Joaquín Medina Alcázar
At present our group is focused on understanding the plant mechanisms to adjust metabolism to survive abiotic stresses (dehydration and nutrient deficiencies). The susceptibility or tolerance to these kinds of abiotic stress is a complex phenomenon since it happens at different developmental stages, and often different types of stress take place at the same time. In order to identify key regulatory genes involved in metabolic adjustment in Arabidopsis, and to transfer this knowledge into practical breeding of crop and tree models, we have used both genetic and system biology approaches. Thus, we have identified several mutations that alter plant tolerance and studied different probabilistic models that describe the Arabidopsis regulatory network. The models are built with different types of data such as coexpression, protein-protein interaction, transcription factor binding sites, etc. The analyses of the models allowed us to discover several genes that might be involved in the metabolic adjustment, particularly the identified transcription factors belonging to the DOF, bZIP, NAC, bHLH, MYB gene families. Molecular and genetic analyses indicated that some of them play an important role in plant responses to abiotic stresses.
We are interested in the study of plant responses to abiotic stresses, such us dehydration and nutrient deficiency, mainly nitrogen and Sulphur, and how plants adjust their metabolism in order to survive combinations of these conditions. We use Systems Biology approaches, and as experimental models plants such as Arabidopsis and tomato and plant species adapted to extreme conditions, such as those living in the Atacama Desert. Identification and characterization of relevant genes that play roles in plant abiotic responses will be useful for breeding programmes.
Determination of the molecular mechanisms and general strategies of Arabidopsis plants involved in the response to dehydration and nutrient deficiency (Nitrogen and Sulphur).
Study of the connection between Arabidopsis signaling pathways and responses to drought and nutrient limitation; identification and molecular characterization of Regulatory Factors involved in both Plant responses.
- Establishment of new methods to construct and analyse regulatory networks that describe abiotic stress responses in Arabidopsis and tomato
- Study abiotic stress resistance mechanisms and resistant genes in extremophile organisms
Developing new approaches to obtain more tolerant varieties to stress-conditions such as water deficit and nutritional limitation.
Seed Bio-fortification. Optimization of seed nutrient content: proteins, vitamins and macro-micronutrients
Obtaining improved varieties for organic farming
Techniques of massive plant phenotyping, Genetic mapping, QTLs analysis and selection of candidate genes
2013-2017. INIA Grant (INIA number RTA2012-0008-CO2).Using transcription factors as a tool to increase biomass production and abiotic stress tolerance in solanaceae. PI. Joaquín Medina.
2016-2017. Internationalization Program PUC, (Pontificia Universidad Católica de Chile). New strategies for the improvement of crops under conditions of climate change: Identification of new genes involved in the assimilation of micro-nutrients. IPs. Hannetz Roschzttardtz, Xavier Jordana, Jesus Vicente-Carbajosa, Joaquin Medina.
2015-2017. Explora Call. MICIN. Increase in energy and carbon capture in plant systems. Jesus Vicente-Carbajosa, Joaquin Medina.
2012-2015. Inspire Call; REPSOL. Optisol: Optimized lignocellulose exploitation from solanacae canopy. IPs Stephan Pollmann, Jesus Vicente Carbajosa, Julia Kehr, Joaquin Medina.
2009-2012. INIA Grant. (INIA RTA2009-00042-CO2-01). Development of new strategies for the improvement of resistance to abiotic stress conditions in tomato. PI Joaquin Medina.
Corrales, Alba-Rocio ; Carrillo, Laura; Lasierra-Resa, Pilar; G. Nebauer, Sergio; Dominguez-Figueroa, José; Renau-Morata, Begoña; Pollmann, Stephan; Granell, Antonio; Molina, Rosa V; Vicente-Carbajosa, Jesús; Medina, Joaquín. Multifaceted Role of Cycling Dof Factor 3 (CDF3) in the regulation of flowering time and abiotic stress responses in Arabidopsis. Plant, Cell and Environment (2016). In press.
Hossain A, Henriquez-Valencia C, Gomez-Paez M, Orellana A, Vicente-Carbajosa J, Medina J, Zouhar J. Identification of novel components of the unfolded protein response in Arabidopsis. Frontiers Plant Science (2016) http://dx.doi.org/0.3389/fpls. 2016.0065
- Massimiliano Zanin, Joaquín Medina Alcazar, Jesus Vicente Carbajosa, Marcela Gomez Paez David Papo, Pedro Sousa Ernestina Menasalvas, and Stefano Boccaletti. Parenclitic networks: uncovering new functions in biological data. Science reports (2014); 4: 5112. doi: 10.1038/srep05112.
- Alba Rocio Corrales, Sergio G. Nebauer, Laura Carrillo, Pedro Fernandez-Nohales, Jorge Marques, Begona Renau-Morata, Antonio Granell, Stephan Pollmann, Jesus Vicente-Carbajosa, Rosa-Victoria Molina, Joaquin Medina. Characterization of tomato Cycling Dof Factors reveals conserved and new functions in the control of flowering time and abiotic stress responses. Journal of Experimental Botany (2014). doi: 10.1093/jxb/ert451
- Alba Rocío Corrales, Laura Carrillo, Sergio G Nebauer, Pedro Fernández-Nohales, Jorge Marqués, Begoña Renau-Morata, Antonio Granell, Stephan Pollmann, Jesús Vicente-Carbajosa, Rosa Victoria Molina and Joaquín Medina. Salinity Assay in Arabidopsis Bio-protocol (2014) 4(16): e1216.
- Hentrich M, Sánchez-Parra B, Pérez Alonso MM, Carrasco Loba V, Carrillo L, Vicente-Carbajosa J, Medina J, Pollmann S. YUCCA8 and YUCCA9 overexpression reveals a link between auxin signaling and lignification through the induction of ethylene biosynthesis. Plant Signal Behav. 2013 Sep 10;8(11). doi:pii: e26363
- Hentrich, Mathias; Böttcher, Christine; Düchting, Petra; Cheng,Youfa; Zhao, Yunde;Berkowitz, Oliver; Masle, Josette; Medina, Joaquín; Pollmann, Stephan. The jasmonic acid signaling pathway is linked to auxin homeostasis through the regulation of YUCCA8 and YUCCA9 gene expression. Plant Journal (2013) May; 74 (4):626-37.
- Fernando Novillo, Joaquin Medina, Marta Rodriguez-Franco, Gunther Neuhaus and Julio Salinas. Genetic analysis reveals a complex regulatory network modulating CBFs expression and Arabidopsis response to abiotic stress. Journal Experimental Botany (2012) Jan; 63 (1):293-304.
- Catala R, Medina J, and Julio Salinas. HY5 integrates low temperature and light signalling pathways. Proc. Nac. Acad. Sci. PNAS (2011) Sep 27; 108 (39):16475-80.
- Medina J, Catala R and Julio Salinas.: The CBFs: Three Arabidopsis transcription factors to cold acclimate. Plant Science (2011) 180: 3-11.