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141.
Proteomics and transcriptomics investigation on longissimus muscles in Large White and Casertana pig breeds 总被引:1,自引:0,他引:1
Murgiano L D'Alessandro A Egidi MG Crisà A Prosperini G Timperio AM Valentini A Zolla L 《Journal of proteome research》2010,9(12):6450-6466
Consumer complaints against the blandness of modern lean meat and the frequent reference to the more strongly flavored meat that was available years ago have prompted reconsideration of high fat-depositing typical pig breeds. Casertana and Large White pig breeds are characterized by a different tendency toward fat accumulation as they exhibit opposite genetic and physiological traits with respect to the energy metabolism. These physiological differences were investigated in longissimus lumborum muscles through proteomics (2-DE, MS/MS) and microarray approaches. Data were analyzed for pathway and network analyses, as well as GO term enrichment of biological functions. As a result, Casertana showed a greater amount of proteins involved in glycolitic metabolism and mainly rely on fast-mobilizable energy sources. Large White overexpressed cell cycle and skeletal muscle growth related genes. Metabolic behavior and other implications are discussed. 相似文献
142.
Devescovi G Bigirimana J Degrassi G Cabrio L LiPuma JJ Kim J Hwang I Venturi V 《Applied and environmental microbiology》2007,73(15):4950-4958
Burkholderia glumae is an emerging rice pathogen in several areas around the world. Closely related Burkholderia species are important opportunistic human pathogens for specific groups of patients, such as patients with cystic fibrosis and patients with chronic granulomatous disease. Here we report that the first clinical isolate of B. glumae, strain AU6208, has retained its capability to be very pathogenic to rice. As previously reported for rice isolate B. glumae BGR1 (and also for the clinical isolate AU6208), TofI or TofR acyl homoserine lactone (AHL) quorum sensing played a pivotal role in rice virulence. We report that AHL quorum sensing in B. glumae AU6208 regulates secreted LipA lipase and toxoflavin, the phytotoxin produced by B. glumae. B. glumae AU6208 lipA mutants were no longer pathogenic to rice, indicating that the lipase is an important virulence factor. It was also established that type strain B. glumae ATCC 33617 did not produce toxoflavin and lipase and was nonpathogenic to rice. It was determined that in strain ATCC 33617 the LuxR family quorum-sensing sensor/regulator TofR was inactive. Introducing the tofR gene of B. glumae AU6208 in strain ATCC 33617 restored its ability to produce toxoflavin and the LipA lipase. This study extends the role of AHL quorum sensing in rice pathogenicity through the regulation of a lipase which was demonstrated to be a virulence factor. It is the first report of a clinical B. glumae isolate retaining strong rice pathogenicity and finally determined that B. glumae can undergo phenotypic conversion through a spontaneous mutation in the tofR regulator. 相似文献
143.
Repression of interferon regulatory factor 1 by hepatitis C virus core protein results in inhibition of antiviral and immunomodulatory genes 总被引:3,自引:0,他引:3 下载免费PDF全文
144.
Mitochondria are a major source of paraquat-induced reactive oxygen species production in the brain 总被引:1,自引:0,他引:1
Paraquat (PQ(2+)) is a prototypic toxin known to exert injurious effects through oxidative stress and bears a structural similarity to the Parkinson disease toxicant, 1-methyl-4-pheynlpyridinium. The cellular sources of PQ(2+)-induced reactive oxygen species (ROS) production, specifically in neuronal tissue, remain to be identified. The goal of this study was to determine the involvement of brain mitochondria in PQ(2+)-induced ROS production. Highly purified rat brain mitochondria were obtained using a Percoll density gradient method. PQ(2+)-induced hydrogen peroxide (H(2)O(2)) production was measured by fluorometric and polarographic methods. The production of H(2)O(2) was evaluated in the presence of inhibitors and modulators of the mitochondrial respiratory chain. The results presented here suggest that in the rat brain, (a) mitochondria are a principal cellular site of PQ(2+)-induced H(2)O(2) production, (b) PQ(2+)-induced H(2)O(2) production requires the presence of respiratory substrates, (c) complex III of the electron transport chain is centrally involved in H(2)O(2) production by PQ(2+), and (d) the mechanism by which PQ(2+) generates H(2)O(2) depends on the mitochondrial inner transmembrane potential. These observations were further confirmed by measuring PQ(2+)-induced H(2)O(2) production in primary neuronal cells derived from the midbrain. These findings shed light on the mechanism through which mitochondria may contribute to ROS production by other environmental and endogenous redox cycling agents implicated in Parkinson's disease. 相似文献
145.
146.
Immunohistochemical analysis of pRb2/p130, VEGF, EZH2, p53, p16(INK4A), p27(KIP1), p21(WAF1), Ki-67 expression patterns in gastric cancer 总被引:1,自引:0,他引:1
Mattioli E Vogiatzi P Sun A Abbadessa G Angeloni G D'Ugo D Trani D Gaughan JP Vecchio FM Cevenini G Persiani R Giordano A Claudio PP 《Journal of cellular physiology》2007,210(1):183-191
Although the considerable progress against gastric cancer, it remains a complex lethal disease defined by peculiar histological and molecular features. The purpose of the present study was to investigate pRb2/p130, VEGF, EZH2, p53, p16(INK4A), p27(KIP1), p21(WAF1), Ki-67 expressions, and analyze their possible correlations with clinicopathological factors. The expression patterns were examined by immunohistochemistry in 47 patients, 27 evaluated of intestinal-type, and 20 of diffuse-type, with a mean follow up of 56 months and by Western blot in AGS, N87, KATO-III, and YCC-2, -3, -16 gastric cell lines. Overall, stomach cancer showed EZH2 correlated with high levels of p53, Ki-67, and cytoplasmic pRb2/p130 (P < 0.05, and P < 0.01, respectively). Increased expression of EZH2 was found in the intestinal-type and correlated with the risk of distant metastasis (P < 0.05 and P < 0.01, respectively), demonstrating that this protein may have a prognostic value in this type of cancer. Interestingly, a strong inverse correlation was observed between p27(KIP1) expression levels and the risk of advanced disease and metastasis (P < 0.05), and a positive correlation between the expression levels of p21(WAF1) and low-grade (G1) gastric tumors (P < 0.05), confirming the traditionally accepted role for these tumor-suppressor genes in gastric cancer. Finally, a direct correlation was found between the expression levels of nuclear pRb2/p130 and low-grade (G1) gastric tumors that was statistically significant (P < 0.05). Altogether, these data may help shed some additional light on the pathogenetic mechanisms related to the two main gastric cancer histotypes and their invasive potentials. 相似文献
147.
Scala S Ieranò C Ottaiano A Franco R La Mura A Liguori G Mascolo M Staibano S Ascierto PA Botti G De Rosa G Castello G 《Cancer immunology, immunotherapy : CII》2007,56(10):1589-1595
PURPOSE: Although relatively rare, uveal melanoma is the most common ocular tumor of adults. Up to half of uveal melanoma patients die of metastatic disease. CXCR4, a chemokine receptor, is a prognostic factor in cutaneous melanoma involved in angiogenesis and metastasis formation. The aim of this study was to evaluate the expression of CXCR4 in uveal melanoma. METHODS: CXCR4 was detected by immunohistochemistry in 44 samples of uveal melanoma. Staining was categorized into three semiquantitative classes based on the rate of stained (positive) tumor cells: absence of staining, <50% of cell (+) and >50% (++). Correlations between CXCR4 expression, data on patient and tumor features were studied by contingency tables and the chi2 test. Time-to-event curves were studied using the Kaplan-Meier method. Univariate analysis was performed using the log-rank test. Ninety-five percent confidence intervals (95% CI) of hazard ratios were also reported. RESULTS: Staining for CXCR4 protein was absent in 18 tumors (40.9%), present in <50% of cells in 19 (43.2%) and in >50% of cells in 7 (15.9%) tumors. CXCR4 expression correlated to the epithelioid-mixed cell type (P=0.030). No statistically significant relation emerged between CXCR4 expression, largest tumor diameter (LTD) and extracellular matrix patterns as evaluated through histological patterns stained with periodic acid-Schiff (PAS). Events occurred in 2 out of 18 patients (11.1%) with negative tumors (2 deaths), in 3 out of 19 patients (15.8%) with <50% of positive tumor cells (2 deaths and 1 occurrence of metastases) and in 1 out of 7 patients (14.3%) with >50% of positive tumor cells (1 occurrence of metastases). The cell type (P=0.0457) but not CXCR4 showed prognostic value at univariate analysis. CONCLUSION: This study shows that CXCR4 is commonly expressed in uveal melanoma and correlates with cell type a well-established prognostic factor. 相似文献
148.
Lepori MB Lovicu M Dessi V Zappu A Incollu S Zancan L Giacchino R Iorio R Vajro P Maggiore G Marcellini M Barbera C Pellecchia MT Simonetti R Kostic V Farci AM Solinas A De Virgiliis S Cao A Loudianos G 《Genetic testing》2007,11(3):328-332
Herein we report the results of mutation analysis of the ATP7B gene in a group of 134 Wilson disease (WD) families (268 chromosomes) prevalently of Italian origin. Using the SSCP and sequencing methods we identified 71 disease-causing mutations. Twenty-four were novel, while 19 more mutations already described, were identified in new populations in this study. A known mutation G591D showed a regional distribution, since it was only detected in 38.5% of the analyzed chromosomes in WD patients originating from Apulia, a region of South Italy. Detection of new mutations in the ATP7B gene increases our capability of molecular analysis that is essential for early diagnosis and treatment of WD. 相似文献
149.
A ribonuclease III domain protein functions in group II intron splicing in maize chloroplasts 总被引:3,自引:1,他引:2
Watkins KP Kroeger TS Cooke AM Williams-Carrier RE Friso G Belcher SE van Wijk KJ Barkan A 《The Plant cell》2007,19(8):2606-2623
Chloroplast genomes in land plants harbor approximately 20 group II introns. Genetic approaches have identified proteins involved in the splicing of many of these introns, but the proteins identified to date cannot account for the large size of intron ribonucleoprotein complexes and are not sufficient to reconstitute splicing in vitro. Here, we describe an additional protein that promotes chloroplast group II intron splicing in vivo. This protein, RNC1, was identified by mass spectrometry analysis of maize (Zea mays) proteins that coimmunoprecipitate with two previously identified chloroplast splicing factors, CAF1 and CAF2. RNC1 is a plant-specific protein that contains two ribonuclease III (RNase III) domains, the domain that harbors the active site of RNase III and Dicer enzymes. However, several amino acids that are essential for catalysis by RNase III and Dicer are missing from the RNase III domains in RNC1. RNC1 is found in complexes with a subset of chloroplast group II introns that includes but is not limited to CAF1- and CAF2-dependent introns. The splicing of many of the introns with which it associates is disrupted in maize rnc1 insertion mutants, indicating that RNC1 facilitates splicing in vivo. Recombinant RNC1 binds both single-stranded and double-stranded RNA with no discernible sequence specificity and lacks endonuclease activity. These results suggest that RNC1 is recruited to specific introns via protein-protein interactions and that its role in splicing involves RNA binding but not RNA cleavage activity. 相似文献
150.
Isolation, heterologous expression and characterization of an endo-polygalacturonase produced by the phytopathogen Burkholderia cepacia 总被引:1,自引:0,他引:1
Massa C Degrassi G Devescovi G Venturi V Lamba D 《Protein expression and purification》2007,54(2):300-308
Endo-polygalacturonases (endoPGs) belong to the glycoside hydrolase family 28 and hydrolyze the alpha-1,4 glycosidic bond present in the smooth regions of pectins. Pectic substances are among the principal macromolecular components of the primary plant cell walls and are subjected to enzymatic degradation not only in the course of important physiological processes such as plant senescence and ripening, but also during infection events by plant pathogens. Here we report, for the first time, the isolation and the purification of an endoPG (PehA) from the supernatant of the plant pathogen Burkholderia cepacia strain ATCC 25416. In order to obtain adequate amounts of protein required for structural and functional studies, the gene coding for pehA was PCR-amplified and cloned in Escherichia coli cells. The recombinant protein was purified to homogeneity and characterized. PehA exhibited a pI value of 8.0 and an optimal activity at pH 3.5. Far-UV circular dichroism (CD) measurements show that PehA assumes a beta-helix fold super-secondary structural motif. 相似文献