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61.
Chiara Sandri Francesca Caccavari Donatella Valdembri Chiara Camillo Stefan Veltel Martina Santambrogio Letizia Lanzetti Federico Bussolino Johanna Ivaska Guido Serini 《Cell research》2012,22(10):1479-1501
During developmental and tumor angiogenesis, semaphorins regulate blood vessel navigation by signaling through plexin receptors that inhibit the R-Ras subfamily of small GTPases. R-Ras is mainly expressed in vascular cells, where it induces adhesion to the extracellular matrix (ECM) through unknown mechanisms. We identify the Ras and Rab5 interacting protein RIN2 as a key effector that in endothelial cells interacts with and mediates the pro-adhesive and -angiogenic activity of R-Ras. Both R-Ras-GTP and RIN2 localize at nascent ECM adhesion sites associated with lamellipodia. Upon binding, GTP-loaded R-Ras converts RIN2 from a Rab5 guanine nucleotide exchange factor (GEF) to an adaptor that first interacts at high affinity with Rab5-GTP to promote the selective endocytosis of ligand-bound/active β1 integrins and then causes the translocation of R-Ras to early endosomes. Here, the R-Ras/RIN2/Rab5 signaling module activates Rac1-dependent cell adhesion via TIAM1, a Rac GEF that localizes on early endosomes and is stimulated by the interaction with both Ras proteins and the vesicular lipid phosphatidylinositol 3-monophosphate. In conclusion, the ability of R-Ras-GTP to convert RIN2 from a GEF to an adaptor that preferentially binds Rab5-GTP allows the triggering of the endocytosis of ECM-bound/active β1 integrins and the ensuing funneling of R-Ras-GTP toward early endosomes to elicit the pro-adhesive and TIAM1-mediated activation of Rac1. 相似文献
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Camillo De Camillis Jean-Christophe Bligny David Pennington Balázs Pályi 《The International Journal of Life Cycle Assessment》2012,17(4):511-515
Purpose
This paper illustrates the consensus achieved by the members of the European Food Sustainable Consumption and Production Round Table Working Group 1 in their second scientific workshop held in the European Commission’s Joint Research Centre site in Ispra, Italy on July 5–7, 2011. This workshop came after having run a detailed analysis, of data gaps and of methodologies, for the environmental assessment of food and drink products. In particular, the aim of this workshop was to reach consensus amongst key stakeholders on those approaches found diverging across methodologies and on which the forthcoming protocol for the ENVIronmental assessment of FOOds and Drinks (ENVIFOOD Protocol) is expected to provide guidance to the sector. 相似文献66.
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Immune-mediated beta-cell destruction in vitro and in vivo-A pivotal role for galectin-3 总被引:2,自引:0,他引:2
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Jan E. Backhausen Susanne Vetter Elisabeth Baalmann Camillo Kitzmann Renate Scheibe 《Planta》1998,205(3):359-366
Chloroplasts isolated from spinach (Spinacia oleracea L.) leaves and green sweet-pepper (Capsicum annuum L. var. grossum (L.) Sendt.) fruits contain NADP-dependent malate dehydrogenase (MDH; EC 1.1.1.82) and the bispecific NAD(P)-glyceraldehyde 3-phosphate
dehydrogenase (GAPDH; EC 1.2.1.13). The NADP-dependent MDH and GAPDH are activated in the light, and inactive in the dark.
We found that chloroplasts possess additional NAD-dependent MDH activity which is, like the NAD-dependent GAPDH activity,
not influenced by light. In heterotrophic chromoplasts from red sweet-pepper fruits, the NADP-dependent MDH and the NAD(P)-GAPDH
isoenzymes disappear during the developmental transition and only NAD-specific isoforms are found. Spinach chloroplasts contain
both NAD/H and NADP/H at significant concentrations. Measurements of the pyridine dinucleotide redox states, performed under
dark and various light conditions, indicate that NAD(H) is not involved in electron flow in the light. To analyze the contribution
of NAD(H)-dependent reactions during dark metabolism, plastids from spinach leaves or green and red sweet-pepper fruits were
incubated with dihydroxyacetone phosphate (DHAP). Exogenously added DHAP was oxidized into 3-phosphoglycerate by all types
of plastids only in the presence of oxaloacetate, but not with nitrite or in the absence of added electron acceptors. We conclude
that the NAD-dependent activity of GAPDH is essential in the dark to produce the ATP required for starch metabolism; excess
electrons produced during triose-phosphate oxidation can selectively be used by NAD-MDH to form malate. Thus NADPH produced
independently in the oxidative pentose-phosphate pathway will remain available for reductive processes inside the plastids.
Received: 2 July 1997 / Accepted: 20 October 1997 相似文献
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