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81.
Nicolini C Spera R Stura E Fiordoro S Giacomelli L 《Journal of cellular biochemistry》2006,97(5):1151-1159
Human lymphocytes gene expression before and after PHA stimulation is monitored by DNASER technology, a novel bioinstrumentation entirely constructed in our laboratories as previously reported. The validity of the DNASER measurements is confirmed by standard fluorescence microscopy equipped with CCD. The human lymphocytes gene expression here experimentally probed using commercially available DNA microarrays such as Human Starter, appears compatible both with independent bioinformatic prediction and with existing experimental data, pointing to MYC as the key gene in the G0-G1 transition induced by PHA in resting lymphocytes. It does not escape our notice that in cell biology and cancer research DNASER technology based on microarray constructed with few leader genes identified from bioinformatics represents a meaningful cost-effective route alternative to massive frequently misleading molecular genomics. 相似文献
82.
83.
Resta N Susca FC Di Giacomo MC Stella A Bukvic N Bagnulo R Simone C Guanti G 《Journal of cellular physiology》2006,209(1):67-73
Roberts syndrome (RS) is a rare disorder characterized by tetraphocomelia and several other clinical features. Cells from RS patients exhibit characteristic premature separation of heterochromatic region of many chromosomes and abnormalities in cell cycle. Mutations in the ESCO2 gene have recently been identified in 20 RS families. We performed mutational analysis of the ESCO2 gene in two fetuses diagnosed with RS and their normal parents. In both fetuses, we identified homozygosity for the c. 745_746delGT mutation, while the non-consanguineous parents were both heterozygous for the same mutation. Considering the position of the mutation identified, we carried out qualitative and quantitative real-time ESCO2 cDNA analysis on RNA isolated from CVS-stromal cells in one fetus, amniocytes in the second fetus, and lymphocytes from the heterozygous parents. The results of this analysis showed that despite the presence of a premature termination codon (PTC) 112 nucleotides upstream of the next exon3-exon4 junction, the mutant ESCO2 mRNA was present in both fetuses, albeit at low levels, indicating a partial resistance to nonsense mediated decay (NMD). Interestingly, when cells derived from the two fetuses were treated with an inhibitor of translation, they revealed the presence of tissue and individual variability in NMD efficiency, despite the identical mutational status. The existence of such a variation in the NMD efficiency could explain the broad intrafamilial and interfamilial variability in the clinical presentation of RS patients, and in other genetic diseases where nonsense mutations are responsible for most of the mutation load. Moreover, considering that a mutated full length mRNA was produced in both fetuses, we used Western blot analysis to demonstrate the absence of the ESCO2-truncated protein in cells derived from both fetuses and in a lymphoblastoid cell line derived from the parents. 相似文献
84.
La Rosa G Muscillo M Sali M De Carolis E Marianelli C Ciuchini F Fasanella A Adone R 《The new microbiologica》2006,29(4):307-310
This study investigated the genetic bases of attenuation in the Bacillus anthracis vaccine strain "Carbosap" used in Italy against anthrax in cattle and sheep. Twelve genes involved in virulence regulatory pathways underwent sequence analysis in comparison with a B. anthracis virulent strain. 相似文献
85.
Marianelli C Ciuchini F Tarantino M Pasquali P Adone R 《Microbes and infection / Institut Pasteur》2006,8(3):860-865
The rpoB gene encoding the beta subunit of the DNA-dependent RNA polymerase was molecularly characterized by PCR amplification and DNA sequencing in 26 Brucella reference strains by using primers selected according to the B. melitensis 16 M rpoB published sequence. Comparison of the rpoB nucleotide sequence of all Brucella strains analysed revealed specific nucleotide variations associated with different Brucella species and biovars. 17 rpoB alleles were recognized and new Brucella typing is proposed. Our results suggest that the rpoB gene polymorphism can be used to identify all Brucella species and most of the biovars, offering an improvement over conventional typing methods. 相似文献
86.
Papa R Glagla S Danchin A Schweder T Marino G Duilio A 《Extremophiles : life under extreme conditions》2006,10(6):483-491
The capability of microorganisms to utilize different carbohydrates as energy source reflects the availability of these substrates in their habitat. Investigation of the proteins involved in carbohydrate usage, in parallel with analysis of their expression, is then likely to provide information on the interaction between microorganisms and their ecosystem. We analysed the growth behaviour of the marine Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 in the presence and in the absence of different carbon source. A marked increase in the optical density was detected when l-malate was added to the growth medium. Bacterial proteins differently expressed in the presence of l-malate were identified by proteomic profiling experiments. On the basis of their relative increase, six proteins were selected for further analyses. Among these, the expression of a putative outer membrane porin was demonstrated to be heavily induced by l-malate. The presence of a functionally active two-component regulatory system very likely controlled by l-malate was found in the upstream region of the porin gene. A non functional genomic porin mutant was then constructed showing a direct involvement of the protein in the uptake of l-malate. To the best of our knowledge, the occurrence of such a regulatory system has never been reported in Pseudoalteromonads so far and might constitute a key step in the development of an effective inducible cold expression system. 相似文献
87.
Occurrence of A-kinase anchor protein and associated cAMP-dependent protein kinase in the inner compartment of mammalian mitochondria 总被引:1,自引:0,他引:1
Sardanelli AM Signorile A Nuzzi R Rasmo DD Technikova-Dobrova Z Drahota Z Occhiello A Pica A Papa S 《FEBS letters》2006,580(24):5690-5696
Evidence showing the existence in the inner compartment of rat-heart mitochondria of AKAP121 and associated PKA is presented. Immunoblotting analysis and trypsin digestion pattern show that 90% or more of mitochondrial C-PKA, R-PKA and AKAP121 is localized in the inner mitochondrial compartment, when prepared both from isolated mitochondria or cardiomyocyte cultures. This localization is verified by measurement of the specific catalytic activity of PKA, radiolabelling of R-PKA by (32)P-phosphorylated C-PKA and of AKAP by (32)P-phosphorylated R-PKA and electron microscopy of mitochondria exposed to gold-conjugated AKAP121 antibody. 相似文献
88.
89.
Phospholipase D (PLD) hydrolyzes the phosphodiester bond of the predominant membrane phospholipid, phosphatidylcholine producing phosphatidic acid and free choline. This activity can participate in signal transduction pathways and impact on vesicle trafficking for secretion and endocytosis, as well as receptor signalling. Phospholipids can regulate PLD activity directly, through specific intermolecular interactions, or indirectly, through their effect on the localization or activity of PLD's protein effectors. This short review highlights these various phospholipid inputs into the regulation of PLD activity and also reviews potential roles for PLD-generated phosphatidic acid, particularly a mechanism by which the phospholipid may participate in the process of vesicular trafficking. 相似文献
90.
Rosanna Malbran Forteza S. Marina Casalino-Matsuda Nieves S. Falcon Monica Valencia Gattas Maria E. Monzon 《The Journal of biological chemistry》2012,287(50):42288-42298
Cigarette smoke (CigS) exposure is associated with increased bronchial epithelial permeability and impaired barrier function. Primary cultures of normal human bronchial epithelial cells exposed to CigS exhibit decreased E-cadherin expression and reduced transepithelial electrical resistance. These effects were mediated by hyaluronan (HA) because inhibition of its synthesis with 4-methylumbelliferone prevented these effects, and exposure to HA fragments of <70 kDa mimicked these effects. We show that the HA receptor layilin is expressed apically in human airway epithelium and that cells infected with lentivirus expressing layilin siRNAs were protected against increased permeability triggered by both CigS and HA. We identified RhoA/Rho-associated protein kinase (ROCK) as the signaling effectors downstream layilin. We conclude that HA fragments generated by CigS bind to layilin and signal through Rho/ROCK to inhibit the E-cadherin gene and protein expression, leading to a loss of epithelial cell-cell contact. These studies suggest that HA functions as a master switch protecting or disrupting the epithelial barrier in its high versus low molecular weight form and that its depolymerization is a first and necessary step triggering the inflammatory response to CigS. 相似文献