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1.
Int J Obes (Lond) ; 39(11): 1662-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26238973

RESUMO

Body mass index (BMI) is a non-invasive measurement of obesity. It is commonly used for assessing adiposity and obesity-related risk prediction. Genetic differences between ethnic groups are important factors, which contribute to the variation in phenotypic effects. India inhabited by the first out-of-Africa human population and the contemporary Indian populations are admixture of two ancestral populations; ancestral north Indians (ANI) and ancestral south Indians (ASI). Although ANI are related to Europeans, ASI are not related to any group outside Indian-subcontinent. Hence, we expect novel genetic loci associated with BMI. In association analysis, we found eight genic SNPs in extreme of distribution (P⩽3.75 × 10(-5)), of which WWOX has already been reported to be associated with obesity-related traits hence excluded from further study. Interestingly, we observed rs1526538, an intronic SNP of THSD7A; a novel gene significantly associated with obesity (P=2.88 × 10(-5), 8.922 × 10(-6) and 2.504 × 10(-9) in discovery, replication and combined stages, respectively). THSD7A is neural N-glycoprotein, which promotes angiogenesis and it is well known that angiogenesis modulates obesity, adipose metabolism and insulin sensitivity, hence our result find a correlation. This information can be used for drug target, early diagnosis of obesity and treatment.


Assuntos
Etnicidade/genética , Obesidade/etnologia , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Trombospondinas/genética , População Branca/genética , Adulto , Índice de Massa Corporal , Feminino , Variação Genética , Genética Populacional , Estudo de Associação Genômica Ampla , Humanos , Índia/epidemiologia , Desequilíbrio de Ligação , Masculino , Obesidade/epidemiologia , Fenótipo , População Branca/estatística & dados numéricos
2.
J Neurooncol ; 107(2): 289-97, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22102081

RESUMO

The search for molecular markers which predict response to chemotherapy is an important aspect of current neuro-oncology research. MGMT promoter methylation is the only proved marker of glioblastoma. The purpose of this study was to assess the effect of topoisomerase expression on glioblastoma survival and study the mechanisms involved. The transcript levels of all isoforms of the topoisomerase family in all grades of diffuse astrocytoma were assessed. A prospective study of patients with glioblastoma treated by a uniform treatment procedure was performed with the objective of correlating outcome with gene expression. The ability of TOP2A enzyme to relax the super coiled plasmid DNA in the presence of temozolomide was evaluated to assess its effect on TOP2A. The temozolomide cyctotoxicity of TOP2A-silenced U251 cells was assessed. The transcript levels of TOP2A, TOP2B, and TOP3A are upregulated significantly in GBM in comparison with lower grades of astrocytoma and normal brain samples. mRNA levels of TOP2A correlated significantly with survival of the patients. Higher TOP2A transcript levels in GBM patients predicted better prognosis (P = 0.043; HR = 0.889). Interestingly, we noted that temozolomide inhibited TOP2A activity in in-vitro enzyme assays. We also noted that siRNA knock down of TOP2A rendered a glioma cell line resistant to temozolomide chemotherapy. We demonstrated for the first time that temozolomide is also a TOP2A inhibitor and established that TOP2A transcript levels determine the chemosensitivity of glioblastoma to temozolomide therapy. Very high levels of TOP2A are a good prognostic indicator in GBM patients receiving temozolomide chemotherapy.


Assuntos
Antígenos de Neoplasias/metabolismo , Neoplasias Encefálicas/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Dacarbazina/análogos & derivados , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Inibidores da Topoisomerase II/farmacologia , Antígenos de Neoplasias/genética , Antineoplásicos/farmacologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidade , Camptotecina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Estudos de Coortes , DNA Topoisomerases Tipo II/genética , Proteínas de Ligação a DNA/genética , Dacarbazina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Glioblastoma/diagnóstico , Glioblastoma/mortalidade , Humanos , Masculino , Proteínas de Ligação a Poli-ADP-Ribose , Prognóstico , RNA Mensageiro/metabolismo , Temozolomida
4.
J Cell Biol ; 105(1): 457-63, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3475276

RESUMO

Transforming growth factor-type beta (TGF-beta) has been identified as a constituent of bone matrix (Seyedin, S. M., A. Y. Thompson, H. Bentz, D. M. Rosen, J. M. McPherson, A. Conti, N. R. Siegel, G. R. Gallupi, and K. A. Piez, 1986, J. Biol. Chem. 261:5693-5695). We used both developing bone and bone-forming cells in vitro to demonstrate the cellular origin of this peptide. TGF-beta mRNA was detected by Northern analysis in both developing bone tissue and fetal bovine bone-forming cells using human cDNA probes. TGF-beta was shown to be synthesized and secreted by metabolically labeled bone cell cultures by immunoprecipitation from the medium. Further, TGF-beta activity was demonstrated in conditioned media from these cultures by competitive radioreceptor and growth promotion assays. Fetal bovine bone cells (FBBC) were found to have relatively few TGF-beta receptors (5,800/cell) with an extremely low Kd of 2.2 pM (high binding affinity). In contrast to its inhibitory effects on the growth of many cell types including osteosarcoma cell lines, TGF-beta stimulated the growth of subconfluent cultures of FBBC; it had little effect on the production of collagen by these cells. We conclude that bone-forming cells are a source for the TGF-beta that is found in bone, and that these cells may be modulated by this factor in an autocrine fashion.


Assuntos
Osteoblastos/metabolismo , Biossíntese Peptídica , Animais , Reabsorção Óssea/efeitos dos fármacos , Bovinos , Células Cultivadas , DNA/genética , Marcadores Genéticos , Osteoblastos/efeitos dos fármacos , Osteossarcoma/patologia , Peptídeos/farmacologia , Fenótipo , RNA Mensageiro/análise , Ratos , Fatores de Crescimento Transformadores
5.
J Periodontal Res ; 44(5): 673-82, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19364390

RESUMO

BACKGROUND AND OBJECTIVE: Arecoline, an arecanut alkaloid present in the saliva of betel quid chewers, has been implicated in the pathogenesis of a variety of inflammatory oral diseases, including oral submucous fibrosis and periodontitis. To understand the molecular basis of arecoline action in epithelial changes associated with these diseases, we investigated the effects of arecoline on human keratinocytes with respect to cell growth regulation and the expression of stress-responsive genes. MATERIAL AND METHODS: Human keratinocyte cells (of the HaCaT cell line) were treated with arecoline, following which cell viability was assessed using the Trypan Blue dye-exclusion assay, cell growth and proliferation were analyzed using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) and 5-bromo-2-deoxyuridine incorporation assays, cell cycle arrest and generation of reactive oxygen species were examined using flow cytometry, and gene expression changes were investigated using the reverse transcription-polymerase chain reaction technique. The role of oxidative stress, muscarinic acetylcholine receptor and mitogen-activated protein kinase (MAPK) pathways were studied using specific inhibitors. Western blot analysis was performed to study p38 MAPK activation. RESULTS: Arecoline induced the generation of reactive oxygen species and cell cycle arrest at the G1/G0 phase in HaCaT cells without affecting the expression of p21/Cip1. Arecoline-induced epithelial cell death at higher concentrations was caused by oxidative trauma without eliciting apoptosis. Sublethal concentrations of arecoline upregulated the expression of the following stress-responsive genes: heme oxygenase-1; ferritin light chain; glucose-6-phosphate dehydrogenase; glutamate-cysteine ligase catalytic subunit; and glutathione reductase. Additionally, there was a dose-dependent induction of interleukin-1alfa mRNA by arecoline via oxidative stress and p38 MAPK activation. CONCLUSION: Our data highlight the role of oxidative stress in arecoline-mediated cell death, gene regulation and inflammatory processes in human keratinocytes.


Assuntos
Arecolina/farmacologia , Agonistas Colinérgicos/farmacologia , Queratinócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Apoferritinas , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Corantes , Inibidor de Quinase Dependente de Ciclina p21/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosefosfato Desidrogenase/efeitos dos fármacos , Glutamato-Cisteína Ligase/efeitos dos fármacos , Glutationa Redutase/efeitos dos fármacos , Heme Oxigenase-1/efeitos dos fármacos , Humanos , Interleucina-1alfa/biossíntese , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Estresse Oxidativo/genética , Inibidores de Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/análise , Receptores Muscarínicos/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacos
6.
J Periodontal Res ; 44(6): 736-43, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19438976

RESUMO

BACKGROUND AND OBJECTIVE: Oral submucous fibrosis, a disease of collagen disorder, has been attributed to arecoline present in the saliva of betel quid chewers. However, the molecular basis of the action of arecoline in the pathogenesis of oral submucous fibrosis is poorly understood. The basic aim of our study was to elucidate the mechanism underlying the action of arecoline on the expression of genes in oral fibroblasts. MATERIAL AND METHODS: Human keratinocytes (HaCaT cells) and primary human gingival fibroblasts were treated with arecoline in combination with various pathway inhibitors, and the expression of transforming growth factor-beta isoform genes and of collagen isoforms was assessed using reverse transcription-polymerase chain reaction analysis. RESULTS: We observed the induction of transforming growth factor-beta2 by arecoline in HaCaT cells and this induction was found to be caused by activation of the M-3 muscarinic acid receptor via the induction of calcium and the protein kinase C pathway. Most importantly, we showed that transforming growth factor-beta2 was significantly overexpressed in oral submucous fibrosis tissues (p = 0.008), with a median of 2.13 (n = 21) compared with 0.75 (n = 18) in normal buccal mucosal tissues. Furthermore, arecoline down-regulated the expression of collagens 1A1 and 3A1 in human primary gingival fibroblasts; however these collagens were induced by arecoline in the presence of spent medium of cultured human keratinocytes. Treatment with a transforming growth factor-beta blocker, transforming growth factor-beta1 latency-associated peptide, reversed this up-regulation of collagen, suggesting a role for profibrotic cytokines, such as transforming growth factor-beta, in the induction of collagens. CONCLUSION: Taken together, our data highlight the importance of arecolineinduced epithelial changes in the pathogenesis of oral submucous fibrosis.


Assuntos
Arecolina/farmacologia , Agonistas Colinérgicos/farmacologia , Matriz Extracelular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Linhagem Celular , Quelantes/farmacologia , Colágeno/efeitos dos fármacos , Colágeno/genética , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Colágeno Tipo III/efeitos dos fármacos , Colágeno Tipo III/genética , Colágeno Tipo IV/efeitos dos fármacos , Colágeno Tipo IV/genética , Colágeno Tipo VI/efeitos dos fármacos , Colágeno Tipo VI/genética , Colágeno Tipo VII/efeitos dos fármacos , Colágeno Tipo VII/genética , Regulação para Baixo , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Matriz Extracelular/genética , Gengiva/citologia , Humanos , Mucosa Bucal/patologia , Fibrose Oral Submucosa/genética , Fibrose Oral Submucosa/patologia , Isoformas de Proteínas/efeitos dos fármacos , Isoformas de Proteínas/genética , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/efeitos dos fármacos , Proteína Quinase C/genética , Receptor Muscarínico M3/efeitos dos fármacos , Receptor Muscarínico M3/genética , Estaurosporina/farmacologia , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta2/efeitos dos fármacos , Fator de Crescimento Transformador beta2/genética
7.
J Parasit Dis ; 40(4): 1627-1630, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27876998

RESUMO

Birds reared in backyard poultry farming system are more prone to parasitic infestation resulting in economic losses to rural community. The present study reports occurrence of Knemidokoptes mutans and Laminosioptes cysticola mites in a male Aseel bird. Clinical signs observed in the affected bird include hyperkeratosis with whitish film layer on shank and hock region of legs. Focal areas of sloughing of skin with oozing of blood were also observed on the back and on the legs. Examination of skin scrapings from the affected sites revealed different developmental stages of Knemidokoptes mutans and Laminosioptes cysticola mites. This paper reports occurrence of L. cysticola for the first time from India. The bird was treated with ivermectin injection through intramuscular route.

8.
Mech Dev ; 95(1-2): 207-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10906463

RESUMO

Members of the transforming growth factor-beta (TGF-beta) superfamily play various roles during development in both vertebrates and invertebrates. Two isoforms, TGF-beta2 and -beta5, have been isolated from Xenopus laevis. We describe here the localization of TGF-beta5 mRNA in early embryos of X. laevis, assessed by whole-mount in situ hybridization. The first detectable expression of TGF-beta5 was seen in the stage 14 embryo at the posterior tip of notochord, which continued to later stages, accompanied by the expression in bilateral regions of posterior wall in the tail region next to the notochord. At later stages, transient expression was seen in the cement gland (around stage 21) and in the somites (stages 24-27). In addition, expression was present in the branchial arches (stage 29-36) and olfactory placodes (stage 36).


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Fator de Crescimento Transformador beta/genética , Xenopus laevis/embriologia , Xenopus laevis/genética , Animais , Embrião não Mamífero/embriologia , RNA Mensageiro/análise , RNA Mensageiro/genética
9.
Mol Endocrinol ; 2(8): 747-55, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3211158

RESUMO

Transforming growth factor beta 1 (TGF beta 1) has been purified and the mRNA cloned from a number of mammalian species including human, murine, bovine, porcine, and simian. Using a human TGF beta 1 cDNA probe, we have detected two distinct TGF beta RNAs in cultured primary chick embryo chondrocytes. One of these RNAs, migrating at about 1.7 kilobases, shows similarity to mammalian TGF beta 1. The second RNA, migrating at about 3 kilobases, is a novel TGF beta mRNA which we have named TGF beta 3. Clones corresponding to each of these RNAs were isolated from a cultured primary chick embryo chondrocyte cDNA library. Two cDNA clones for TGF beta 3, pTGFB-ChX17 and pTGFB-ChX25, contained a 39 nucleotide-long 5'-untranslated region, a 1236 nucleotide-long coding region, and a 911 nucleotide-long 3'-untranslated region. The predicted protein includes a signal peptide of 20-23 amino acids as in human TGF beta 1 and 2, and a precursor protein consisting of 412 amino acids, which can be cleaved at a lys-arg site to produce a 112 amino acid processed peptide containing nine cysteine residues in the same positions as in human TGF beta 1 and 2. At the nucleotide level, the processed coding region of TGF beta 3 shows 72% and 76% identity with the processed coding regions of human TGF beta 1 and TGF beta 2, respectively; at the amino acid level, TGF beta 3 shows 76% identity with TGF beta 1 and 79% identity with TGF beta 2.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cartilagem/metabolismo , DNA/genética , RNA Mensageiro/genética , Fatores de Crescimento Transformadores/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Embrião de Galinha , Clonagem Molecular , Genes , Humanos , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico
10.
Mol Endocrinol ; 2(11): 1056-63, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2464748

RESUMO

Human transforming growth factor alpha (TGF alpha) is coded for by an mRNA of about 4800 nucleotides. The cDNA sequence demonstrates that the 50 amino acid TGF alpha is embedded in a larger 160 amino acid precursor protein. We report here that in addition to the 4800 nucleotide TGF alpha mRNA, there is a novel second RNA species of about 350 nucleotides that hybridizes to a human TGF alpha cDNA probe. This small RNA species has been found in the RNA of several human tumor cells including HT1080, A549, A431, A2058, and A673. We have demonstrated an inverse relationship between the amounts of the 4800 nucleotide TGF alpha mRNA and the 350 nucleotide novel RNA in these human cells. Restriction enzyme cleavage of a human TGF alpha cDNA probe into three separate domains consisting of a processed coding region and 5'- and 3'-preprocessed coding and untranslated regions showed that only the 3'-untranslated region hybridized to the 350 nucleotide RNA. Using sense and anti-sense single-stranded 3'-untranslated region probes, we determined that the 350 nucleotide RNA band may be composed of multiple species of RNA which are related to the anti-sense DNA strand that is opposite to the strand that codes for the 4800 nucleotide TGF alpha mRNA.


Assuntos
RNA Mensageiro/análise , RNA/análise , Fatores de Crescimento Transformadores/genética , Sequência de Bases , Linhagem Celular , DNA/análise , Sondas de DNA , Humanos , Dados de Sequência Molecular , Peso Molecular , Hibridização de Ácido Nucleico , RNA Mensageiro/isolamento & purificação , Células Tumorais Cultivadas/análise
11.
Mol Endocrinol ; 1(10): 693-8, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3153459

RESUMO

Transforming growth factor-beta 1 (TGF beta 1) has been purified from a number of different sources and has a broad species specificity. To deduce the complete amino acid sequence of bovine TGF beta 1 we have isolated cDNA clones encoding the protein from a bovine fibropapilloma library using a human cDNA probe. Sequence analysis of two independent cDNA clones revealed that the 112 amino acids corresponding to bovine TGF beta 1 are identical to those of the human and porcine proteins. This unusually high degree of conservation in the primary structure of the human and bovine proteins reflects the strong evolutionary constraints for maintenance of structure and function of the molecule. As in the human, murine, and porcine systems, the mature form of TGF beta 1 is derived by proteolytic cleavage of a larger precursor. Small differences in amino acid sequence were observed in the portion of the precursor that does not include mature TGF beta 1, although 92% of the residues are still conserved. A 2.25 kilobase (kb) mRNA was identified in total bovine wart and bone RNA, whereas no message was detected in polyadenylated spleen or brain RNA. In addition to the major 2.25 kb message, we observed a 1.9 kb transcript in poly(A+) RNA from wart tissue.


Assuntos
Fator de Crescimento Transformador beta/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Bovinos , Clonagem Molecular , DNA/genética , DNA/isolamento & purificação , Dados de Sequência Molecular , RNA Mensageiro/biossíntese , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
12.
J Parasit Dis ; 39(2): 238-40, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26064007

RESUMO

A total of 937 dogs were screened for Trypanosoma evansi infection by wet blood film, blood smear staining techniques and micro haematocrit centrifugation technique (MHCT). In the present study, 2.28 % of male dogs and 2.40 % of female dogs were found positive by MHCT method. The findings indicated that there was no effect of T. evansi infection on sex of dogs. Higher prevalence of T. evansi infection was observed in Mongrel than in Pomeranian, Cross breeds, German Shepherd, Doberman and Labrador breeds. Age wise prevalence of T. evansi infection in dogs revealed that younger ones, below the 2 years age group recorded the highest prevalence than the above the 2 years age group dogs.

13.
Gene ; 208(2): 323-9, 1998 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-9524286

RESUMO

Transforming growth factors-beta are potent regulators of cellular proliferation, differentiation and morphogenesis. 2.41 kb of the 5' flanking region of the transforming growth factor-beta 5 (TGF-beta 5) gene has been isolated from a Xenopus laevis genomic library and sequenced. The transcription start site of this gene was determined by 5' RACE method. Promoter activity was demonstrated by transient transfection experiments using luciferase reporter gene constructs in XTC cells. A number of putative recognition sites for transcription factors were found in the 5' flanking region of the TGF-beta 5 gene.


Assuntos
Regiões Promotoras Genéticas , Precursores de Proteínas/biossíntese , Precursores de Proteínas/genética , Sequências Reguladoras de Ácido Nucleico , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/genética , Xenopus laevis/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Primers do DNA , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Biblioteca Genômica , Dados de Sequência Molecular , Precursores de Proteínas/química , Mapeamento por Restrição , Transcrição Gênica , Fator de Crescimento Transformador beta/química
14.
Gene ; 191(1): 103-7, 1997 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-9210595

RESUMO

Transforming Growth Factors-beta (TGF-betas) have been described in many vertebrate species of amphibians, aves and mammals. In this report we demonstrate the presence of TGF-beta2 in pisces. TGF-beta2 has been cloned from a fish, Cyprinus carpio, by RT-PCR using degenerate oligonucleotide primers. Sequence analysis of the amplified product and alignment of the deduced amino acid sequence with the human TGF-beta2 amino acid sequence revealed 81% and 93% identity in the precursor and the mature regions, respectively. The northern blot analysis of fish heart RNA shows a major messenger RNA species of about 8.0 kb and two messages of very low abundance of about 5.0 kb and 4.0 kb. The identification of TGF-beta2 isoform in Pisces and it's high degree of homology with the mammalian isoform suggests that among all TGF-beta isoforms, TGF-beta2 is the most conserved during evolution.


Assuntos
Carpas/genética , Reação em Cadeia da Polimerase , Fator de Crescimento Transformador beta/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , DNA Complementar/isolamento & purificação , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Fator de Crescimento Transformador beta/isolamento & purificação
15.
Gene ; 263(1-2): 171-8, 2001 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-11223255

RESUMO

Transforming Growth Factor-beta (TGF-beta) and their receptors have been characterized from many organisms. Two TGF-beta signaling receptors called Type I and II have been described for various ligands of the superfamily from organisms ranging from Drosophila to humans. In Xenopus laevis, TGF-beta2 and 5 have been reported and presumably, play important roles during early development. Several Type I and type II receptors for many ligands of the TGF-beta superfamily except TGF-beta type II receptor (TbetaIIR), have been characterized in Xenopus laevis. A chemical cross linking experiment using iodinated TGF-beta1 and -beta5, revealed four specific binding proteins on XTC cells. In order to understand the TGF-beta involvement during Xenopus development, a TGF-beta type II receptor (XTbetaIIR) has been isolated from a XTC cDNA library. XTbetaIIR was a partial cDNA lacking a portion of the signal peptide. The sequence analysis and homology comparison with the human TbetaIIR revealed 67% amino acid similarity in the extra cellular domain, 60% similarity in the transmembrane domain and 87% similarity in the cytoplasmic kinase domain, suggesting that XTbetaIIR is a putative TGF-beta type II receptor. In addition, the consensus amino acid motif for serine threonine receptor kinases was also present. Further, a dominant negative expression construct lacking the cytoplasmic kinase domain (engineered with the signal peptide from human TGF-beta type II receptor), was able to abolish TGF-beta mediated induction of a luciferase reporter plasmid, in a transient cell transfection assay. This substantiates the notion that XTbetaIIR cDNA can act as a receptor for TGF-beta. RT-PCR analysis using RNA isolated from various developmental stages of Xenopus laevis revealed expression of this gene in all the early stages of development and in the adult organs, except in stages 46/48.


Assuntos
DNA Complementar/isolamento & purificação , Receptores de Fatores de Crescimento Transformadores beta/genética , Xenopus laevis/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Reagentes de Ligações Cruzadas , DNA Complementar/química , DNA Complementar/genética , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Luciferases/genética , Luciferases/metabolismo , Dados de Sequência Molecular , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Fator de Crescimento Transformador beta/química , Células Tumorais Cultivadas , Xenopus laevis/embriologia , Xenopus laevis/crescimento & desenvolvimento
16.
Gene ; 189(2): 289-95, 1997 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-9168139

RESUMO

The start sites for the major human TGF-beta 1 transcripts have been reexamined. A comparison of ribonuclease and S1 nuclease protection analyses on native TGF-beta 1 mRNA and in vitro transcribed human TGF-beta 1 transcripts of defined sizes places the most 5' start site for the native TGF-beta 1 message approx. 50 nucleotides upstream from the previously published start site at base +1. Furthermore, the same techniques indicate that the apparent downstream start site at base +271 is an artefact due to the presence of an A + T-rich island in the middle of an otherwise highly G + C-rich sequence. This is not apparent if S1 nuclease protection is used alone, which emphasizes the importance of using the two techniques in combination for this type of analysis. Thus the major 2.5 kb TGF-beta 1 band seen on Northern blots comprises only mRNA transcribed from the more upstream of the two previously characterized promoters. This has important implications both for the transcriptional and translational regulation of this growth factor.


Assuntos
RNA Mensageiro/química , Transcrição Gênica , Fator de Crescimento Transformador beta/genética , Composição de Bases , Neoplasias da Mama/química , Neoplasias da Mama/genética , Humanos , Reação em Cadeia da Polimerase , Sondas RNA , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Ribonucleases/análise , Endonucleases Específicas para DNA e RNA de Cadeia Simples/análise , Células Tumorais Cultivadas
17.
J Mol Endocrinol ; 24(2): 253-60, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10750026

RESUMO

The male accessory sex organs and epididymis regress following androgen depletion, although the onset of apoptosis varies temporally depending upon the tissue type. Transforming growth factor-beta1 (TGF-beta1) is an androgen-repressed gene and believed to be an apoptotic agent in the regressing rat ventral prostate (VP). Hence, in order to investigate the status of TGF-beta isoforms following castration in androgen-dependent tissues other than VP, this study was undertaken. Northern blot analysis using total RNA from these tissues of intact animals showed higher levels of TGF-beta1 expression as compared with VP, indicating a function other than that of an apoptotic agent for this isoform. Following orchiectomy, TGF-beta1 was induced in all organs studied and the levels were highest at day 3 following castration in seminal vesicle (SV) and the epididymis and decreased by day 5 despite the absence of androgens. This observation implies that TGF-beta1 might not be a truly androgen-repressed gene in these tissues. TGF-beta2 was up-regulated in VP, SV, caput and corpus epididymis but was undetectable in the dorsolateral prostate and cauda epididymis. On the other hand, TGF-beta3 expression was refractory to the androgen status in corpus epididymis and SV but was up-regulated in the remaining tissues. The castration-induced induction of mRNAs was attenuated after exogenous androgen administration. Most importantly, all the isoforms differed significantly in the time and magnitude of induction following castration, suggesting that a single hormone, testosterone, modulates the expression of TGF-betas in an isoform- and tissue-specific manner.


Assuntos
Androgênios/fisiologia , Epididimo/fisiologia , Regulação da Expressão Gênica/fisiologia , Próstata/metabolismo , Glândulas Seminais/metabolismo , Testosterona/farmacologia , Fator de Crescimento Transformador beta/genética , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Orquiectomia , Isoformas de Proteínas/genética , Ratos
18.
J Biosci ; 26(1): 39-46, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11255512

RESUMO

The chicken riboflavin carrier protein (RCP) is an estrogen induced egg yolk and white protein. Eggs from hens which have a splice mutation in RCP gene fail to hatch, indicating an absolute requirement of RCP for the transport of riboflavin to the oocyte. In order to understand the mechanism of regulation of this gene by estrogen, the chicken RCP gene including 1 kb of the 5' flanking region has been isolated. Characterization of the gene structure shows that it contains six exons and five introns, including an intron in the 5' untranslated region. Sequence analysis of the 5' flanking region does not show the presence of any classical, palindromic estrogen response element (ERE). However, there are six half site ERE consensus elements. Four deletion constructs of the 5' flanking region with varying number of ERE half sites were made in pGL3 basic vector upstream of the luciferase-coding region. Transient transfection of these RCP promoter deletion constructs into a chicken hepatoma cell line (LMH2A) showed 6-12-fold transcriptional induction by a stable estrogen analogue, moxesterol. This suggests that the RCP gene is induced by estrogen even in the absence of a classical ERE and the half sites of ERE in this promoter may be important for estrogen induction


Assuntos
Proteínas de Transporte/genética , Estrogênios/fisiologia , Regulação da Expressão Gênica/fisiologia , Proteínas de Membrana Transportadoras , Regiões Promotoras Genéticas , Transcrição Gênica/fisiologia , Animais , Sequência de Bases , Galinhas , DNA , Éxons , Íntrons , Dados de Sequência Molecular
19.
Eur J Med Chem ; 54: 605-14, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22748281

RESUMO

A new class of sulfone linked bis heterocycles viz., pyrrolyl/pyrazolyl arylaminosulfonylmethyl 1,3,4-oxadiazoles, 1,3,4-thiadiazoles, and 1,2,4-triazoles were prepared and tested for antimicrobial activity and cytotoxicity. The chloro-substituted compounds 5c, 8c and 14c showed comparable antibacterial activity to chloramphenicol against Pseudomonasaeruginosa and compound 5c exhibited comparable antifungal activity to ketoconazole against Penicilliumchrysogenum. One of the compounds, vinylsulfonyl oxadiazole showed appreciably cytotoxic activity on A549 lung carcinoma cells with an IC(50) at a concentration of 31.7 µM.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/farmacologia , Sulfonas/química , Anti-Infecciosos/química , Anti-Infecciosos/toxicidade , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Técnicas de Química Sintética , Fungos/efeitos dos fármacos , Compostos Heterocíclicos/química , Compostos Heterocíclicos/toxicidade , Humanos
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