8 research outputs found

    Determination of Soluble Sugars in Arabidopsis thaliana Leaves by Anion Exchange Chromatography

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    Determination of soluble sugars is basic for the study of carbon metabolism in plants. Soluble sugar quantitation can be achieved by enzymatic methods implying different coupled reactions. Here we describe a simple method that allows rapid determination of the most abundant soluble sugars (glucose, fructose and sucrose) in Arabidopsis leaves by anion exchange chromatography. We have applied this method to study the levels of soluble sugars during the photoperiodic transition to flowering (Ortiz-Marchena et al., 2014).Espa√Īa, MINECO projects CSD2007-00057, BIO2008-02292, and BIO2011-28847-C02-00Espa√Īa, Junta de Andaluc√≠a P06-CVI-01450 and P08-AGR-0358

    Purification of Starch Granules from Arabidopsis Leaves and Determination of Granule-Bound Starch Synthase Activity

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    Starch constitutes the most important carbon reserve in plants and is composed of branched amylopectin and linear amylose. The latter is synthesized exclusively by the Granule-Bound Starch Synthase (GBSS, EC 2.4.1.21). Here we report a readily reproducible, specific and highly sensitive protocol, which includes the isolation of intact starch granules from Arabidopsis thaliana leaves and the subsequent determination of GBSS activity. We have applied this method to study GBSS activity in diurnal cycles in vegetative growth and during the photoperiodic transition to flowering in Arabidopsis (Tenorio et al., 2003; Ortiz-Marchena et al., 2014).Espa√Īa,MINECO CSD2007-00057, BIO2008-02292, and BIO2011-28847-C02-00Espa√Īa, Junta de Andaluc√≠a P06-CVI-01450 and P08-AGR-0358

    Estudio comparativo, prote√≥mico y transcript√≥mico de la respuesta a az√ļcares de FRIGIDA en Arabidopsis thaliana.

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    Para maximizar su eficiencia reproductiva, las plantas deben florecer en un per√≠odo en el que se garanticen las condiciones √≥ptimas para la supervivencia de su descendencia. Por ello, las plantas captan se√Īales del entorno, principalmente temperatura y el n√ļmero de horas de luz recibidas. La floraci√≥n es un proceso complejo que implica cambios gen√©ticos, fisiol√≥gicos y metab√≥licos. Conocer los mecanismos por los que las plantas florecen tendr√≠a m√ļltiples aplicaciones biotecnol√≥gicas que podr√≠an paliar los efectos del cambio global sobre las cosechas. En Arabidopsis thaliana, existen 3 grandes v√≠as de regulaci√≥n de la floraci√≥n interconectadas entre s√≠, la v√≠a del fotoperiodo, la v√≠a aut√≥noma y la v√≠a de respuesta a la vernalizaci√≥n (Bl√°zquez et al., 2011). ¬†FRIGIDA (FRI) es una prote√≠na de 609 amino √°cidos codificada por una gen perteneciente a una familia g√©nica reducida. En Arabidopsis se han descrito numerosos ecotipos asociados a diferentes latitudes en los que FRI presenta¬† variaciones al√©licas asociadas a diferencias en el tiempo de floraci√≥n (Johanson et al., 2000). FRI induce la expresi√≥n de FLOWERING LOCUS C (FLC), un represor de la floraci√≥n, mediante un mecanismo epigen√©tico (Sung et al., 2004). Por otro lado, FRI act√ļa como una ‚Äúprote√≠na andamio‚ÄĚ interaccionando con reguladores espec√≠ficos de FLC como FRL1 (Frigida Like 1), FRL2 (FRIGIDA LIKE 2), FES1 (FRIGIDA ESENCIAL 1), SUF4 (SUPRESOR OF FRIGIDA) y FLX (FLC EXPRESSOR), formando el complejo FRI-C (FRI-Containing Complex) (Choi et al., 2011). ¬†Estudios previos han mostrado que FRI no s√≥lo act√ļa sobre FLC sino que tambi√©n reprimir√≠a la floraci√≥n a trav√©s MAF5 (Ribeiro, 2011). Tal y como ocurre con FLC, los niveles de transcrito de MAF5 oscilan a lo largo del d√≠a, mutaciones en la v√≠a del fotoperiodo y del reloj circadiano producen alteraciones en este patr√≥n de expresi√≥n (Fujiwara et al., 2010). La sacarosa, activador de la floraci√≥n, desempe√Īar√≠a un papel antag√≥nico estabilizando a la prote√≠na FRI a nivel postraduccional (Ribeiro, 2011), indicando una se√Īaliaci√≥n cruzada entre varias rutas de floraci√≥n.¬†En el presente trabajo, mediante estudios a nivel transcripcional y postraduccional, se analiza el efecto de diferentes az√ļcares sobre la expresi√≥n y estabilidad de FRI as√≠ como su comportamiento circadiano en la l√≠nea Sant feliu 2¬† (Sf2), resultante de la introgresi√≥n de un alelo activo de FRI en fondo gen√©tico Columbia (Col-0), y en la l√≠nea transg√©nica 35S:FRI::YFP (Col-0)

    CONSTANS‚ÄďFKBP12 interaction contributes to modulation of photoperiodic flowering in Arabidopsis

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    Flowering time is a key process in plant development. Photoperiodic signals play a crucial role in the floral transition in Arabidopsis thaliana, and the protein CONSTANS (CO) has a central regulatory function that is tightly regulated at the transcriptional and post-translational levels. The stability of CO protein depends on a light-driven proteasome process that optimizes its accumulation in the evening to promote the production of the florigen FLOWERING LOCUS T (FT) and induce seasonal flowering. To further investigate the post-translational regulation of CO protein we have dissected its interactome network employing in vivo and in vitro assays and molecular genetics approaches. The immunophilin FKBP12 has been identified in Arabidopsis as a CO interactor that regulates its accumulation and activity. FKBP12 and CO interact through the CCT domain, affecting the stability and function of CO. fkbp12 insertion mutants show a delay in flowering time, while FKBP12 overexpression accelerates flowering, and these phenotypes can be directly related to a change in accumulation of FT protein. The interaction is conserved between the Chlamydomonas algal orthologs CrCO‚ÄďCrFKBP12, revealing an ancient regulatory step in photoperiod regulation of plant development.Ministerio de Ciencia BIO2014-52425-P, BIO2017-83629-RJunta de Andaluc√≠a P08-AGR-03582, BIO-281European Union GA83831

    Evolution of the Flowering Pathways

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    Flowering plants are some of the most successful organisms on Earth, particularly those used in agriculture due to the widespread distribution produced by farming activities. The correct moment of the year to flower is a crucial decision as it strongly compromises the success of the progeny and is thus strictly controlled. Crops have been artificially selected to flower in those conditions better adapted for human production, and many genes related to flowering time are selected as targets for breeding programs. These characteristics reflect a complex regulatory pathway that has to respond both to predictable and unexpected changes in the environment. This plasticity confers the flowering plants with a genetic toolkit to adapt to varied habitats and changing environmental conditions. Recent advances in massive acquisition of data from many different species belonging to the green eukaryotic lineage allow us to make an evolutionary approach to the main mechanisms that influence the floral transition and how flowers are formed in modern plants. This work will review some of these aspects from the floral transition to the floral organogenesis

    I jornadas de intercambio de experiencias de educaci√≥n biling√ľe para alumnos y alumnas con discapacidad auditiva en Andaluc√≠a : comunicaciones y ponencias

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    Listado de centros participantes en las jornadas en las p√°ginas 150-151La promoci√≥n de medidas de atenci√≥n educativa personalizada e individualizada que satisfagan las necesidades educativas especiales del alumnado, especialmente de aquellas asociadas a discapacidad es una de las l√≠neas b√°sicas en la pol√≠tica de la Consejer√≠a de Educaci√≥n de la Junta de Andaluc√≠a. La eliminaci√≥n de todo tipo de barreras arquitect√≥nicas y comunicativas es una de las actuaciones que con mayor convencimiento se han impulsado en sucesivas legislaturas. Por este motivo, la promoci√≥n de experiencias biling√ľes para alumnos y alumnas sordos que requieran el uso de la lengua de signos espa√Īola fue uno de los programas que la Consejer√≠a incluy√≥ en el Plan de Acci√≥n Integral para las personas con discapacidad (2003-2006) con el objetivo de consolidar una oferta educativa cada vez m√°s completa y de mayor calidad.Andaluc√≠aInstituto Psicopedag√≥gico Dulce Nombre de Mar√≠a (M√°laga); Calle Manuel de Palacio, 17; 29017 M√°laga; +34902290499; [email protected]
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