Browsing by Author "Tapia, Rodrigo"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    A Deficiency in the Flavoprotein of Arabidopsis Mitochondrial Complex II Results in Elevated Photosynthesis and Better Growth in Nitrogen-Limiting Conditions
    (AMER SOC PLANT BIOLOGISTS, 2011) Fuentes, Daniela; Meneses, Marco; Nunes Nesi, Adriano; Araujo, Wagner L.; Tapia, Rodrigo; Gomez, Isabel; Holuigue, Loreto; Gutierrez, Rodrigo A.; Fernie, Alisdair R.; Jordana, Xavier
    Mitochondrial complex II (succinate dehydrogenase [SDH]) plays roles both in the tricarboxylic acid cycle and the respiratory electron transport chain. In Arabidopsis (Arabidopsis thaliana), its flavoprotein subunit is encoded by two nuclear genes, SDH1-1 and SDH1-2. Here, we characterize heterozygous SDH1-1/sdh1-1 mutant plants displaying a 30% reduction in SDH activity as well as partially silenced plants obtained by RNA interference. We found that these plants displayed significantly higher CO2 assimilation rates and enhanced growth than wild-type plants. There was a strong correlation between CO2 assimilation and stomatal conductance, and both mutant and silenced plants displayed increased stomatal aperture and density. By contrast, no significant differences were found for dark respiration, chloroplastic electron transport rate, CO2 uptake at saturating concentrations of CO2, or biochemical parameters such as the maximum rates of carboxylation by Rubisco and of photosynthetic electron transport. Thus, photosynthesis is enhanced in SDH-deficient plants by a mechanism involving a specific effect on stomatal function that results in improved CO2 uptake. Metabolic and transcript profiling revealed that mild deficiency in SDH results in limited effects on metabolism and gene expression, and data suggest that decreases observed in the levels of some amino acids were due to a higher flux to proteins and other nitrogen-containing compounds to support increased growth. Strikingly, SDH1-1/sdh1-1 seedlings grew considerably better in nitrogen-limiting conditions. Thus, a subtle metabolic alteration may lead to changes in important functions such as stomatal function and nitrogen assimilation.
  • Thumbnail Image
    Item
    Actas Seminario Interdisciplina en la UC
    (2012) Flores, Luis; Haye, Andrés; Rebolledo, Rolando; Araos, Consuelo; Parra, Catalina de la; Rivera, Daniela; Vergara, Alejandro; San Martín, Ernesto; Min, Wonjung; Funk, regina; Onell, Roberto; Holmes, Robert; García Huidobro, Vicente; Cádiz, Rodrigo; Cuadra, Patricio de la; Sylleros, Álvaro; Hermosilla, Katherine; Vega, Patricia; Ibarra, Macarena; Ramírez, Cecilia; Bonomo, Umberto; Torres, Marisa; Tapia, Rodrigo; Cottet, Pablo; Rojas Lasch, Carolina; Haye M., Andrés
    Publicación de trabajos derivados de un seminario realizado el 14 de diciembre de 2011, patrocinado por la Vicerrectoría de Investigación, la Facultad de Ciencias Sociales y Facultad de Filosofía, con el fin de reunir y poner en diálogo diversas experiencias de interdisciplina en la universidad y así favorecer su reconocimiento como estrategia de conocimiento, reflexionar sus limitaciones y potenciar su crecimiento. Editores: Carolina Rojas y Andrés Haye. Producción y diseño: Laboratorio de Hipermedios, Facultad de Letras PUC, Pablo Chiuminatto, Rodrigo del Río. Corrección de textos: Loreto Fernández. Organización del Seminario: Carolina Rojas, Andrés Haye, Patricio Miranda, Pablo Herraz, Gabriela Rubilar.
  • Thumbnail Image
    Item
    Novel Avulaviruses in Penguins, Antarctica
    (2017) Neira, Víctor; Tapia, Rodrigo; Verdugo, Claudio; Barriga, Gonzalo; Mor, Sunil; Fei Fan Ng, Terry; García, Victoria; Del Río, José; Rodríguez, Pedro; Medina, Rafael; Briceño, Cristóbal; González Acuña, Daniel