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In this study the main purpose has been to evidence the importance of Physical Education in Early Childhood Learning as a source of research in education from the perspective of neuroscience. Students, when initiating the process of education and learning, are in a constant training and building of knowledge. In this way, Physical Education contributes to the process of research in education: as evidence of social and ethical personal development, and addressing the holistic education of children in physical, cognitive, emotional and social aspects. With this approach, Physical Education is related directly to the perspective of neuroscience, by means of recreational activities and actions of daily movements that are based on the basic concepts necessary for living.

Los carotenoides son metabolitos isoprenoides de gran relevancia económica como pigmentos naturales y fitonutrientes. Durante la maduración del fruto de tomate (Solanum lycopersicum) se acumulan niveles elevados de carotenoides como β-caroteno (naranja) y licopeno (rojo) en un tipo de plasto especializado denominado cromoplasto. En la maduración se pueden distinguir tres estadios según el color del fruto: Verde Maduro (VM), Naranja (N) y Rojo (R). La transición de VM a N y por último a R, se caracteriza por una fuerte inducción en la acumulación de los niveles de carotenoides y, por ende, la diferenciación de cloroplastos en cromoplastos. La acumulación global de carotenoides depende de la actividad de enzimas biosintéticas como PSY. En el fruto de tomate, la actividad PSY procede fundamentalmente de la isoforma PSY1. Durante esta tesis se ha demostrado que el gen PSY1 es una diana directa de un factor de transcripción regulado por luz denominado PIF1a, que se une al promotor del gen para reprimir su expresión. En concordancia, frutos de tomate con niveles reducidos de PIF1a mostraron una mayor expresión de PSY1 y por tanto una mayor acumulación de carotenoides. Además, hemos establecido un mecanismo molecular basado en la regulación de la estabilidad por luz de PIF1a que permite ajustar la síntesis de carotenoides al estado real de maduración del fruto. En la segunda parte de la tesis se ha explorado la relevancia del complejo de la Clp proteasa plastídica en la regulación de los niveles de proteínas implicadas en el metabolismo de carotenoides y en el almacenamiento de estos pigmentos en el fruto de tomate. La disminución de dicha actividad proteolítica mediante silenciamiento génico, generó frutos transgénicos enriquecidos en β-caroteno (pro-vitamina A). Más aún, la caracterización de dichos frutos mediante TEM y microscopía Raman sirvió como plataforma para establecer la importancia de dicho complejo proteolítico durante la diferenciación de cloroplastos en cromoplastos. Finalmente, estudios en el campo de la proteómica cuantitativa ayudaron a la elucidación de posibles nuevas proteínas diana de dicha proteasa, incluyendo PSY1., Carotenoids are isoprenoid metabolites of great economic importance as natural pigments and phytonutrients. Carotenoids such as lycopene (red) and β-carotene (orange) accumulate at high levels in a type of specialized plastid called chromoplast during tomato (Solanum lycopersicum) fruit ripening. Three different ripening stages can be distinguished according to the color of the fruit: Mature Green (MG), Orange (O) and Red/Ripe (R). The transition from MG to O, and finally to R, is characterized by a strong induction in the levels of carotenoids and therefore, the differentiation of chloroplasts into chromoplasts. The global accumulation of carotenoids depends on the activity of biosynthetic enzymes such as PSY. In tomato fruit, PSY activity is mainly provided by the PSY1 isoform. During this thesis it has been demonstrated that the PSY1 gene is a direct target of a light-regulated transcriptional factor named PIF1a, which binds to the gene promoter to repress its expression. In agreement, tomato fruits with reduced levels of PIF1a show higher PSY1 transcript levels and hence an enhanced accumulation of carotenoids. Additionally, we have established a molecular mechanism based on the regulation of PIF1a photostability, that allos to adjust carotenoid biosynthesis to the actual fruit ripening stage. In the second part of the thesis we have explored the revelance of the plastidial Clp protease complex for the regulation of the turnover of proteins involved in carotenoid metabolism and storage in tomato fruit. Successful reduction of Clp protease activity using gene silencing approaches generated transgenic fruits enriched in β-carotene (pro-vitamin A). In addition, the characterization of these fruits by TEM and Raman imaging helped us to establish the relevance of this proteolytic complex for chromoplast development. Finally, quantitative proteomic studies served to elucidate potential Clp protease targets in chromoplasts, including PSY1.

Profound metabolic and structural changes are required for fleshy green fruits to ripen and become colorful and tasty. In tomato (Solanum lycopersicum), fruit ripening involves the differentiation of chromoplasts, specialized plastids that accumulate carotenoid pigments such as β-carotene (pro-vitamin A) and lycopene. Here, we explored the role of the plastidial Clp protease in chromoplast development and carotenoid accumulation. Ripening-specific silencing of one of the subunits of the Clp proteolytic complex resulted in β-carotene-enriched fruits that appeared orange instead of red when ripe. Clp-defective fruit displayed aberrant chromoplasts and up-regulated expression of nuclear genes encoding the tomato homologs of Orange (OR) and ClpB3 chaperones, most probably to deal with misfolded and aggregated proteins that could not be degraded by the Clp protease. ClpB3 and OR chaperones protect the carotenoid biosynthetic enzymes deoxyxylulose 5-phosphate synthase and phytoene synthase, respectively, from degradation, whereas OR chaperones additionally promote chromoplast differentiation by preventing the degradation of carotenoids such as β-carotene. We conclude that the Clp protease contributes to the differentiation of chloroplasts into chromoplasts during tomato fruit ripening, acting in co-ordination with specific chaperones that alleviate protein folding stress, promote enzyme stability and accumulation, and prevent carotenoid degradation