequilana juice as a natural fermentation media or grown in yeast-extract peptone dextrose as artificial media. Of the 6368 S. cerevisiae genes in the microarray, 657 genes were identified that had different expression responses to ethanol stress due to strain and/or media. A cluster of 28 genes was found over-expressed specifically in the AR5 tequila strain that could be involved in the adaptation to tequila yeast fermentation, 14 of which are unknown such as yor343c, ylr162w, ygr182c, ymr265c, yer053c-a or ydr415c. These could be the most suitable genes for transforming tequila yeast to increase ethanol tolerance in the tequila fermentation process. Other genes involved in response to stress (RFC4, TSA1, MLH1, PAU3, RAD53) or transport (CYB2, TIP20, QCR9) were expressed in the same cluster. Unknown genes could be good candidates for the development of recombinant yeasts with ethanol tolerance for use in industrial tequila fermentation.


Assuntos
Agave/microbiologia , Bebidas Alcoólicas/microbiologia , Etanol/metabolismo , Perfilação da Expressão Gênica , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Agave/metabolismo , Fermentação , Proteínas de Saccharomyces cerevisiae/metabolismo
14.
Cell Signal ; 19(6): 1212-20, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17320350

RESUMO

Smac/DIABLO is a mitochondrial protein that participates in apoptotic cell death by means of sequestering several members of the inhibitor of apoptosis protein family. This action allows caspase activation, cleavage of key cellular substrates and death. Release from mitochondria is considered the main regulatory step of Smac/DIABLO activity. Nevertheless, the fact that at least one isoform, Smac-beta, does not reside in this organelle implies that transcriptional regulation could also be important. cAMP is a well known second messenger with important apoptotic effects. To analyze if cAMP could be involved in Smac/DIABLO gene regulation, we analyzed 2903 base pairs upstream of the coding sequence and characterized the minimal promoter, which contains a consensus CRE site. We found that cAMP/PKA/CREB pathway is indeed an important regulator of Smac/DIABLO transcription, since exposure to the cAMP analog 8-CPT-cAMP, the adenylyl cyclase activator forskolin, the inhibitor of phosphodiesterase isobutylmethylxanthine or by hindering PKA activation with H89, regulated the promoter activity, as shown by gene reporter and RT-PCR assays. Additionally, the results of site-directed mutagenesis revealed that the consensus CRE site was biologically functional and required for cAMP-induced promoter activity in human HeLa cells. Supporting these results, a negative dominant version of the protein kinase A responsive factor, KCREB, reduced basal Smac/DIABLO expression and rendered the promoter unresponsive to cAMP. Reducing Smac expression using an antisense approach blocked the apoptosis effects of cAMP in cervical cancer cells. These results show that cAMP is an important modulator of the apoptotic threshold in cancer cell by means of regulating Smac/DIABLO expression.


Assuntos
Apoptose/efeitos dos fármacos , AMP Cíclico/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Mitocondriais/genética , Transcrição Gênica/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Região 5'-Flanqueadora/genética , Proteínas Reguladoras de Apoptose , Sequência de Bases , Clonagem Molecular , Células HeLa , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Deleção de Sequência
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