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11.
The expression of the dodecameric ferritin in Listeria spp. is induced by iron limitation and stationary growth phase 总被引:6,自引:0,他引:6
Polidoro M De Biase D Montagnini B Guarrera L Cavallo S Valenti P Stefanini S Chiancone E 《Gene》2002,287(1-2):121-128
The new discipline of Evolutionary Developmental Biology (Evo-Devo) is facing the fascinating paradox of explaining morphological evolution using conserved pieces or genes to build divergent animals. The cephalochordate amphioxus is the closest living relative to the vertebrates, with a simple, chordate body plan, and a genome directly descended from the ancestor prior to the genome-wide duplications that occurred close to the origin of vertebrates. Amphioxus morphology may have remained relatively invariant since the divergence from the vertebrate lineage, but the amphioxus genome has not escaped evolution. We report the isolation of a second Emx gene (AmphiEmxB) arising from an independent duplication in the amphioxus genome. We also argue that a tandem duplication probably occurred in the Posterior part of the Hox cluster in amphioxus, giving rise to AmphiHox14, and discuss the structure of the chordate and vertebrate ancestral clusters. Also, a tandem duplication of Evx in the amphioxus lineage produced a prototypical Evx gene (AmphiEvxA) and a divergent gene (AmphiEvxB), no longer involved in typical Evx functions. These examples of specific gene duplications in amphioxus, and other previously reported duplications summarized here, emphasize the fact that amphioxus is not the ancestor of the vertebrates but 'only' the closest living relative to the ancestor, with a mix of prototypical and amphioxus-specific features in its genome. 相似文献
12.
Fanciulli G Dettori A Tomasi PA Demontis MP Gianorso S Anania V Delitala G 《Life sciences》2002,71(20):2383-2390
Although it has long been known that opioid peptides cause marked changes of pituitary hormone secretion in both animals and humans, little is known about the possible effect(s) of food-derived opioids (exorphins) on pituitary function. In order to investigate the possible role of exorphins derived from wheat gluten on pituitary function, we gave the following treatments to four groups of male rats: intracerebroventricular (ICV) vehicle, Gluten Exorphin B5 (GE-B5) 200 microg ICV, naloxone intraperitoneally (IP) followed by vehicle ICV, naloxone IP followed by GE-B5 ICV. Blood samples for Prolactin (PRL) and Growth Hormone (GH) were taken at intervals for 90 minutes after vehicle or GE-B5 administration. GE-B5 strongly stimulated PRL secretion; its effect was completely abolished by naloxone administration. GH secretion was unaffected by GE-B5 under these experimental conditions. The present study shows for the first time that an opioid peptide derived from wheat gluten, GE-B5, has an effect on pituitary function when administered ICV; its mechanism of action appears to be mediated via classical opioid receptors. 相似文献
13.
Albertini MC Accorsi A Citterio B Burattini S Piacentini MP Uguccioni F Piatti E 《Biochimie》2003,85(10):963-970
The effects of the exposure to a static magnetic field (sMF) of 0.3 +/- 0.03 T on the Fusarium culmorum were investigated in vitro. sMF inhibition of mycelia growth was accompanied by morphological and biochemical changes. Fungal conidia germination and cell viability were also reduced. We provide evidence of the influence of sMF on Ca(2+)-dependent signal transduction pathways involved in conidia germination. Perturbation of these pathways by adding different compounds (i.e. CaCl(2), phorbol 12-myristate 13-acetate, neomycin, EGTA, LiCl) to the medium, suggested that exposed conidia are unable to mobilise calcium from intracellular stores and that the hindered mechanism may be IP(3)-dependent. 相似文献
14.
The N-tosyl carbamates 4a–e, easily prepared starting from the Baylis–Hillman adducts 3a–e, underwent cyclization carried out with I2/NIS in the presence of NaH, to give the corresponding 2-oxo-1,3-oxazolidines 5a–e in good yield and total stereoselection when the substituent at C-5 is Ar. After the removal of tosyl group, followed by
the cleavage of the heterocyclic ring, the α-methyl-α-amino acids 8a,b and 10 were obtained in good yield as hydrochlorides. 相似文献
15.
Coordinating terminal differentiation with permanent exit from the cell cycle is crucial for proper organogenesis, yet how the cell cycle is blocked in differentiated tissues remains unclear. Important roles for retinoblastoma family proteins and Cyclin-dependent kinase inhibitors have been delineated, but in many cases it remains unclear what triggers cell cycle exit. This review focuses on describing recent advances in deciphering how terminal differentiation and exit from the cell cycle are coordinated. 相似文献
16.
Fiorentino A D'Abrosca B Pacifico S Cefarelli G Uzzo P Monaco P 《Bioorganic & medicinal chemistry letters》2007,17(3):636-639
Two new dibenzoxazepinones have been isolated from the leaves of Carex distachya, an herbaceous plant growing in the Mediterranean area. The structures have been elucidated on the basis of their spectroscopic properties. Bidimensional NMR (DQ-COSY, TOCSY, NOESY, ROESY, HSQC, and HMBC) furnished important data useful for the characterization of the molecules. The compounds have been assayed, for the antioxidant activity, by measuring its capacity to scavenge the DPPH, the superoxide anion, and nitric oxide radicals. 相似文献
17.
D'Abrosca B Fiorentino A Pacifico S Cefarelli G Uzzo P Letizia M Monaco P 《Bioorganic & medicinal chemistry letters》2007,17(15):4135-4139
Nine novel natural feruloyl monoglyceride (MGs) macrocycles have been isolated from the leaves of Carex distachya, an herbaceous plant growing in the Mediterranean maquis. All the structures have been elucidated on the basis of their spectroscopic features, especially two-dimensional NMR (DQ-COSY, TOCSY, NOESY, ROESY, HSQC, HMBC, HSQC-TOCSY) and ESI-MS. All the compounds have been assayed as protecting factors against the radical damage of the lipids by using different antioxidant tests. 相似文献
18.
Casado B Iadarola P Pannell LK Luisetti M Corsico A Ansaldo E Ferrarotti I Boschetto P Baraniuk JN 《Journal of proteome research》2007,6(12):4615-4623
The current report describes the use of CapLC-ESI-Q/TOF-MS for investigating the proteome profiles of hypertonic saline-induced sputum samples from 56 smokers. The severity of their lung disease ranged from normal (healthy smokers) to chronic bronchitis, chronic obstructive pulmonary disease (COPD), and COPD with emphysema. This pilot study examined the hypothesis that there were distinct differences in protein expression profiles that were related to the phenotype and cigarette smoking illness severity. A total of 203 unique proteins were identified. These may represent the most highly expressed proteins in induced sputum. Our results provide evidence that different proteins are expressed, as the disease progresses from health to more advanced stages, and support our contention that a proteomic approach would be beneficial in discovering selective molecules linked to specific COPD stages. 相似文献
19.
Piera Cilli Anna Minoprio Cecilia Bossa Margherita Bignami Filomena Mazzei 《The Journal of biological chemistry》2015,290(43):26259-26269
The cellular pool of ribonucleotide triphosphates (rNTPs) is higher than that of deoxyribonucleotide triphosphates. To ensure genome stability, DNA polymerases must discriminate against rNTPs and incorporated ribonucleotides must be removed by ribonucleotide excision repair (RER). We investigated DNA polymerase β (POL β) capacity to incorporate ribonucleotides into trinucleotide repeated DNA sequences and the efficiency of base excision repair (BER) and RER enzymes (OGG1, MUTYH, and RNase H2) when presented with an incorrect sugar and an oxidized base. POL β incorporated rAMP and rCMP opposite 7,8-dihydro-8-oxoguanine (8-oxodG) and extended both mispairs. In addition, POL β was able to insert and elongate an oxidized rGMP when paired with dA. We show that RNase H2 always preserves the capacity to remove a single ribonucleotide when paired to an oxidized base or to incise an oxidized ribonucleotide in a DNA duplex. In contrast, BER activity is affected by the presence of a ribonucleotide opposite an 8-oxodG. In particular, MUTYH activity on 8-oxodG:rA mispairs is fully inhibited, although its binding capacity is retained. This results in the reduction of RNase H2 incision capability of this substrate. Thus complex mispairs formed by an oxidized base and a ribonucleotide can compromise BER and RER in repeated sequences. 相似文献
20.
Giudice EM Grandone A Cirillo G Santoro N Amato A Brienza C Savarese P Marzuillo P Perrone L 《PloS one》2011,6(11):e27933