Genètica i Citogenètica: Pràctiques de Laboratori

El quadern de pràctiques forma part dels materials docents programats mitjançant l'ajut del Servei de Política Lingüística de la Universitat de ValènciaQuadern de pràctiques de Genètica i Citogenètica. Grau Bioquímica i Ciències Biomèdiques.PRÀCTICA 1. Segregació de caràcters en Drosophila. Observació de la segregació independent enfront de la segregació de gens lligats. Aplicació de l’anàlisi estadística als resultats experimentals. Càlcul de la distància entre gens lligats. PRÀCTICA 2. Cromosomes politènics de Drosophila. Preparació i observació de cromosomes politènics. Detecció i estudi d’inversions cromosòmiques. PRÀCTICA 3. Aspectes citogenètics dels cromosomes sexuals: cromatina sexual. Preparació i observació d’extensions de cèl·lules de la mucosa bucal. Identificació de corpuscles de Barr. Comparació entre cèl·lules masculines i femenines

γ-Al2O3 as acid catalyst for dehydration of glucose to 5-hydroxymethylfurfural

Currently, the search and development of sustainable feedstocks for chemicals derived from petrol have gained worldwide attraction because of the instability of the price of crude oil, the reduction of fossil oil reserves, and the environmental concerns associated to the greenhouse effect caused by CO2 emissions, being biomass one of the world’s most important renewable carbon sources. The major component of plant-derived biomass are carbohydrates, being of great importance to develop efficient and green approaches to their valorization by conversion into high value-added products. Thus, glucose can be transformed by dehydration into 5-hydroxymethylfurfural (HMF), which is a versatile and key intermediate for the production of a wide variety of biobased chemicals and it is attracting much attention in biofuels and chemical industry. Different catalytic systems have been evaluated for HMF production from C6 carbohydrates as glucose, mostly based on heterogeneous catalysis as alternative to the use of liquid mineral acids. On the other hand, the high surface area, large pore size and thermal and hydrothermal stabilities of some mesoporous solids make them suitable for many catalytic processes. In the present work, the dehydration of glucose to HMF has been evaluated by using different mesoporous γ-Al2O3 with acid, neutral or basic character, in a biphasic water–MIBK solvent system to avoid the HMF degradation and its possible reaction with the intermediates from glucose to give soluble polymers and humins or acetalization with glucose. Different experimental parameters, such as reaction temperature and time, as well as the addition of inorganic salts have been studied in order to reach the maximum HMF yield.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Ministry of Economy and Competitiveness (CTQ2012-38204-C04-02 project), Junta de Andalucía (RNM-1565) and FEDER fund

Evaluación de la usabilidad de un sitio web educativo y de promoción de la salud en el contexto universitario

El objetivo del estudio fue la evaluación de la usabilidad del sitio web www.unidadsalud.es, dedicado a la promoción y formación en materia de salud, empleando una metodología mixta, con expertos y usuarios. Los resultados obtenidos muestran los errores detectados y su gravedad. Los resultados proporcionan mejoras que pueden ayudar a la implementación y mejora de la web para que sea un lugar de referencia en materia de salud, a través de la actividad física. Usability evaluation of an educational website and promotion of health in the university context Abstract The objective of this study was to evaluate the usability of www.unidadsalud.es website dedicated to the promotion and formation in health, using a mixed methodology, with experts and users. The results show the errors detected and its severity. The results provide improvements that can assist in the implementation and improvement, to be a landmark in health through physical activity

Effect of oligonucleotide primers in determining viral variability within hosts

BACKGROUND: Genetic variability in viral populations is usually estimated by means of polymerase chain reaction (PCR) based methods in which the relative abundance of each amplicon is assumed to be proportional to the frequency of the corresponding template in the initial sample. Although bias in template-to-product ratios has been described before, its relevance in describing viral genetic variability at the intrapatient level has not been fully assessed yet. RESULTS: To investigate the role of oligonucleotide design in estimating viral variability within hosts, genetic diversity in hepatitis C virus (HCV) populations from eight infected patients was characterised by two parallel PCR amplifications performed with two slightly different sets of primers, followed by cloning and sequencing (mean = 89 cloned sequences per patient). Population genetics analyses of viral populations recovered by pairs of amplifications revealed that in seven patients statistically significant differences were detected between populations sampled with different set of primers. CONCLUSIONS: Genetic variability analyses demonstrates that PCR selection due to the choice of primers, differing in their degeneracy degree at some nucleotide positions, can eclipse totally or partially viral variants, hence yielding significant different estimates of viral variability within a single patient and therefore eventually producing quite different qualitative and quantitative descriptions of viral populations within each host

Anti-fat bias in secondary school teachers: Are physical education teachers more biased than mathematics teachers?

t has been suggested that physical education (PE) teachers hold strong anti-fat attitudes and thatthese can have an impact on the health of their students. In this study, we compare the attitudesand stereotypes towards obesity of PE teachers with those of their colleagues who teachmathematics. In addition, we evaluated the association between the teachers’ anti-fat biases andthe level of physical activity (PA) of their students. The sample consisted of 81 PE teachers and 75mathematics teachers. The adolescent sample consisted of 1792 secondary school students. Theassessment of attitudes and stereotypes was conducted with the Implicit Association Test and theAnti-Fat Attitudes questionnaire. The PA level of the adolescents was determined by a self-administered instrument. PE and mathematics teachers showed similar biases, except for theautomatic obesity–laziness association, which was stronger for PE teachers than for mathematicsteachers. These distinctive implicit stereotypes of PE teachers were also significant predictors ofthe lack of PA in adolescents. We recommend the use of interventions aimed at reducing non-traditional forms of prejudice in teachers

Expression of miR159 is altered in tomato plants undergoing drought stress

In a scenario of global climate change,water scarcity is amajor threat for agriculture, severely limiting crop yields. Therefore, alternatives are urgently needed for improving plant adaptation to drought stress. Among them, gene expression reprogramming by microRNAs (miRNAs) might offer a biotechnologically sound strategy. Drought-responsive miRNAs have been reported in manyplant species, and some of them are known to participate in complex regulatory networks via their regulation of transcription factors involved in water stress signaling. We explored the role of miR159 in the response of Solanum lycopersicum Mill. plants to drought stress by analyzing the expression of sly-miR159 and its target SlMYB transcription factor genes in tomato plants of cv. Ailsa Craig grown in deprived water conditions or in response to mechanical damage caused by the Colorado potato beetle, a devastating insect pest of Solanaceae plants. Results showed that sly-miR159 regulatory function in the tomato plants response to distinct stresses might be mediated by differential stress-specific MYB transcription factor targeting. sly-miR159 targeting of SlMYB33 transcription factor transcript correlated with accumulation of the osmoprotective compounds proline and putrescine, which promote drought tolerance. This highlights the potential role of sly-miR159 in tomato plants' adaptation to water deficit conditions

Intronic hammerhead ribozymes in mRNA biogenesis

[EN] Small self-cleaving ribozymes are a group of natural RNAs that are capable of catalyzing their own and sequence-specific endonucleolytic cleavage. One of the most studied members is the hammerhead ribozyme (HHR), a catalytic RNA originally discovered in subviral plant pathogens but recently shown to reside in a myriad of genomes along the tree of life. In eukaryotes, most of the genomic HHRs seem to be related to short interspersed retroelements, with the main exception of a group of strikingly conserved ribozymes found in the genomes of all amniotes (reptiles, birds and mammals). These amniota HHRs occur in the introns of a few specific genes, and clearly point to a preserved biological role during pre-mRNA biosynthesis. More specifically, bioinformatic analysis suggests that these intronic ribozymes could offer a new form of splicing regulation of the mRNA of higher vertebrates. We review here the latest advances in the discovery and biological characterization of intronic HHRs of vertebrates, including new conserved examples in the genomes of the primitive turtle and coelacanth fishThis work was supported by the Ministerio de Economia y Competitividad of Spain (BFU2011-23398) to MdlP.García Robles, I.; Sanchez Navarro, JA.; La Peña Del Rivero, MD. (2012). Intronic hammerhead ribozymes in mRNA biogenesis. Biological Chemistry. 393(11):1317-1326. https://doi.org/10.1515/hsz-2012-0223S131713263931

Nutritional profile of multiple sclerosis

[EN]Background: multiple sclerosis (MS) is an inflammatory, neurodegenerative disease of the central nervous system. Weight loss and malnutrition are prevalent in advanced stages of MS. Objective: the aim of this study was to define the nutritional profile in moderate-advanced MS (especially by documenting malnutrition) and its evolution. Methods: a case-control study was designed; cross-sectional observational study was complemented by a 12-month prospective longitudinal observational study of MS patients. Nutritional status was evaluated by collecting clinical, anthropometric, dietary and analytical data. Results: one hundred and twenty-four patients with MS and 62 controls were recruited; 8% of the patients were malnourished or at risk of malnutrition. Only MS patients with advanced disability needed nutritional support. During the follow-up, five patients died and four of them received nutritional support. Conclusions: malnutrition was unusual in our sample of patients with moderate-advanced MS. The need for nutritional support is related to dysphagia in patients with advanced neurological disability. The nutritional status of patients with moderate-advanced MS is defined by a tendency to overweight and by the decrease in basal energy expenditure and handgrip strength test in relation to the loss of muscle mass. The deficient intake of polyunsaturated fatty acids, fiber and vitamin D is exacerbated in the evolution of the disease

Identification of stress associated microRNAs in Solanum lycopersicum by high-throughput Sequencing

Tomato (Solanum lycopersicum) is one of the most important crops around the world and also a model plant to study response to stress. High-throughput sequencing was used to analyse the microRNA (miRNA) profile of tomato plants undergoing five biotic and abiotic stress conditions (drought, heat, P. syringae infection, B. cinerea infection, and herbivore insect attack with Leptinotarsa decemlineata larvae) and one chemical treatment with a plant defence inducer, hexanoic acid. We identified 104 conserved miRNAs belonging to 37 families and we predicted 61 novel tomato miRNAs. Among those 165 miRNAs, 41 were stress-responsive. Reverse transcription quantitative PCR (RT-qPCR) was used to validate high-throughput expression analysis data, confirming the expression profiles of 10 out of 11 randomly selected miRNAs. Most of the differentially expressed miRNAs were stress-specific, except for sly-miR167c-3p upregulated in B. cinerea and P. syringae infection, sly-newmiR26-3p upregulated in drought and Hx treatment samples, and sly-newmiR33-3p, sly-newmiR6-3p and sly-newmiR8-3p differentially expressed both in biotic and abiotic stresses. From mature miRNAs sequences of the 41 stress-responsive miRNAs 279 targets were predicted. An inverse correlation between the expression profiles of 4 selected miRNAs (sly-miR171a, sly-miR172c, sly-newmiR22-3p and sly-miR167c-3p) and their target genes (Kinesin, PPR, GRAS40, ABC transporter, GDP and RLP1) was confirmed by RT-qPCR. Altogether, our analysis of miRNAs in different biotic and abiotic stress conditions highlight the interest to understand the functional role of miRNAs in tomato stress response as well as their putative targets which could help to elucidate plants molecular and physiological adaptation to stress

The Histone Marks Signature in Exonic and Intronic Regions Is Relevant in Early Response of Tomato Genes to Botrytis cinerea and in miRNA Regulation

Research into the relationship between epigenetic regulation and resistance to biotic stresses provides alternatives for plant protection and crop improvement. To unravel the mechanisms underlying tomato responses to Botrytis cinerea, we performed a chromatin immunoprecipitation (ChIP) analysis showing the increase in H3K9ac mark along the early induced genes SlyDES, SlyDOX1, and SlyLoxD encoding oxylipin-pathway enzymes, and SlyWRKY75 coding for a transcriptional regulator of hormonal signaling. This histone mark showed a more distinct distribution than the previously studied H3K4me3. The RNAPol-ChIP analysis reflected the actual gene transcription associated with increased histone modifications. A different pattern of marks in the oxylipin-related genes against P. syringae supported a pathogen-specific profile, while no significant differences occurred in SlyWRKY75. The epigenetic regulation of SlyWRKY75 by the intron-binding miR1127-3p was supported by the presence of SlyWRKY75 pre-mRNA in control plants. Interestingly, mRNA was found to be accumulated in response to B. cinerea and P. syringae, while reduction in miRNA only occurred against B. cinerea. The intronic region presented a similar pattern of marks than the rest of the gene in both pathosystems, except for H3K4me3 in the miRNA binding site upon B. cinerea. We located the gene encoding Sly-miR1127-3p, which presented reduced H3K4me3 on its promoter against B. cinerea