1,721,000 research outputs found
Farmaci e droghe nei depuratori varesini: un anno di monitoraggio
No full textLa presentazione ha avuto lo scopo di illustrare i risultati di un anno di monitoraggio di farmaci e droghe nei depuratori varesini. Questa ricerca si è inserita all'interno di un progetto dal titolo: "Emergenza farmaci nelle acque - monitoraggio e studio di processi di trattamento", finanziato dalla Fondazione Comunitaria del Varesotto ONLUS
Somatic embryogenesis in vitis vinifera: A proteomic approach
No full textIn this study, we have identified a number of proteins involved in different pathways during early embryo induction. Proteins were extracted from embryogenic and non-embryogenic calli of Vitis vinifera grown on a 2,4-D containing media. The protein extracts were separated by two dimensional gel electrophoresis and identified by mass spectrometry. Some of the differentially expressed proteins identified may be involved in detoxification or in the maintenance of redox state. This suggests that an oxidative burst occurs during the development of somatic embryos and might lead to programmed cell death (PCD) of certain cells. Glutathione-S-transferase (GST) and cytosolic ascorbate peroxidase during acquisition of embryogenic potential are likely to be involved in protecting cells against the harmful effects of reactive oxygen species (ROS); however, the redox status of cells and the glutathione content may have important roles in developmental processes, especially in triggering cell division. In fact, it has recently been proposed that GST may serve as carrier for plant hormones, including auxin. A proteasome subunit was also identified. It is known that protea-some activity is closely aligned with cell proliferation processes; moreover, knockout mutants of Physcomitrella patens show developmental defects partially reversed by auxin and cytokinin, suggesting that the responses to these hormones may require degradation of short-lived regulators by the proteasome. An intriguing possibility is that this regulator acts as a repressor, preventing development in the absence of appropriate hormonal signals. When a sufficient concentration of hormone is reached, these repressors are removed by degradation. NDPK was differentially expressed; its role remains to be elucidated in somatic embryogenesis but the literature suggests a possible function in the regulation of cell morphogenesis. These proteins are candidates for further investigation in term of functional relevance for somatic embryo-genesis
Proteomic analysis of somatic embryogenesis in Vitis vinifera
No full textTwo dimensional gel electrophoresis coupled to mass spectrometry has been used to study the somatic embryogenesis in Vitis vinifera, by comparing embryogenic and non embryogenic calluses of the Thompson seedless cv. More than 1,000 spots were reproducibly resolved in colloidal Coomassie brilliant blue stained gels over a pI nonlinear range of 3-10 in the first dimension and using homogeneous 12.5% polyacrylamide gels in the second dimension. The expression pattern of 35 spots differed significantly between the two samples. These spots were processed by mass spectrometry analysis and the protein identity was assigned by using both the non-redundant protein and EST databases. Several responsive proteins, some already known to be involved in the somatic embryogenesis process while others, for the first time put into relation with this process, have been described. Moreover, they have been subdivided in functional categories, and their putative role is discussed in terms of their relevance in the somatic embryogenesis process
Effects of a complex mixture of therapeutic drugs on unicellular algae Pseudokirchneriella subcapitata.
No full textPharmaceutically-active compounds are regularly and widely released into the aquatic environment in an unaltered form or as metabolites. So far, little is known about their potential detrimental effects on algae populations which can ultimately impact nutrient cycling and oxygen balance. For our analysis, the common microalga Pseudokirchneriella subcapitata (P. subcapitata) was exposed to a mixture of 13 drugs found in Italian wastewaters and rivers. Traces of pharmaceuticals investigated were detected in
treated algal cells, except for cyclophosphamide and ranitidine, indicating that these algae are able to absorb pharmaceutical pollutants from the environment. The effects of the treatment were investigated AFLP assessment of DNA damage and 2-DE proteomic analysis. While no genotoxic effect was detected, proteomic analysis showed that algae are sensitive to
the presence of drugs and that, in particular, the chloroplast is affected
Seagrass light acclimation: 2-DE protein analysis in Posidonia leaves grown in chronic low light conditions
No full textPosidonia oceanica meadows are among the most valuable coastal systems in the Mediterranean basin. They
provide nursery and forage areas for many commercially important species, including juvenile mollusc,
finfish, and crustaceans. In the Mediterranean Sea, P. oceanica beds have recently suffered from progressive
die-offs attributed to lower light availability from elevated water turbidity. In order to understand adaptive
low-light responses of this seagrass, we compared the protein expression in plants collected from turbid
waters (low-light) with plants collected from pristine-clear waters (high-light). More than 2600 proteins
were detected in leaves from both sites. Among them, 26 proteins were differentially expressed in low-light
conditions, 12 of which were identified through MASCOT analyses. The remaining 14 proteins, did not receive
significant identity scores due to a lack of genomic and proteomic information in available databases.
Nevertheless, we observed a 30% down-regulation of RuBisCo large subunit in low-light acclimated leaves.
Whereas, enzymes involved in carbohydrate cleavage (1-fructose-bisphosphate aldolase, nucleoside
diphosphate kinase, and beta-amylase) were upregulated in low-light conditions. Electron microscopy
studies also revealed substantial changes in the stroma lamellae/grana ratios in chloroplasts receiving lowlight,
possibly as a mechanism for re-establishing optimal PSI/PSII ratios. Furthermore, under low-light
conditions, four components of the ubiquitin/mediated proteolysis pathway (26 S proteasome regulatory,
proteasome beta type 1, proteasome 7 D beta type, and proteasome alpha 7), and the perchloric acid soluble
translation inhibitor protein, were upregulated. This suggests that, in P. oceanica leaves, enhanced protein
turnover mediates acclimation to low-light conditions. Also, enzymes involved in defending against cellular
stress (superoxide dismutase, pyridoxine, and 2-caffeic-acido-methyl transferase) were differentially
expressed in low-light regime. Subsequent aquaria studies involving P. oceanica transplants maintained in
low- and high-light conditions, also demonstrate RuBisCo down-regulation and proteasomes upregulation in
low-light acclimated plants
How to kill two birds with one stone: activation of the mybleu-regulated pathway allows rice to tolerate and escape anoxia
No full text2-DE polypeptide mapping of Posidonia oceanica Leaf, a molecular tool for marine environment analyses.
No full textThe aim of this research is to provide a molecular tool based on polypeptide mapping to investigate the flowering marine plant Posidonia oceanica. This plant is very vulnerable to contaminants; thus it is considered a valuable bio-indicator of water quality in bio-monitoring of coastal environments. Posidonia oceanica was found to be recalcitrant to the common protein extraction methods. In the present work, three different extraction procedures were compared to obtain high yield and quality protein extracts suitable for mono-dimensional and bi-dimensional electrophoresis (1-DE and 2-DE). Proteins were extracted from juvenile, intermediate and adult leaves in order to assess the influence of tissue differentiation on protein yield. The highest protein yield was obtained with 20% trichloroacetic acid (TCA) precipitation of proteins. The best extraction efficiency was found in juvenile leaves as compared with intermediate and adult ones. However, as a large amount of juvenile leaves is required for obtaining sufficiently large protein samples, these were considered not suitable for the electrophoretic analysis. Extensive sampling could introduce further damage in the meadows under study. High quality 2-DE polypeptide mappings were obtained only from intermediate and adult leaves; the good reproducibility of protein patterns indicates that this approach could be used to explore changes in protein expression of P. oceanica in response to altered environmental conditions. © 2008 Società Botanica Italiana
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