Assessing the role of the transcription factor AtbZIP63 in Arabidopsis thaliana resistance to Pseudomonas syringae pv. tomato strain DC3000

• Grant number: 13/07295-6
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Effective date (Start): August 01, 2013
• Effective date (End): July 31, 2014
• Field of knowledge: Biological Sciences - Genetics - Plant Genetics
• Principal Investigator: Michel Georges Albert Vincentz
• Grantee: Cleverson Carlos Matiolli
• Supervisor: Maeli Melotto
• Host Institution: Centro de Biologia Molecular e Engenharia Genética (CBMEG). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Research place: University of Texas at Arlington (UT Arlington), United States
• Associated to the scholarship: 12/09351-8 - Protein stability evaluation of transcription factor AtbZIP63 in biotic/abiotic stress responses and the role of this gene in resistance of Arabidopsis thaliana to Pseudomonas syringae pv tomato strain DC3000, BP.PD

Abstract

In the model plant Arabidopsis thaliana, the accumulation of transcription factor AtbZIP63 mRNA is regulated daily fluctuation levels of sugars, abscisic acid (ABA), circadian clock and pathogen infection. Accordingly, the functional classification of the 280 genes misregulated in the T-DNA insertion mutant atbzip63-1 suggests that AtbZIP63 is directly or indirectly involved in the regulation of genes related to energy stress, abiotic and biotic stresses, probably modulating energy usage in response to environmental challenges. Preliminary studies performed in collaboration with the researcher Maeli Melotto (University of Texas at Arlington - UTA) showed that the mutant atbzip63-1 is more resistant than their respective wild genotype Columbia to infection by the pathogen Pseudomonas syringae pv. tomato (Pst) strain DC3000. Additionally, ongoing research in our laboratory suggest the participation of AtbZIP63 also in control of starch mobilization during the night, suggesting a possible relationship between energy status and resistance to pathogens mediated at least partially by AtbZIP63. However, the molecular mechanisms associated with the resistance of the mutant atbzip63-1 to Pst DC3000 remains unknown. This research project aims to elucidate the molecular mechanisms by which AtbZIP63 operates in plant defense against Pst DC3000 as well as to evaluate the susceptibility of AtbZIP63 overexpressors and RNAi knockdown genotypes in order to validate the results previously obtained with atbzip63-1 mutant. The interaction of AtbZIP63 protein with key proteins involved in responses to infection by Pst DC3000, especially those that participate in the JA-Ile (Jasmonate-Isoleucine conjugate) signaling pathways, will be evaluated by Y2H (Yeast two-hybrid). Furthermore, the mRNA profiles of the mutant atbzip63-1 and their respective Col-0 wild type will be compared during the course of infection with Pst DC3000. These analysis will provide new clues about AtbZIP63 role in pathogen resistance in the model plant Arabidopsis thaliana and the possible relationship between energy status and biotic stress resistance. (AU)