Identificación de complejos organometálicos en tejidos vegetales mediante espectrometría de masas

1 .pdf (32 Pags.) copia de la presentación original del autor en la Jornada.Peer reviewe

Metabolite Profile Changes in Xylem Sap and Leaf Extracts of Strategy I Plants in Response to Iron Deficiency and Resupply

The metabolite profile changes induced by Fe deficiency in leaves and xylem sap of several Strategy I plant species have been characterized. We have confirmed that Fe deficiency causes consistent changes both in the xylem sap and leaf metabolite profiles. The main changes in the xylem sap metabolite profile in response to Fe deficiency include consistent decreases in amino acids, N-related metabolites and carbohydrates, and increases in TCA cycle metabolites. In tomato, Fe resupply causes a transitory flush of xylem sap carboxylates, but within 1 day the metabolite profile of the xylem sap from Fe-deficient plants becomes similar to that of Fe-sufficient controls. The main changes in the metabolite profile of leaf extracts in response to Fe deficiency include consistent increases in amino acids and N-related metabolites, carbohydrates and TCA cycle metabolites. In leaves, selected pairs of amino acids and TCA cycle metabolites show high correlations, with the sign depending of the Fe status. These data suggest that in low photosynthesis, C-starved Fe-deficient plants anaplerotic reactions involving amino acids can be crucial for short-term survival

Changes in the proteomic and metabolic profiles of Beta vulgaris root tips in response to iron deficiency and resupply

<p>Abstract</p> <p>Background</p> <p>Plants grown under iron deficiency show different morphological, biochemical and physiological changes. These changes include, among others, the elicitation of different strategies to improve the acquisition of Fe from the rhizosphere, the adjustment of Fe homeostasis processes and a reorganization of carbohydrate metabolism. The application of modern techniques that allow the simultaneous and untargeted analysis of multiple proteins and metabolites can provide insight into multiple processes taking place in plants under Fe deficiency. The objective of this study was to characterize the changes induced in the root tip proteome and metabolome of sugar beet plants in response to Fe deficiency and resupply.</p> <p>Results</p> <p>Root tip extract proteome maps were obtained by 2-D isoelectric focusing polyacrylamide gel electrophoresis, and approximately 140 spots were detected. Iron deficiency resulted in changes in the relative amounts of 61 polypeptides, and 22 of them were identified by mass spectrometry (MS). Metabolites in root tip extracts were analyzed by gas chromatography-MS, and more than 300 metabolites were resolved. Out of 77 identified metabolites, 26 changed significantly with Fe deficiency. Iron deficiency induced increases in the relative amounts of proteins and metabolites associated to glycolysis, tri-carboxylic acid cycle and anaerobic respiration, confirming previous studies. Furthermore, a protein not present in Fe-sufficient roots, dimethyl-8-ribityllumazine (DMRL) synthase, was present in high amounts in root tips from Fe-deficient sugar beet plants and gene transcript levels were higher in Fe-deficient root tips. Also, a marked increase in the relative amounts of the raffinose family of oligosaccharides (RFOs) was observed in Fe-deficient plants, and a further increase in these compounds occurred upon short term Fe resupply.</p> <p>Conclusions</p> <p>The increases in DMRL synthase and in RFO sugars were the major changes induced by Fe deficiency and resupply in root tips of sugar beet plants. Flavin synthesis could be involved in Fe uptake, whereas RFO sugars could be involved in the alleviation of oxidative stress, C trafficking or cell signalling. Our data also confirm the increase in proteins and metabolites related to carbohydrate metabolism and TCA cycle pathways.</p

Rapid alteration of cellular redox homeostasis upon exposure to cadmium and mercury in alfalfa seedlings.

Summary • Here, the kinetics of oxidative stress responses of alfalfa ( Medicago sativa ) seedlings to cadmium (Cd) and mercury (Hg) (0, 3, 10 and 30 µ M ) exposure, expanding from a few minutes to 24 h, were studied. • Intracellular oxidative stress was analysed using 2 ′ ,7 ′ -dichlorofluorescin diacetate and extracellular hydrogen peroxide (H 2 O 2 ) production was studied with Amplex Red. Growth inhibition, concentrations of ascorbate, glutathione (GSH), homoglutathione (hGSH), Cd and Hg, ascorbate peroxidase (APX) activity, and expression of genes related to GSH metabolism were also determined. • Both Cd and Hg increased cellular reactive oxygen species (ROS) production and extracellular H 2 O 2 formation, but in different ways. The increase was mild and slow with Cd, but more rapid and transient with Hg. Hg treatments also caused a higher cell death rate, significant oxidation of hGSH, as well as increased APX activity and transient overexpression of glutathione reductase 2, glutamylcysteinyl synthetase, and homoglutathione synthetase genes. However, Cd caused minor alterations. Hg accumulation was one order of magnitude higher than Cd accumulation. • The different kinetics of early physiological responses in vivo to Cd and Hg might be relevant to the characterization of their mechanisms of toxicity. Thus, high accumulation of Hg might explain the metabolism poisoning observed in Hg-treated seedlings

New Palaeolithic sites from the Depresión de Monforte de Lemos (Lugo, Galicia, Spain)

Este artículo presenta el descubrimiento de nuevos yacimientos paleolíticos en la Depresión de Monforte de Lemos (Noroeste de la Península Ibérica). Esta zona fue rellenada con depósitos cuaternarios que han proporcionado más de 30 yacimientos al aire libre. Como consecuencia del descubrimiento casual de artefactos paleolíticos, se ha desarrollado un proyecto de intervención arqueológica sistemática, que ha demostrado el potencial de esta área. Muchos de los artefactos líticos han sido hallados en superficie, pero además contamos con dos yacimientos que tienen materiales en contexto estratigráfico (O Regueiral y Áspera). En la Depresión de Monforte hemos atestiguado poblamiento humano a lo largo del Pleistoceno medio y superior, con implementos líticos clasificados como Modo 2, Modo 3 y Modo 4. Los yacimientos más importantes son As Lamas, Chao de Fabeiro (ambos con industria lítica de Modo 2, que incluye bifaces y hendedores), O Regueiral (Modo 3) y Valverde (Modo 4). Por consiguiente, la Depresión de Monforte reúne las condiciones apropiadas para el desarrollo de un estudio diacrónico sobre la evolución del comportamiento técnico durante el Paleolítico, y su relación con la evolución del medioambiente a lo largo del PleistocenoThis paper reports the discovery of new Paleolithic sites in the Depresión de Monforte de Lemos (Monforte Basin, NW of the Iberian Peninsula). This zone was filled with Quaternary deposits that have yielded 30 open air sites. Due to the casual discovery of Paleolithic artifacts a systematic archaeological work was carried out, assessing the archaeological potential of this area. Most of these lithic artifacts were found on surface, but also we have located two sites with archaeological materials in stratigraphic context (O Regueiral and Áspera). In the basin of Monforte we have recognized a human settlement along the Middle and Upper Pleistocene, with lithic implements classified as Mode 2, Mode 3 and Mode 4. The most important sites are As Lamas, Chao de Fabeiro (both with Mode 2 lithic industry, that includes handaxes and cleavers), O Regueiral (Mode 3), and Valverde (Mode 4). Thus the Monforte Basin has the adequate conditions to accomplish a diachronic study on the evolution of the strategies of technical behavior during the Paleolithic, and its relation with the evolution of Pleistocene environmentEste trabajo se enmarca en el proyecto de investigación “Ocupaciones humanas durante el Pleistoceno de la Cuenca media del Miño” financiado por el Ministerio de Educación y Ciencia y fondos FEDER de la UE (HUM2007-63662/HIST)S

Morphological Plant Modeling: Unleashing Geometric and Topological Potential within the Plant Sciences

The geometries and topologies of leaves, flowers, roots, shoots, and their arrangements have fascinated plant biologists and mathematicians alike. As such, plant morphology is inherently mathematical in that it describes plant form and architecture with geometrical and topological techniques. Gaining an understanding of how to modify plant morphology, through molecular biology and breeding, aided by a mathematical perspective, is critical to improving agriculture, and the monitoring of ecosystems is vital to modeling a future with fewer natural resources. In this white paper, we begin with an overview in quantifying the form of plants and mathematical models of patterning in plants. We then explore the fundamental challenges that remain unanswered concerning plant morphology, from the barriers preventing the prediction of phenotype from genotype to modeling the movement of leaves in air streams. We end with a discussion concerning the education of plant morphology synthesizing biological and mathematical approaches and ways to facilitate research advances through outreach, cross-disciplinary training, and open science. Unleashing the potential of geometric and topological approaches in the plant sciences promises to transform our understanding of both plants and mathematics

Making microscopy count: quantitative light microscopy of dynamic processes in living plants

First published: April 2016This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Cell theory has officially reached 350 years of age as the first use of the word ‘cell’ in a biological context can be traced to a description of plant material by Robert Hooke in his historic publication “Micrographia: or some physiological definitions of minute bodies”. The 2015 Royal Microscopical Society Botanical Microscopy meeting was a celebration of the streams of investigation initiated by Hooke to understand at the sub-cellular scale how plant cell function and form arises. Much of the work presented, and Honorary Fellowships awarded, reflected the advanced application of bioimaging informatics to extract quantitative data from micrographs that reveal dynamic molecular processes driving cell growth and physiology. The field has progressed from collecting many pixels in multiple modes to associating these measurements with objects or features that are meaningful biologically. The additional complexity involves object identification that draws on a different type of expertise from computer science and statistics that is often impenetrable to biologists. There are many useful tools and approaches being developed, but we now need more inter-disciplinary exchange to use them effectively. In this review we show how this quiet revolution has provided tools available to any personal computer user. We also discuss the oft-neglected issue of quantifying algorithm robustness and the exciting possibilities offered through the integration of physiological information generated by biosensors with object detection and tracking

GLO-Roots: an imaging platform enabling multidimensional characterization of soil-grown root systems

Root systems develop different root types that individually sense cues from their local environment and integrate this information with systemic signals. This complex multi-dimensional amalgam of inputs enables continuous adjustment of root growth rates, direction, and metabolic activity that define a dynamic physical network. Current methods for analyzing root biology balance physiological relevance with imaging capability. To bridge this divide, we developed an integrated-imaging system called Growth and Luminescence Observatory for Roots (GLO-Roots) that uses luminescence-based reporters to enable studies of root architecture and gene expression patterns in soil-grown, light-shielded roots. We have developed image analysis algorithms that allow the spatial integration of soil properties, gene expression, and root system architecture traits. We propose GLO-Roots as a system that has great utility in presenting environmental stimuli to roots in ways that evoke natural adaptive responses and in providing tools for studying the multi-dimensional nature of such processes. DOI: http://dx.doi.org/10.7554/eLife.07597.00