Expression pattern of claudins 1 and 3-an auxiliary tool in predicting behavior of mucoepidermoid carcinoma of salivary gland origin

Claudins (CLDNs) are a family of membrane proteins important for permeability of tight junctions. They have also been implicated in carcinogenesis and tumor progression. We analyzed patterns of distribution and intensity of expression of CLDNs 1, 3, 4, and 7 in mucoepidermoid carcinoma (MEC) of salivary gland in 39 patients. Correlations between the expression of CLDNs, tumor grade, and survival were explored. In immunohistochemical analysis, high expression of CLDN 1 was seen in low-grade MEC, and it appeared to be a suitable auxiliary marker of good prognosis. It classified MEC similarly to histological grading in 89.7% of cases (p=0.001). High CLDN 3 expression was seen in intermediate-and high-grade MEC, while it was low in low-grade MEC. CLDN 3 intensity correctly categorized tumors into grades in 71.8% of cases (p=0.017). However, in multivariate analysis CLDN 1 and CLDN 3 did not achieve significance over tumor grade in predicting patient behavior. We conclude that analysis of staining intensities of CLDN 1 and 3 is useful as an auxiliary diagnostic and prognostic tool in patients with salivary gland MEC.

Expression of fibroblast growth factor-8 and regulation of cognate receptors, fibroblast growth factor receptor-3c and-4, in bovine antral follicles

Paracrine cell signaling is believed to be important for ovarian follicle development, and a role for some members of the fibroblast growth factor (FGF) family has been suggested. In the present study, we tested the hypothesis that FGF-8 and its cognate receptors (FGFR3c and FGFR4) are expressed in bovine antral follicles. RT-PCR was used to analyze bovine Fgf8, Fgfr3c and Fgfr4 mRNA levels in oocytes, and granulosa and theca cells. Fgf8 expression was detected in oocytes and in granulosa and theca cells; this expression pattern differs from that reported in rodents. Granulosa and theca cells, but not oocytes, expressed Fgfr3c, and expression in granulosa cells increased significantly with follicle estradiol content, a major indicator of follicle health. Fgfr4 expression was restricted to theca cells in the follicle, and decreased significantly with increasing follicle size. To investigate the potential regulation of Fgfr3c expression in the bovine granulosa, cells were cultured in serum-free medium with FSH or IGF-I; gene expression was upregulated by FSH but not by IGF-I. The FSH-responsive and developmentally regulated patterns of Fgfr3c mRNA expression suggest that this receptor is a potential mediator of paracrine signaling to granulosa cells during antral follicle growth in cattle.

Expression and variability of molecular chaperones in the sugarcane expressome

Molecular chaperones perform folding assistance in newly synthesized polypeptides preventing aggregation processes, recovering proteins from aggregates, among other important cellular functions. Thus their study presents great biotechnological importance. The present work discusses the mining for chaperone-related sequences within the sugarcane EST genome project database, which resulted in approximately 300 different sequences. Since molecular chaperones are highly conserved in most organisms studied so far, the number of sequences related to these proteins in sugarcane was very similar to the number found in the Arabidopsis thaliana genome. The Hsp70 family was the main molecular chaperone system present in the sugarcane expressome. However, many other relevant molecular chaperones systems were also present. A digital RNA blot analysis showed that 5'ESTs from all molecular chaperones were found in every sugarcane library, despite their heterogeneous expression profiles. The results presented here suggest the importance of molecular chaperones to polypeptide metabolism in sugarcane cells, based on their abundance and variability. Finally, these data have being used to guide more in deep analysis, permitting the choice of specific targets to study. (c) 2006 Elsevier GmbH. All rights reserved.

A Family of Autoconnected Transformers for 12-and 18-Pulse Converters-Generalization for Delta and Wye Topologies

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cloning, expression, purification and characterization of recombinant glutathione-S-transferase from Xylella fastidiosa

Xylella fastidiosa is an important pathogen bacterium transmitted by xylem-feedings leafhoppers that colonizes the xylem of plants and causes diseases on several important crops including citrus variegated chlorosis (CVC) in orange and lime trees. Glutathione-S-transferases (GST) form a group of multifunctional isoenzymes that catalyzes both glutathione (GSH)-dependent conjugation and reduction reactions involved in the cellular detoxification of xenobiotic and endobiotic compounds. GSTs are the major detoxification enzymes found in the intracellular space and mainly in the cytosol from prokaryotes to mammals, and may be involved in the regulation of stress-activated signals by suppressing apoptosis signal-regulating kinase 1. In this study, we describe the cloning of the glutathione-S-transferase from X. fastidiosa into pET-28a(+) vector, its expression in Escherichia coli, purification and initial structural characterization. The purification of recombinant xfGST (rxfGST) to near homogeneity was achieved using affinity chromatography and size-exclusion chromatography (SEC). SEC demonstrated that rxfGST is a homodimer in solution. The secondary and tertiary structures of recombinant protein were analyzed by circular dichroism and fluorescence spectroscopy, respectively. The enzyme was assayed for activity and the results taken together indicated that rxfGST is a stable molecule, correctly folded, and highly active. Several members of the GST family have been extensively studied. However, xfGST is part of a less-studied subfamily which yet has not been structurally and biochemically characterized. In addition, these studies should provide a useful basis for future studies and biotechnological approaches of rxfGST. (C) 2008 Elsevier B.V. All rights reserved.

The plant energy-dissipating mitochondrial systems: Depicting the genomic structure and the expression profiles of the gene families of uncoupling protein and alternative oxidase in monocots and dicots

The simultaneous existence of alternative oxidases and uncoupling proteins in plants has raised the question as to why plants need two energy-dissipating systems with apparently similar physiological functions. A probably complete plant uncoupling protein gene family is described and the expression profiles of this family compared with the multigene family of alternative oxidases in Arabidopsis thaliana and sugarcane (Saccharum sp.) employed as dicot and monocot models, respectively. In total, six uncoupling protein genes, AtPUMP1-6, were recognized within the Arabidopsis genome and five (SsPUMP1-5) in a sugarcane EST database. The recombinant AtPUMP5 protein displayed similar biochemical properties as AtPUMP1. Sugarcane possessed four Arabidopsis AOx1-type orthologues (SsAOx1a-1d); no sugarcane orthologue corresponding to Arabidopsis AOx2-type genes was identified. Phylogenetic and expression analyses suggested that AtAOx1d does not belong to the AOx1-type family but forms a new (AOx3-type) family. Tissue-enriched expression profiling revealed that uncoupling protein genes were expressed more ubiquitously than the alternative oxidase genes. Distinct expression patterns among gene family members were observed between monocots and dicots and during chilling stress. These findings suggest that the members of each energy-dissipating system are subject to different cell or tissue/organ transcriptional regulation. As a result, plants may respond more flexibly to adverse biotic and abiotic conditions, in which oxidative stress is involved. © The Author [2006]. Published by Oxford University Press [on behalf of the Society for Experimental Biology]. All rights reserved.

Development and Biotechnological Application of a Novel Endoxylanase Family GH10 Identified from Sugarcane Soil Metagenome

Metagenomics has been widely employed for discovery of new enzymes and pathways to conversion of lignocellulosic biomass to fuels and chemicals. In this context, the present study reports the isolation, recombinant expression, biochemical and structural characterization of a novel endoxylanase family GH10 (SCXyl) identified from sugarcane soil metagenome. The recombinant SCXyl was highly active against xylan from beechwood and showed optimal enzyme activity at pH 6,0 and 45°C. The crystal structure was solved at 2.75 Å resolution, revealing the classical (β/α)8-barrel fold with a conserved active-site pocket and an inherent flexibility of the Trp281-Arg291 loop that can adopt distinct conformational states depending on substrate binding. The capillary electrophoresis analysis of degradation products evidenced that the enzyme displays unusual capacity to degrade small xylooligosaccharides, such as xylotriose, which is consistent to the hydrophobic contacts at the +1 subsite and low-binding energies of subsites that are distant from the site of hydrolysis. The main reaction products from xylan polymers and phosphoric acid-pretreated sugarcane bagasse (PASB) were xylooligosaccharides, but, after a longer incubation time, xylobiose and xylose were also formed. Moreover, the use of SCXyl as pre-treatment step of PASB, prior to the addition of commercial cellulolytic cocktail, significantly enhanced the saccharification process. All these characteristics demonstrate the advantageous application of this enzyme in several biotechnological processes in food and feed industry and also in the enzymatic pretreatment of biomass for feedstock and ethanol production. © 2013 Alvarez et al.

Expression, purification and molecular analysis of the human ZNF706 protein

Background: The ZNF706 gene encodes a protein that belongs to the zinc finger family of proteins and was found to be highly expressed in laryngeal cancer, making the structure and function of ZNF706 worthy of investigation. In this study, we expressed and purified recombinant human ZNF706 that was suitable for structural analysis in Escherichia coli BL21(DH3). Findings. ZNF706 mRNA was extracted from a larynx tissue sample, and cDNA was ligated into a cloning vector using the TOPO method. ZNF706 protein was expressed according to the E. coli expression system procedures and was purified using a nickel-affinity column. The structural qualities of recombinant ZNF706 and quantification alpha, beta sheet, and other structures were obtained by spectroscopy of circular dichroism. ZNF706's structural modeling showed that it is composed of α-helices (28.3%), β-strands (19.4%), and turns (20.9%), in agreement with the spectral data from the dichroism analysis. Conclusions: We used circular dichroism and molecular modeling to examine the structure of ZNF706. The results suggest that human recombinant ZNF706 keeps its secondary structures and is appropriate for functional and structural studies. The method of expressing ZNF706 protein used in this study can be used to direct various functional and structural studies that will contribute to the understanding of its function as well as its relationship with other biological molecules and its putative role in carcinogenesis. © 2013 Colombo et al.; licensee BioMed Central Ltd.

Ki-67 and CD100 immunohistochemical expression is associated with local recurrence and poor prognosis in soft tissue sarcomas, respectively

Soft tissue sarcomas (STSs) are a heterogeneous group of mesenchymal tumors of >50 subtypes. However, STSs represent <1% of types of cancer. Despite this low frequency, the disease is aggressive and treatment, when possible, is based on traditional chemotherapies. A number of cases of resistance to adjuvant therapies have been reported. Metastases are commonly identified in STS patients during diagnosis and the development of effective clinical parameters is crucial for correct management of the disease. The use of biological markers in cancer is a useful tool to determine patient prognosis. Ki--67 is a protein marker for proliferation of somatic cells and is widely used in prognostic studies of various types of tumor, including STSs. Cluster of differentiation 100 (CD100) is a member of the semaphorin family. The family was initially described as axon guidance molecules important for angiogenesis, organogenesis, apoptosis and neoplasia. CD100 was previously utilized as a prognostic factor in tumors and also in STSs. In the present study, protein expression of Ki--67 and CD100 was analyzed by immunohistochemistry in samples of STS patients of the Barretos Cancer Hospital (Barretos, Brazil) to establish prognostic criteria of the disease. Results demonstrate a correlation between CD100 expression and poor prognosis, consistent with a previous study. Moreover, the expression of Ki-67 was identified to correlate with presence of local or locoregional recurrence. To the best of our knowledge, no large casuistic study has revealed this correlation between Ki--67 and local recurrence in STSs. The use of Ki--67 and CD100 as markers in clinical pathological analysis may be suitable as a prognostic criterion in disease progression.

Transcription Factor CREB3L1 Regulates Vasopressin Gene Expression in the Rat Hypothalamus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Involvement of Renal Corpuscle microRNA Expression on Epithelial-to-Mesenchymal Transition in Maternal Low Protein Diet in Adult Programmed Rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Exercise training decreases mitogen-activated protein kinase phosphatase-3 expression and suppresses hepatic gluconeogenesis in obese mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Manipulation of the periovulatory sex steroidal milieu affects endometrial but not luteal gene expression in early diestrus Nelore cows

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cell cycle kinetics, apoptosis rates, DNA damage and TP53 gene expression in bladder cancer cells treated with allyl isothiocyanate (mustard essential oil)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Transcriptional Activity, Chromosomal Distribution and Expression Effects of Transposable Elements in Coffea Genomes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)