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81.
Susana González-Pérez Ana Garcés-Claver Cristina Mallor Luis E. Sáenz de Miera Oreto Fayos Federico Pomar Fuencisla Merino Cristina Silvar 《PloS one》2014,9(12)
The successful exploitation of germplasm banks, harbouring plant genetic resources indispensable for plant breeding, will depend on our ability to characterize their genetic diversity. The Vegetable Germplasm Bank of Zaragoza (BGHZ) (Spain) holds an important Capsicum annuum collection, where most of the Spanish pepper variability is represented, as well as several accessions of other domesticated and non-domesticated Capsicum spp from all over the five continents. In the present work, a total of 51 C. annuum landraces (mainly from Spain) and 51 accessions from nine Capsicum species maintained at the BGHZ were evaluated using 39 microsatellite (SSR) markers spanning the whole genome. The 39 polymorphic markers allowed the detection of 381 alleles, with an average of 9.8 alleles per locus. A sizeable proportion of alleles (41.2%) were recorded as specific alleles and the majority of these were present at very low frequencies (rare alleles). Multivariate and model-based analyses partitioned the collection in seven clusters comprising the ten different Capsicum spp analysed: C. annuum, C. chinense, C. frutescens, C. pubescens, C. bacatum, C. chacoense and C. eximium. The data clearly showed the close relationships between C. chinense and C. frutescens. C. cardenasii and C. eximium were indistinguishable as a single, morphologically variable species. Moreover, C. chacoense was placed between C. baccatum and C. pubescens complexes. The C. annuum group was structured into three main clusters, mostly according to the pepper fruit shape, size and potential pungency. Results suggest that the diversification of C. annuum in Spain may occur from a rather limited gene pool, still represented by few landraces with ancestral traits. This ancient population would suffer from local selection at the distinct geographical regions of Spain, giving way to pungent and elongated fruited peppers in the South and Center, while sweet blocky and triangular types in Northern Spain. 相似文献
82.
Federico Machinandiarena Leandro Nakamatsu Gustavo E. Schujman Diego de Mendoza Daniela Albanesi 《Molecular microbiology》2020,114(4):653-663
A key aspect in membrane biogenesis is the coordination of fatty acid to phospholipid synthesis rates. In most bacteria, PlsX is the first enzyme of the phosphatidic acid synthesis pathway, the common precursor of all phospholipids. Previously, we proposed that PlsX is a key regulatory point that synchronizes the fatty acid synthase II with phospholipid synthesis in Bacillus subtilis. However, understanding the basis of such coordination mechanism remained a challenge in Gram-positive bacteria. Here, we show that the inhibition of fatty acid and phospholipid synthesis caused by PlsX depletion leads to the accumulation of long-chain acyl-ACPs, the end products of the fatty acid synthase II. Hydrolysis of the acyl-ACP pool by heterologous expression of a cytosolic thioesterase relieves the inhibition of fatty acid synthesis, indicating that acyl-ACPs are feedback inhibitors of this metabolic route. Unexpectedly, inactivation of PlsX triggers a large increase of malonyl-CoA leading to induction of the fap regulon. This finding discards the hypothesis, proposed for B. subtilis and extended to other Gram-positive bacteria, that acyl-ACPs are feedback inhibitors of the acetyl-CoA carboxylase. Finally, we propose that the continuous production of malonyl-CoA during phospholipid synthesis inhibition provides an additional mechanism for fine-tuning the coupling between phospholipid and fatty acid production in bacteria with FapR regulation. 相似文献
83.
Giovanni Savettieri Rosa Guarneri Giuseppe Salemi Vincenzo La Bella Donatella Ferraro Salvatore Scondotto Federico Piccoli 《Neurochemical research》1990,15(8):773-776
[3H]Flunitrazepam (FNZ) binding to cortical neurons from fetal rat brain was investigated in vitro. The use of a synthetic medium specific for neurons made it possible to plot a developmental curve of3H-FNZ binding in an almost pure neuronal culture. Detectable specific binding was present in vitro at time 0 (that is, the 16th gestational day). A progressive increase of binding, due to an increment in the number of recognition sites, was observed on the subsequent days. The affinity of the specific binding sites to3H-FNZ was enhanced by the addition of exogenous GABA, whereas the density was not affected. 相似文献
84.
85.
Airborne pollen sampling in Toledo, Central Spain 总被引:2,自引:0,他引:2
Herminia García-Mozo Rosa Pérez-Badia Federico Fernández-González Carmen Galán 《Aerobiologia》2006,22(1):55-66
Toledo is one of the main tourist spots of Spain, attracting around two million visitors per year. Its geographical situation
in the vast and scarcely monitored Region of Castilla La Mancha and the high number of tourists (especially in the spring)
has resulted in the Spanish Aerobiology Network (REA) making this city a major study objective. Air monitoring studies carried
out using REA sampling procedures commenced in October 2002. Thirty-two pollen types were identified during the sampling period
(October 2002 to October 2004). The annual Pollen Index (PI) was 44124 for the agricultural year October 2002–October 2003,
and 29666 in the same period of 2003–2004. The most abundant taxa were, in decreasing order of dominance: Cupressaceae, Quercus, Poaceae, Populus, Olea, Urticaceae, Platanus, Pinus and Ulmus. Other, less well-represented pollen taxa included Salix, Alnus, Fraxinus and Tamarix, which were characteristic of riverside areas, and Morus, Artemisia and Chenopodiaceae. The presence of Castanea pollen grains originating from chestnut crops far away from the city was clearly an example of long-distance transport. The
highest concentrations of airborne pollen were detected from March to May and also in January, due to the flowering of Cupressaceae
species. In general, there was a correlation between pollen and meteorological parameters: a positive correlation with temperature
and a negative correlation with rainfall and humidity during the pre-peak period. A negative correlation between temperature
and some tree pollen taxa was detected in the principal pollen period correlation analysis due to their long pollination periods. 相似文献
86.
Determining the regulation of metabolic networks at genome scale is a hard task. It has been hypothesized that biochemical pathways and metabolic networks might have undergone an evolutionary process of optimization with respect to several criteria over time. In this contribution, a multi-criteria approach has been used to optimize parameters for the allosteric regulation of enzymes in a model of a metabolic substrate-cycle. This has been carried out by calculating the Pareto set of optimal solutions according to two objectives: the proper direction of flux in a metabolic cycle and the energetic cost of applying the set of parameters. Different Pareto fronts have been calculated for eight different "environments" (specific time courses of end product concentrations). For each resulting front the so-called knee point is identified, which can be considered a preferred trade-off solution. Interestingly, the optimal control parameters corresponding to each of these points also lead to optimal behaviour in all the other environments. By calculating the average of the different parameter sets for the knee solutions more frequently found, a final and optimal consensus set of parameters can be obtained, which is an indication on the existence of a universal regulation mechanism for this system.The implications from such a universal regulatory switch are discussed in the framework of large metabolic networks. 相似文献
87.
Sara Garcia‐Serrano Carolina Gutiérrez‐Repiso Montserrat Gonzalo Juan Garcia‐Arnes Sergio Valdes Federico Soriguer Vidal Perez‐Valero Miguel A. Alaminos‐Castillo Juan Francisco Cobos‐Bravo Francisco J. Moreno‐Ruiz Alberto Rodriguez‐Cañete Francisca Rodríguez‐Pacheco Eva Garcia‐Escobar Eduardo García‐Fuentes 《Obesity (Silver Spring, Md.)》2015,23(8):1607-1615
88.
Federico Giri Pablo Collins 《Biological journal of the Linnean Society. Linnean Society of London》2014,113(4):914-930
South America has been influenced by different geoclimatic events ever since its separation from Africa. The inland water fauna has evolved in response to the changing landscape. Currently, there are indications of variations in populations, occurring to different degrees that would indicate a clinal pattern in morphology. Among South America's fauna, the freshwater anomuran, Aegla, is an enigmatic group as a result of its endemicity and is composed of only one genus. Of all the species in this family, Aegla uruguayana has the broadest distribution. Its native habitats have been influenced by several marine transgressions during the Miocene–Quaternary Periods; thus, it is likely that their current distribution has been more recent. Its habitat spreads across a number of isolated basins and sub‐basins that display distinct degrees of isolation/connection, making clinal variation patterns in the morphology of this species possible. The present study aimed to evaluate the pattern of carapace shape variation in A. uruguayana and how it relates to the isolation and/or connection of populations from different basins and sub‐basins, allowing the determination of any extant clinal patterns. The specimens studied belong to 25 separate populations, representing all areas in which the species currently exists. A total of 523 crabs were analyzed. We identified 13 landmarks and four semi‐landmarks in the carapace. The aeglids were divided into seven size intervals to avoid an allometry effect. In each size category, shape relationships analyzed by principal component analysis suggest a geographical pattern corresponding to the distribution of the populations studied. An evaluation of covariation between body shape and geographical coordinates reveals a strong pattern and shows that population distribution had a significant effect on species morphology. Additionally, according to covariance analysis, the variation in shape was not associated with the environmental variables studied. We observed a clinal pattern throughout the species distribution, which could be attributed to genetic drift. It is possible that this process is being amplified by the geographical isolation of the basins, differences in environmental characteristics, and low dispersal ability. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 914–930. 相似文献
89.
Andrea M. Quiroga Federico J. Berli Daniela Moreno Juan B. Cavagnaro Rubén Bottini 《Journal of Plant Growth Regulation》2009,28(1):28-35
In many cultivars of Vitis vinifera periods of mild water stress during ripening are thought to increase grape quality for winemaking, even though yields may
be negatively affected. Because abscisic acid (ABA) is involved in the signaling of water stress in plants, we examine the
effects of the ABA signal being given without the concomitant water stress. ABA at 250 mg l−1 was sprayed weekly or biweekly from bud-burst until harvest onto the leaves of vineyard-grown plants of cv. Cabernet Sauvignon.
For ABA-treated plants berry yield per bunch and per plant was significantly increased (1.5- to 2.0-fold) across three consecutive
harvests (2005 through 2007). Number of berries per bunch and per plant was the primary basis for the significant crop increases,
although bunches per plant also tended to increase (1.1- to 1.3-fold) across all three harvests. Other parameters assessed
included number of internodes, shoot length, leaf area, leaf water potential at midday, photosynthesis, and stomatal conductance.
These parameters showed no significant change with ABA treatment, although shoot length tended to be reduced, as was leaf
area relative to control plants. The significantly increased fruit yields were thus accomplished without accompanying increases
in leaf photosynthesis and leaf areas. Juice at harvest had equal levels of sugars (Brix) and somewhat higher levels of anthocyanins
and total polyphenols relative to control values. The two latter trends continued for the resultant wine across two vintage
years. In conclusion, three seasons of experimental trials have demonstrated that ABA application can significantly enhance
yield per plant in the field-grown grape (cv. Cabernet Sauvignon) by favoring increased berry set without diminishing the
quality of the fruit for winemaking use. 相似文献
90.
Halberg F Cornélissen G Stoynev A Ikonomov O Katinas G Sampson M Wang Z Wan C Singh RB Otsuka K Sothern RB Sothern SB Sothern MI Syutkina EV Masalov A Perfetto F Tarquini R Maggioni C Kumagai Y Siegelova J Fiser B Homolka P Dusek J Uezono K Watanabe Y Wu J Prikryl P Blank M Blank O Sonkowsky R Schwartzkopff O Hellbrügge T Spector NH Baciu I Hriscu M Bakken E 《Neuro endocrinology letters》2003,24(6):479-498