La lectura y los trastornos en su aprendizaje

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FleN and FlhF as new regulatory elements in the lifestyle switch in Pseudomonas putida

Motivation:Pseudomonas putida is a soil bacterium that can be found in nature as individual motile cells or as part of sessile communities called biofilms (1). Biofilm formation could be considered an adaptive strategy as it provide higher resistance against adverse agents, antimicrobial treatments, ultraviolet radiation or dehydration, increasing bacteria survival (2). The switch from a planktonic lifestyle to biofilm formation in P.putida is regulated by FleQ and the intracellular levels of c-di-GMP (3). Isolation of insertion mutants in flhF gene, defective in biofilm formation, suggests the involvement of additional elements in the regulation of this process. In this work, we have characterized the transcriptional organization of flhA, flhF, fleN and fliA genes and the role of FlhF and FleN in biofilm development in P.putida. Methods: Planktonic growth and biofilm formation curves, adhesion and swimming-motility assays. Gene expression analysis: β-galactosidase assays and RT-PCR. Electrophoretic mobility shift assays (EMSA).Results and Conclusions: To test the role of FlhF and FleN in biofilm development, we carried out a phenotypic characterization of ΔflhF and ΔfleN mutants. Experiments shown that ΔfleN mutant is not able to form biofilm whereas ΔflhF mutant exhibits a wild-type phenotype. Adhesion assays indicate that ΔfleN mutant has a reduced adhesion, whereas ΔflhF can properly adhere to the surface. On the other hand, both mutant show reduced swimming motility. These resuts suggests that both, FleN and FlhF, are involved in swimming motility, but only FleN is necessary for biofilm formation, probably by altering adhesion capacity of the bacteria. Bioinformatic tools predict that flhF and fleN form an operon with the upstream gene flhA and the downstream gene fliA. In order to corroborate this hypothesis, we have done RT-PCR using RNA from the mutants. Results shown that these genes are structured in a single operon: flhAFfleNfliA.To determine a possible regulatory role of these elements in biofilm formation and motility, β-galactosidase assays were performed to analyse the expression of biofilm and flagellum related promoters. Results shown that FleN downregulates both types of promoters whereas FlhF is only involved in the regulation of one flagellar gene. The regulatory role of FleN has been further studied in vitro by EMSA with the regulator FleQ. Results suggest that FleN is required for FleQ to bind to its target promoters

Prevalence of Developmental Dyslexia in Spanish University Students

A recent concern in the field of dyslexia studies is the lack of awareness and attention to university students suffering from this condition. If this problem is serious in countries where the relative opacity of the writing system allows for an early detection and, therefore, effective interventions, it is most critical in countries where transparent spelling makes such detection difficult, except in the most severe cases. In Spain, the diagnosis of dyslexia is rare among university-level adults. The present study pursues three aims: (a) to put forward a screening instrument for the detection of university students at risk of dyslexia, (b) to determine the ratio of university students that could be at risk of dyslexia by means of two different procedures, and (c) to create awareness for a disorder that causes hitherto unrecognized difficulties for an important subgroup of the college population. Six hundred and eighty-six university students in four different fields of study within the general area of Social Sciences from a public University in Madrid completed a Spanish-adapted version of a protocol including stress assignment, spelling words and nonwords, and timed phonological working memory of reading and writing task. Results showed that between 1.6% and 6.4% of this population could be at risk of suffering dyslexia. Such risk is not evenly distributed across the four fields of study. As for gender, the first criterion used yields 1.8 males at risk for every female, but the second criterion has as many males as females at risk. Women were significantly better than men in word spelling. Spelling was best predicted by the timed phonological working memory task of reading and writing

Effects of Sodium Chloride-Rich Mineral Water on Intestinal Epithelium. Experimental Study

This study was financed by the research groups CTS-115 (Universidad de Granada, Tissue Engineering) and UCM-911757 (Universidad Complutense de Madrid, Medical Hydrology).Since knowledge concerning the cellular and tissue substrate that explains the therapeutic action of mineral waters is generally very scarce, we address the different effects that Lanjaron-Capuchina mineral water exerts on the intestinal epithelium in an experimental model as a prototype of the sodium chloride-rich mineral waters used in digestive disorders. In the experimental protocol, two groups of five adult Wistar rats received unrestricted mineral water in their diet or mineral water directly into the gastrointestinal tract through a catheter. A third control group was given a standard diet and water ad libitum. Intestinal samples for scanning electron microscopy were analyzed according to standardized methods. The observations carried out by microscope after the administration of the sodium chloride-rich mineral water clearly indicate that the hypertonic action of this mineral water affects the structure of the intestinal epithelium. It modifies the microvilli absorption in terms of the groups of enterocytes and the secretion of goblet cells, but it particularly affects the epithelial renewal process, accelerating and stimulating cell extrusion. The type of extrusion mechanism observed by microscope allows us to affirm that, although this increased after direct administration, it does not generate an epithelial disruption as it occurs in other circumstances with other extrusion modalities.Universidad de Granada, Tissue Engineering CTS-115Universidad Complutense de Madrid, Medical Hydrology UCM-91175

The interplay between zinc and iron homeostasis in Aspergillus fumigatus under zinc-replete conditions relies on the iron-mediated regulation of alternative transcription units of zafA and the basal amount of the ZafA zinc-responsiveness transcription factor

[EN] Aspergillus fumigatus is a saprophyte fungus that typically grows on organic decaying matter but can also parasitize immunosuppressed hosts. This is explained, in part, by its great ability to take up Zn2+ ions from living tissues, which is induced by the ZafA transcription factor. This study shows that the ZafA-mediated regulation of fungal growth is also influenced by iron availability and that A. fumigatus is well adapted to grow in zinc-limiting and zinc-replete media with Zn:Fe ratios lower in the former than in the latter. Accordingly, this indicates that iron availability appears to be more critical for fungal growth in zinc-replete than in zinc-limiting environments. Interestingly, the cross-regulation of zinc/iron homeostasis under zinc-replete conditions relies on an unprecedented iron-mediated regulation of different zafA transcription units that, along with a limited transcript translation, allows synthesizing the right basal amount of ZafA dependent on iron availability. We posit that this regulatory strategy has evolved in fungi as a mechanism to adjust zinc intake to iron availability under zinc-replete conditions. Thus, fungal growth is enhanced in zinc- and iron-replete media but restricted by reducing zinc intake under iron starvation to prevent the noxious side effects of an intracellular zinc excess during iron deficiency

Modelos animales y aplicaciones terapeúticas de la edición génica mediante CRISPR-CAS

Memoria ID-065. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2018-2019

Abundance of Anchovy eggs by CUFES: Inter-annual fluctuations and spatial patterns.

Data on the abundance of Anchovy eggs in the Gulf of Cadiz as collected by CUFES are explored in the present work in relation to their spatial pattern and inter-annual fluctuations. These data were gathered in 12 summer surveys, both acoustic (ECOCADIZ series) and DEPM (BOCADEVA series) ones, since 2004 to date (no survey in 2012). A total of 1499 CUFES stations were sampled, which distributed from the strait of Gibraltar, in Spain, to Cape San Vicente, in Portugal (in 2010 to Cape Sta. Maria only). The sampling scheme consisted in a grid of 21 parallel transects, normal to the shoreline and inter-spaced 8 nm, with the samples being collected every 3 nm at a c.a. 600 l/min flow with a 335 μm mesh size net and at a sampling depth of 5 m from the surface. A continuous record of SST and SSS at 5 m (termosalinometer) was coupled to the CUFES sampling. The surveys were carried out in June, July or August depending on the year. Oceanographic variables such as temperature, salinity and chlorophyll, and even the bottom topography of the shelf as well, they all showed significantly different in two regions: to the East and West of the Cape S. Mª. The density of Anchovy eggs presents a high variability between stations showing a very patched distribution. The stations with most eggs are located to the East of Cape Sta. Mª. Egg abundance also showed a very high between-year variability, ranging from 2955 eggs in 2005 to 41941 eggs collected in 2014. Regarding the spatial pattern of egg distribution, the 84.9% of the total egg density (all the surveys pooled) was collected in the area east of the Cape Sta. Mª (37.4 % in 2016), and the 89.8 % of total egg density in stations bellow 100 m depth (47.9 % in 2016). What happened in 2016? The mean temperature registered in 2016 in the Western stratum (22.0ºC) was practically the same that the mean temperature registered from 2004 to 2015 in the Eastern stratum (21.7ºC). The analysis of the centers of gravity of the eggs densities vs longitude and depth show significant trends, but not for latitude, which indicate a displacement towards the West in 2016. However, no trends were found in the centers of gravity of the acoustic energy (NASC) as a proxy of adults. Is then the westward displacement of the spawning in 2016 caused by an advective transport (currents and/or winds) or by other causes? What will be the further effect on recruitment? It would be good to obtain a statistical model in order to explain how the different variables affect the abundance of eggs, including other variables like the wind, tide... The presence of deep canyons crossing the shelf in the East of Cape Sta. Mª indicates that distance to the coast would be a better variable than depth

Edición génica mediante el sistema CRISPR-Cas

Memoria ID-0069. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2017-2018

Spatio-temporal variability of mid-size pelagic fishes in the Gulf of Cadiz shelf waters in relation to climatic and environmental drivers

Understanding spatio-temporal distribution patterns of mid-size pelagic fish species (MSPF) is of great interest from the standpoint of both their management and conservation. MSPF inhabiting in the Gulf of Cadiz (SW Iberian Peninsula, Atlantic Ocean) are relevant because they contribute to a large number of individuals captured by the different fishing métiers operating in the area. So far, information on their spatial distribution and temporal changes remain scarce in the study area despite their implications in their stock discrimination and management. Herein, temporal changes of the distribution patterns of abundance and their response to environmental drivers of five MSPF (Scomber colias, Scomber scombrus, Trachurus trachurus, Trachurus mediterraneus and Trachurus picturatus) off the Gulf of Cadiz (GoC) are analyzed from acoustic surveys data for the period 2007-2017. In particular, we evaluated intra- and inter-specific overlapping over time and space using four spatial indices. The species’ abundance and distribution were estimated and mapped by applying geostatistical techniques taking into account autocorrelation between observations. Furthermore, analyses including environmental variables were tested to explain such spatial fluctuations. The main findings showed a progressive reduction of their distribution area in all species over time except for T. trachurus. The only species overlapping in space and time wasbetween T. picturatus and S. colias. The distribution areas of S. colias and T. mediterraneus were notably reduced and showed northern/southern preferences over the years. The main environmental variables shaping the abundance and distribution of each species were found to be chlorophyll and temperature. Climatic indices such as NAO and AMO affected MSPF by reducing or increasing their spatial distribution. Finally, we discuss implications of our findings to contribute to the implementation of the Marine Strategy Framework Directive in the frame of implementing an effective ecosystem approach to fisheries management in the region