Efecto del peróxido de hidrógeno en la expresión de proteínas durante la germinación

Comunicaciones a congreso

Cambios inducidos por Plum pox virus en el proteoma de plantas de melocotonero

Comunicaciones a congreso

Nitrate- and nitric oxide-induced plant growth in pea seedlings is linked to antioxidative metabolism and the ABA/GA balance

This study looks at the effects of potassium nitrate (KNO3) and sodium nitroprusside (SNP), a nitric oxide (NO)-donor, on the development, antioxidant defences and on the abscisic acid (ABA) and gibberellin (GA) levels inpea seedlings. Results show that 10 mM KNO3and 50μM SNP stimulate seedling fresh weight (FW), althoughthis effect is not reverted by the action of 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide(cPTIO), a NO-scavenger.The KNO3treatment increased peroxidase (POX) and ascorbate oxidase (AOX) activities. SNP, on the otherhand, reduced monodehydroascorbate reductase (MDHAR) activity and produced a significant increase in su-peroxide dismutase (SOD), POX and AOX activities. The“KNO3plus cPTIO”treatment increased ascorbateperoxidase (APX), MDHAR, glutathione reductase (GR) and SOD activities, but POX activity decreased in re-lation to the KNO3treatment. The“SNP plus cPTIO”treatment increased APX and MDHAR activities, whereas ahuge decrease in POX activity occurred. Both the KNO3and the SNP treatments increased reduced ascorbate(ASC) concentrations, which reached control values in the presence of cPTIO. All treatments increased thedehydroascorbate (DHA) level in pea seedlings, leading to a decrease in the redox state of ascorbate. In the“KNO3plus cPTIO”treatment, an increase in the redox state of ascorbate was observed. Glutathione contents,however, were higher in the presence of SNP than in the presence of KNO3. In addition, KNO3produced anaccumulation of oxidised glutathione (GSSG), especially in the presence of cPTIO, leading to a decrease in theredox state of glutathione. The effect of SNP on reduced glutathione (GSH) levels was reverted by cPTIO, sug-gesting that NO has a direct effect on GSH biosynthesis or turnover.Both the KNO3and SNP treatments produced an increase in GA4 and a decrease in ABA concentrations, andthis effect was reverted in the presence of the NO-scavenger. Globally, the results suggest a relationship betweenantioxidant metabolism and the ABA/GA balance during early seedling growth in pea. The results also suggest arole for KNO3and NO in the modulation of GA4 and ABA levels and antioxidant metabolism in pea seedlings.Furthermore, this effect correlated with an increase in the biomass of the pea seedlingsinfo:eu-repo/semantics/acceptedVersio

Metabolomics and biochemical approaches link salicylic acid biosynthesis to cyanogenesis in peach plants

Despite the long-established importance of salicylic acid (SA) in plant stress responses and other biological processes, its biosynthetic pathways have not been fully characterized. The proposed synthesis of SA originates from chorismate by two distinct pathways: the isochorismate and phenylalanine (Phe) ammonia-lyase (PAL) pathways. Cyanogenesis is the process related to the release of hydrogen cyanide from endogenous cyanogenic glycosides (CNglcs), and it has been linked to plant plasticity improvement. To date, however, no relationship has been suggested between the two pathways. In this work, by metabolomics and biochemical approaches (including the use of [C-13]-labeled compounds), we provide strong evidences showing that CNglcs turnover is involved, at least in part, in SA biosynthesis in peach plants under control and stress conditions. The main CNglcs in peach are prunasin and amygdalin, with mandelonitrile (MD), synthesized from phenylalanine, controlling their turnover. In peach plants MD is the intermediary molecule of the suggested new SA biosynthetic pathway and CNglcs turnover, regulating the biosynthesis of both amygdalin and SA. MD-treated peach plants displayed increased SA levels via benzoic acid (one of the SA precursors within the PAL pathway). MD also provided partial protection against Plum pox virus infection in peach seedlings. Thus, we propose a third pathway, an alternative to the PAL pathway, for SA synthesis in peach plantsThis work was supported by the Spanish Ministry of Economy and Competitiveness (Project AGL2014-52563-R). PDV and CP thank CSIC and UPCT, respectively, as well as the Spanish Ministry of Economy and Competitiveness for their ‘Ramon & Cajal’ research contract, co-financed by FEDER funds. We also acknowledge Prof. Manuel Acosta Echeverría for his very useful commentaries and discussion

Cytosolic ascorbate peroxidase and Cu, Zn-superoxide dismutase improve seed germination, plant growth, nutrient uptake and drought tolerance in tobacco

The effects of over-expression of two cytosolic antioxidant enzymes (Cu, Zn-SOD and/or APX) on plant nutrition, gas exchange, chlorophyll fluorescence, seed viability and germination in transgenic tobacco (Nicotiana tabacum cv. Xanthi) under deficit irrigation or salinity conditions were investigated. Three transgenic lines of tobacco were used in this study: line 17, harboring 2 copies of the cytosolic CuZn-SOD (cytsod) gene; line 51, with 2 copies of the cytosolic APX (cytapx) gene and line 39, harboring one copy of each gene. Over-expression of cytosolic antioxidants enzymes in tobacco plants resulted in a better growth performance that correlated with an improved photosynthetic capacity and nutrient uptake. Moreover, cytsod or cytapx genes promoted seed germination, and enhanced tolerance to mild water stress. In addition, this enhanced antioxidant capacity protected seeds from ageing during prolonged storage, and stimulated germination under salt stress conditions. These results suggest that cytosolic antioxidant transgenes are useful tools to improve drought tolerance, nutrient uptake and seed germination under stressful conditions.PDV acknowledges the CSIC and the Spanish Ministry of Economy and Competitiveness for his ‘Ramon y Cajal’ research contract, co-financed by FEDER funds. This work was supported by the Spanish Ministry of Economy and Competitiveness (Project CICYT BFU2009-07443) co-financed by FEDER funds, and the Spanish Ministry of Economy and Competitiveness (Project INIA, RTA2013-00026-C03-00).Peer reviewe

NaCl-induced physiological and biochemical adaptative mechanisms in the ornamental Myrtus communis L. plants

Physiological and biochemical changes in Myrtus communis L. plants after being subjected to different solutions of NaCl (44, and 88mM) for up to 30 days (Phase I) and after recovery from the salinity period (Phase II) were studied. Myrtle plants showed salinity tolerance by displaying a series of adaptative mechanisms to cope with salt-stress, including controlled ion homeostasis, the increase in root/shoot ratio, the reduction of water potentials and stomatal conductance to limit water loss. In addition, they displayed different strategies to protect the photosynthetic machinery, including limiting toxic ion accumulation in leaves, increase in chlorophyll content, and changes in chlorophyll fluorescence parameters, leaf anatomy and increases in catalase activity. Anatomical modifications in leaves, including a decrease in spongy parenchyma and increased intercellular spaces, allow CO2 diffusion in a situation of reduced stomatal aperture. In spite of all these changes, salinity produced oxidative stress in myrtle plants as monitored by increases in oxidative stress parameter values. The post-recovery period is perceived as a new stress situation, as observed through effects on plant growth and alterations in non-photochemical quenching parameters and lipid peroxidation values. © 2015 Elsevier GmbH.This work was supported by the Spanish Ministry of Economy and Competitiveness co-financed by FEDER funds (Project CICYT AGL 2011-30022-C02-01-02) and by The Fundación Séneca-Agencia de Ciencia y Tecnología de la Región de Murcia (11883/PI/09 and 15356/PI/10). PDV acknowledges the CSIC and the Spanish Ministry of Economy and Competitiveness for his ‘Ramon y Cajal’ research contract, co-financed by FEDER funds.Peer Reviewe

Physiological and biochemical mechanisms of the ornamental Eugenia myrtifolia L. plants for coping with NaCl stress and recovery

Main Conclusion: We studied the response ofEugenia myrtifoliaL. plants, an ornamental shrub native to tropical and subtropical areas, to salt stress in order to facilitate the use of these plants in Mediterranean areas for landscaping.E. myrtifoliaplants implement a series of adaptations to acclimate to salinity, including morphological, physiological and biochemical changes. Furthermore, the post-recovery period seems to be detected by Eugenia plants as a new stress situation. Different physiological and biochemical changes in Eugenia myrtifolia L. plants after being subjected to NaCl stress for up to 30 days (Phase I) and after recovery from salinity (Phase II) were studied. Eugenia plants proved to be tolerant to NaCl concentrations between 44 and 88 mM, displaying a series of adaptative mechanisms to cope with salt-stress, including the accumulation of toxic ions in roots. Plants increased their root/shoot ratio and decreased their leaf area, leaf water potential and stomatal conductance in order to limit water loss. In addition, they displayed different strategies to protect the photosynthetic machinery, including the limited accumulation of toxic ions in leaves, increase in chlorophyll content, changes in chlorophyll fluorescence parameters, leaf anatomy and antioxidant defence mechanisms. Anatomical modifications in leaves, including an increase in palisade parenchyma and intercellular spaces and decrease in spongy parenchyma, served to facilitate CO2 diffusion in a situation of reduced stomatal aperture. Salinity produced oxidative stress in Eugenia plants as evidenced by oxidative stress parameters values and a reduction in APX and ASC levels. Nevertheless, SOD and GSH contents increased. The post-recovery period is detected as a new stress situation, as observed through effects on plant growth and alterations in chlorophyll fluorescence and oxidative stress parameters. © 2015, Springer-Verlag Berlin Heidelberg.This work was supported by the Spanish Ministry of Economy and Competitiveness co-financed by FEDER funds (Project CICYT AGL 2011-30022-C02-01-02) and by The Fundación Séneca-Agencia de Ciencia y Tecnología de la Región de Murcia (11883/PI/09 and 15356/PI/10). Authors thank Mrs Ansley Evans for correction of the English.Peer Reviewe

Oxidative stress and antioxidative responses in plant-virus interactions

During plant–virus interactions, defence responses are linked to the accumulation of reactive oxygen species (ROS). Importantly, ROS play a dual role by (1) eliciting pathogen restriction and often localized death of host plant cells at infection sites and (2) as a diffusible signal that induces antioxidant and pathogenesis-related defence responses in adjacent plant cells. The outcome of these defences largely depends on the speed of host responses including early ROS accumulation at virus infection sites. Rapid host reactions may result in early virus elimination without any oxidative stress (i.e. a symptomless, extreme resistance). A slower host response allows a certain degree of virus replication and movement resulting in oxidative stress and programmed death of affected plant cells before conferring pathogen arrest (hypersensitive response, HR). On the other hand, delayed host attempts to elicit virus resistance result in an imbalance of antioxidative metabolism and massively stressed systemic plant tissues (e.g. systemic chlorotic or necrotic symptoms). The final consequence of these processes is a partial or almost complete loss of control over virus invasion (compatible infections).Research in the author's laboratories is supported by grants of the Hungarian Scientific Research Fund (K111995 and PD108455) and the Spanish Ministry of Economy and Competitiveness (Project INIA, RTA2013-00026-C03-00). PDV acknowledges the CSIC and the Spanish Ministry of Economy and Competitiveness for his ‘Ramon y Cajal’ research contract, cofinanced by FEDER funds. MJCM acknowledges the Spanish Ministry of Economy and Competitivenes for her ‘Juan de la Cierva’ research contract.Peer reviewe

Transcription, indexing and automatic analysis of judicial declarations from phonetic representations and techniques of forensic linguistics

Recientes avances tecnológicos han permitido mejorar los procesos judiciales para la búsqueda de información en los expedientes judiciales asociados a un caso. Sin embargo, cuando técnicos y peritos deben revisar pruebas almacenadas en vídeos y fragmentos de audio, se ven obligados a realizar una búsqueda manual en el documento multimedia para localizar la parte que desean revisar, lo cual es una tarea tediosa y que consume bastante tiempo. Para poder facilitar el desempeño de los técnicos, el presente proyecto consiste en un sistema que permite la transcripción e indexación automática de contenido multimedia basado en tecnologías de deep-learning en entornos de ruido y con múltiples interlocutores, así como la posibilidad de realizar análisis de lingüística forense sobre los datos para ayudar a los peritos a analizar los testimonios de modo que se aporten evidencias sobre la veracidad del mismo.Recent technological advances have made it possible to improve the search for information in the judicial files of the Ministry of Justice associated with a trial. However, when judicial experts examine evidence in multimedia files, such as videos or audio fragments, they must manually search the document to locate the fragment at issue, which is a tedious and time-consuming task. In order to ease this task, we propose a system that allows automatic transcription and indexing of multimedia content based on deep-learning technologies in noise environments and with multiple speakers, as well as the possibility of applying forensic linguistics techniques to enable the analysis of witness statements so that evidence on its veracity is provided.Este proyecto ha sido financiado por el Instituto de Fomento de la Región de Murcia con fondos FEDER dentro del proyecto con referencia 2018.08.ID+I.0025

Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p < 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics