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161.
Inhibition of phosphoglucomutase by fructose 2,6-bisphosphate 总被引:1,自引:0,他引:1
Fructose 2,6-bisphosphate inhibits phosphoglucomutase. The inhibition is mixed with respect to glucose 1,6-bisphosphate and non-competitive with respect to glucose 1-phosphate. In contrast with fructose 1,6-bisphosphate and glycerate 1,3-bisphosphate, which also possess inhibitory effect, fructose 2,6-bisphosphate does not phosphorylate phosphoglucomutase. Fructose 2,6-bisphosphate preparations contain contaminants which can explain artefactual results previously reported. 相似文献
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164.
Marta Palomo Manel Vera Susana Martin Sergi Torramad‐Moix Julia Martinez‐Sanchez Ana Belen Moreno Enric Carreras Gins Escolar Aleix Cases Maribel Díaz‐Ricart 《Journal of cellular and molecular medicine》2020,24(2):1713-1723
Endothelial dysfunction is an earlier contributor to the development of atherosclerosis in chronic kidney disease (CKD), in which the role of epigenetic triggers cannot be ruled out. Endothelial protective strategies, such as defibrotide (DF), may be useful in this scenario. We evaluated changes induced by CKD on endothelial cell proteome and explored the effect of DF and the mechanisms involved. Human umbilical cord vein endothelial cells were exposed to sera from healthy donors (n = 20) and patients with end‐stage renal disease on haemodialysis (n = 20). Differential protein expression was investigated by using a proteomic approach, Western blot and immunofluorescence. HDAC1 and HDAC2 overexpression was detected. Increased HDAC1 expression occurred at both cytoplasm and nucleus. These effects were dose‐dependently inhibited by DF. Both the HDACs inhibitor trichostatin A and DF prevented the up‐regulation of the endothelial dysfunction markers induced by the uraemic milieu: intercellular adhesion molecule‐1, surface Toll‐like receptor‐4, von Willebrand Factor and reactive oxygen species. Moreover, DF down‐regulated HDACs expression through the PI3/AKT signalling pathway. HDACs appear as key modulators of the CKD‐induced endothelial dysfunction as specific blockade by trichostatin A or by DF prevents endothelial dysfunction responses to the CKD insult. Moreover, DF exerts its endothelial protective effect by inhibiting HDAC up‐regulation likely through PI3K/AKT. 相似文献
165.
Chaki M Valderrama R Fernández-Ocaña AM Carreras A Gómez-Rodríguez MV López-Jaramillo J Begara-Morales JC Sánchez-Calvo B Luque F Leterrier M Corpas FJ Barroso JB 《Plant, cell & environment》2011,34(11):1803-1818
High temperature (HT) is considered a major abiotic stress that negatively affects both vegetative and reproductive growth. Whereas the metabolism of reactive oxygen species (ROS) is well established under HT, less is known about the metabolism of reactive nitrogen species (RNS). In sunflower (Helianthus annuus L.) seedlings exposed to HT, NO content as well as S-nitrosoglutathione reductase (GSNOR) activity and expression were down-regulated with the simultaneous accumulation of total S-nitrosothiols (SNOs) including S-nitrosoglutathione (GSNO). However, the content of tyrosine nitration (NO(2) -Tyr) studied by high-performance liquid chromatography with tandem mass spectrometry (LC-MS/MS) and by confocal laser scanning microscope was induced. Nitroproteome analysis under HT showed that this stress induced the protein expression of 13 tyrosine-nitrated proteins. Among the induced proteins, ferredoxin-NADP reductase (FNR) was selected to evaluate the effect of nitration on its activity after heat stress and in vitro conditions using 3-morpholinosydnonimine (SIN-1) (peroxynitrite donor) as the nitrating agent, the FNR activity being inhibited. Taken together, these results suggest that HT augments SNOs, which appear to mediate protein tyrosine nitration, inhibiting FNR, which is involved in the photosynthesis process. 相似文献
166.
Carreras C Pascual M Cardona L Marco A Bellido JJ Castillo JJ Tomás J Raga JA Sanfélix M Fernández G Aguilar A 《The Journal of heredity》2011,102(6):666-677
Juvenile loggerhead sea turtles (Caretta caretta) from Atlantic nesting populations migrate into the western Mediterranean, where they share feeding grounds with turtles originating in the Mediterranean. In this scenario, male-mediated gene flow may lead to the homogenization of these distant populations. To test this hypothesis, we genotyped 7 microsatellites from 56 Atlantic individuals sampled from feeding grounds in the western Mediterranean and then compared the observed allele frequencies with published data of 112 individuals from Mediterranean nesting beaches. Mediterranean populations were found to be genetically differentiated from the Atlantic stock reaching the western Mediterranean (F(st) = 0.029, P < 0.001); therefore, the possible mating events between Atlantic and Mediterranean individuals are not sufficient to homogenize these 2 areas. The differentiation observed between these 2 areas demonstrates that microsatellites are sufficiently powerful for mixed stock analysis and that individual assignment (IA) tests can be performed in combination with mitochondrial DNA (mtDNA) analysis. In a set of 197 individuals sampled in western Mediterranean feeding grounds, 87% were robustly assigned to Atlantic or Mediterranean groups with the combined marker, as compared with only 52% with mtDNA alone. These findings provide a new approach for tracking the movements of these oceanic migrants and have strong implications for the conservation of the species. 相似文献
167.
González A Díaz R Díaz M Borrero Y Bruzón RY Carreras B Gato R 《Revista de biología tropical》2011,59(3):1007-1016
Chemical insecticides may be toxic and cause environmental degradation. Consequently, biological control for insects represents an alternative with low ecological impact. In this work, three soil isolates (A21, A51 and C17) from different regions of the Cuban archipelago were identified, characterized and evaluated against Aedes aegypti and Culex quinquefasciatus. The new isolates were compared with reference IPS82 strain and two strains isolated from biolarvicides Bactivec and Bactoculicida, respectively. The differentiation was done by morphological, biochemical, bioassays activity and molecular methods (SDS-PAGE, plasmid profile and random amplified polymorphic analysis). All isolates were identified as Bacillus thuringiensis. The A21, A51 and C17 isolates showed higher larvicide activity than Bactivec's isolated reference strain, against both A. aegypti and C. quinquefasciatus. A21 isolate had a protein profile similar to IPS82 and Bactivec strain. A51 and C17 isolates produced a characteristic proteins pattern. A21 and A51 isolates had plasmid patterns similar to IPS82 standard strain, while C17 isolate had different both plasmid profile and protein bands. All the studied isolates showed a diverse RAPD patterns and were different from the strains previously used in biological control in Cuba. 相似文献
168.
C. Carreras M. Pascual L. Cardona A. Aguilar D. Margaritoulis A. Rees O. Turkozan Y. Levy A. Gasith M. Aureggi M. Khalil 《Conservation Genetics》2007,8(4):761-775
The population genetic structure of the loggerhead sea turtle (Caretta caretta) nesting in the eastern Mediterranean was assessed by sequencing a fragment of the control region of the mitochondrial DNA
(n = 190) and seven microsatellites (n = 112). The two types of markers revealed genetic structuring (mtDNA: γst = 0.212, P < 0.001; nDNA F
st = 0.006, P < 0.001), thus indicating that both females and males are philopatric and that gene flow between populations is restricted.
Mitochondrial DNA data indicate that the female populations nesting on the islands of Crete and Cyprus have suffered a recent
bottleneck or colonization event. However, no bottleneck or founder effect was revealed by nuclear markers, thus indicating
male-mediated gene flow from other populations that would increase nuclear genetic variability. Crete, and to a lower extent
Cyprus, are thought to play a central role in such male-mediated gene flow that may reduce the negative effect of genetic
drift or inbreeding on the small populations of Lebanon and Israel. This population structure indicates that assessing population
relevance only on the basis of genetic variability and size would be misleading, as some populations not fulfilling those
requirements may play a relevant role in genetic exchange and hence contribute to the overall genetic variability. 相似文献
169.
Valderrama R Corpas FJ Carreras A Fernández-Ocaña A Chaki M Luque F Gómez-Rodríguez MV Colmenero-Varea P Del Río LA Barroso JB 《FEBS letters》2007,581(3):453-461
Nitrosative stress has become a usual term in the physiology of nitric oxide in mammalian systems. However, in plants there is much less information on this type of stress. Using olive leaves as experimental model, the effect of salinity on the potential induction of nitrosative stress was studied. The enzymatic l-arginine-dependent production of nitric oxide (NOS activity) was measured by ozone chemiluminiscence. The specific activity of NOS in olive leaves was 0.280nmol NOmg(-1) proteinmin(-1), and was dependent on l-arginine, NADPH and calcium. Salt stress (200mM NaCl) caused an increase of the l-arginine-dependent production of nitric oxide (NO), total S-nitrosothiols (RSNO) and number of proteins that underwent tyrosine nitration. Confocal laser scanning microscopy analysis using either specific fluorescent probes for NO and RSNO or antibodies to S-nitrosoglutathione and 3-nitrotyrosine, showed also a general increase of these reactive nitrogen species (RNS) mainly in the vascular tissue. Taken together, these findings show that in olive leaves salinity induces nitrosative stress, and vascular tissues could play an important role in the redistribution of NO-derived molecules during nitrosative stress. 相似文献
170.
Rosanna Carreras‐De Len Stesha A. Pasachnik Glenn P. Gerber Christopher P. Brooks Ernst Rupp Mark E. Welch 《Ecology and evolution》2019,9(14):8331-8350
Cyclura ricordii is an endemic iguana from Hispaniola Island and is threatened on the IUCN Red List. The main threats are predation by introduced mammals, habitat destruction, and hunting pressure. The present study focused on two nesting sites from Pedernales Province in the Dominican Republic. The hypothesis that natal philopatry influences dispersal and nest‐site selection was tested. Monitoring and sampling took place in 2012 and 2013. Polymorphic markers were used to evaluate whether natal philopatry limits dispersal at multiple spatial scales. Ripley's K revealed that nests were significantly clustered at multiple scales, when both nesting sites were considered and within each nesting site. This suggests a patchy, nonrandom distribution of nests within nest sites. Hierarchical AMOVA revealed that nest‐site aggregations did not explain a significant portion of genetic variation within nesting sites. However, a small but positive correlation between geographic and genetic distance was detected using a Mantel's test. Hence, the relationship between geographic distance and genetic distance among hatchlings within nest sites, while detectable, was not strong enough to have a marked effect on fine‐scale genetic structure. Spatial and genetic data combined determined that the nesting sites included nesting females from multiple locations, and the hypothesis of “natal philopatry” was not supported because females nesting in the same cluster were no more closely related to each other than to other females from the same nesting site. These findings imply that nesting aggregations are more likely associated with cryptic habitat variables contributing to optimal nesting conditions. 相似文献