Per una Carta de Drets Socials com a procés de construcció de la ciutadania social comunitària

El sistema públic de Serveis Socials està patint un atac governamental sense precedents amb l'excusa de la crisi. Es pretén derrocar les conquestes socials que han sigut el fonament de la democràcia, precisament ara que la desigualtat social és cada dia mes descarada. Per açò des del col•lectiu volem aportar el nostre granet de sorra proposant un procés que contribuïsca a reforçar la base comunitària des de la participacióThe public system of Social Services is suffering an unprecedented government attack, using the global crisis as an excuse. Their plan is to ruin the social achievements that are the foundations of our Democracy, just when the social inequality is blatant. Therefore, we would like to do our bit by proposing the implementation of a new process that contributes to strengthen the Community participation

Proteomic Analysis of Chloroplast-to-Chromoplast Transition in Tomato Reveals Metabolic Shifts Coupled with Disrupted Thylakoid Biogenesis Machinery and Elevated Energy-Production Components

A comparative proteomic approach was performed to identify differentially expressed proteins in plastids at three stages of tomato(Solanum lycopersicum) fruit ripening (mature-green, breaker, red). Stringent curation and processing of the data from three independent replicates identified 1,932 proteins among which 1,529 were quantified by spectral counting. The quantification procedures have been subsequently validated by immunoblot analysis of six proteins representative of distinct metabolic or regulatory pathways. Among the main features of the chloroplast-to-chromoplast transition revealed by the study, chromoplastogenesis appears to be associated with major metabolic shifts: (1) strong decrease in abundance of proteins of light reactions (photosynthesis, Calvin cycle, photorespiration)and carbohydrate metabolism (starch synthesis/degradation), mostly between breaker and red stages and (2) increase in terpenoid biosynthesis (including carotenoids) and stress-response proteins (ascorbate-glutathione cycle, abiotic stress, redox, heat shock). These metabolic shifts are preceded by the accumulation of plastid-encoded acetyl Coenzyme A carboxylase D proteins accounting for the generation of a storage matrix that will accumulate carotenoids. Of particular note is the high abundance of proteins involved in providing energy and in metabolites import. Structural differentiation of the chromoplast is characterized by a sharp and continuous decrease of thylakoid proteins whereas envelope and stroma proteins remain remarkably stable. This is coincident with the disruption of the machinery for thylakoids and photosystem biogenesis (vesicular trafficking, provision of material for thylakoid biosynthesis, photosystems assembly) and the loss of the plastid division machinery. Altogether, the data provide new insights on the chromoplast differentiation process while enriching our knowledge of the plant plastid proteome

Early anther ablation triggers parthenocarpic fruit development in tomato

[EN] Fruit set and fruit development in tomato is largely affected by changes in environmental conditions, therefore autonomous fruit set independent of fertilization is a highly desirable trait in tomato. Here, we report the production and characterization of male-sterile transgenic plants that produce parthenocarpic fruits in two tomato cultivars (Micro-Tom and Moneymaker). We generated male-sterility using the cytotoxic gene barnase targeted to the anthers with the PsEND1 anther-specific promoter. The ovaries of these plants grew in the absence of fertilization producing seedless, parthenocarpic fruits. Early anther ablation is essential to trigger the developing of the transgenic ovaries into fruits, in the absence of the signals usually generated during pollination and fertilization. Ovaries are fully functional and can be manually pollinated to obtain seeds. The transgenic plants obtained in the commercial cultivar Moneymaker show that the parthenocarpic development of the fruit does not have negative consequences in fruit quality. Throughout metabolomic analyses of the tomato fruits, we have identified two elite lines which showed increased levels of several health promoting metabolites and volatile compounds. Thus, early anther ablation can be considered a useful tool to promote fruit set and to obtain seedless and good quality fruits in tomato plants. These plants are also useful parental lines to be used in hybrid breeding approaches.This work was supported by grants from the Spanish Ministerio de Ciencia e Innovacion (MICINN, AGL2009-07617 to M.M.) and the Ramon y Cajal Program (RYC-2007-00627 to C.G.-M.). We thank Teresa Caballero, Aurora Medina, Rosa Rodriguez and Jose Luis Rambla for technical assistance with metabolomic analysis and Rafael Martinez for expert plant care.Medina Herranz, M.; Roque Mesa, EM.; Pineda Chaza, BJ.; Cañas Clemente, LA.; Rodríguez-Concepción, M.; Beltran Porter, JP.; Gómez Mena, MC. (2013). Early anther ablation triggers parthenocarpic fruit development in tomato. Plant Biotechnology Journal. 11(6):770-779. https://doi.org/10.1111/pbi.12069S77077911

Enhanced flux through the methylerythritol 4-phosphate pathway in Arabidopsis plants overexpressing deoxyxylulose 5-phosphate reductoisomerase

The methylerythritol 4-phosphate (MEP) pathway synthesizes the precursors for an astonishing diversity of plastid isoprenoids, including the major photosynthetic pigments chlorophylls and carotenoids. Since the identification of the first two enzymes of the pathway, deoxyxylulose 5-phoshate (DXP) synthase (DXS) and DXP reductoisomerase (DXR), they both were proposed as potential control points. Increased DXS activity has been shown to up-regulate the production of plastid isoprenoids in all systems tested, but the relative contribution of DXR to the supply of isoprenoid precursors is less clear. In this work, we have generated transgenic Arabidopsis thaliana plants with altered DXS and DXR enzyme levels, as estimated from their resistance to clomazone and fosmidomycin, respectively. The down-regulation of DXR resulted in variegation, reduced pigmentation and defects in chloroplast development, whereas DXR-overexpressing lines showed an increased accumulation of MEP- derived plastid isoprenoids such as chlorophylls, carotenoids, and taxadiene in transgenic plants engineered to produce this non-native isoprenoid. Changes in DXR levels in transgenic plants did not result in changes in␣DXS gene expression or enzyme accumulation, confirming that the observed effects on plastid isoprenoid levels in DXR-overexpressing lines were not an indirect consequence of altering DXS levels. The results indicate that the biosynthesis of MEP (the first committed intermediate of the pathway) limits the production of downstream isoprenoids in Arabidopsis chloroplasts, supporting a role for DXR in the control of the metabolic flux through the MEP pathway.This work was supported by grants from the Spanish Ministerio de Ciencia y Tecnología and FEDER to MRC (BIO2002-1653 and BIO2005-00367) and AB (BMC2003-06833). AC, PB-P, and OB received doctoral fellowships from the Spanish Ministerio de Educación y Ciencia.Peer reviewe

Plastid Cues Posttranscriptionally Regulate the Accumulation of Key Enzymes of the Methylerythritol Phosphate Pathway in Arabidopsis

Plastid isoprenoids (including hormones and photosynthetic pigments) are essential for plant growth and development, but relatively little is known of how the production of their metabolic precursors via the recently elucidated methylerythritol phosphate (MEP) pathway is regulated. We have identified an Arabidopsis (Arabidopsis thaliana) mutant that survives an otherwise lethal block of the MEP pathway with fosmidomycin (FSM). In rif10 (resistant to inhibition with FSM 10) plants, the accumulation of flux-controlling enzymes of the pathway is posttranscriptionally up-regulated. Strikingly, this phenotype is linked to a lower accumulation of plastidial isoprenoid pigments such as chlorophylls and carotenoids, resulting in mutant plants that are paler and smaller than the wild type. The rif10 mutant is impaired in plastid RNA processing due to a T-DNA insertion in the coding region of the At3g03710 gene encoding the chloroplast-targeted exoribonuclease polyribonucleotide phosphorylase. FSM resistance and other rif10-like phenotypes were also observed in wild-type Arabidopsis, tomato (Lycopersicon esculentum), and rice (Oryza sativa) seedlings grown in the presence of sublethal concentrations of chloramphenicol (an inhibitor of protein synthesis in plastids). By contrast, treatment with norflurazon (an inhibitor of carotenoid biosynthesis causing a similar pale cotyledon phenotype) did not result in FSM resistance. Together, the results support that plastome-encoded proteins are involved in negatively regulating the posttranscriptional accumulation of specific nuclear-encoded MEP pathway enzymes in chloroplasts. Regulation of the MEP pathway by a mechanism dependent on plastid cues might function under physiological conditions to finely adjust plastidial isoprenoid biosynthesis to the metabolic capabilities or requirements of plastids