Effects of overexpression of mitochondrial uncoupling protein (UCP1) on response to abiotic stress and photosynthetic metabolism in maize (Zea mays)

• Grant number: 17/15229-4
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: November 01, 2017
• End date: September 30, 2020
• Field of knowledge: Biological Sciences - Genetics - Plant Genetics
• Principal Investigator: Paulo Arruda
• Grantee: Vinícius de Oliveira Almeida
• Host Institution: Centro de Biologia Molecular e Engenharia Genética (CBMEG). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

The exposure of plants to environmental stresses induces the production of Reactive Oxygen Species (ROS). In eukaryotic cells the Electron Transport Chain (ETC) located on the inner membrane of the mitochondria is the largest source of ROS. Uncoupling Mitochondrial Protein 1 (UCP1) is also located in the internal mitochondrial membrane, where it dissipates the membrane potential between the intermembrane space and the mitochondrial matrix, independent of the production of ATP. In this way, the ETC electron flux is stimulated and ROS production is reduced. Plants of Nicotiana tabacum overexpressing the UCP1 of Arabidopsis thaliana (AtUCP1) present high tolerance to water and saline stress when compared to wild plants. In addition, these plants have an increase in stomatal conductance and photosynthetic rate under normal conditions or under abiotic stress. Overexpression of AtUCP1 leads to important metabolic changes associated with the beneficial effects observed when plants undergo stress. These plants have high mitochondrial biogenesis that, through mitochondrial-nucleus signaling, induces the expression of hundreds of nuclear and mitochondrial genes, associated with stress responses. Due to the effects of resistance to abiotic stress observed in the model plants, we propose in this project to study the effect of UCP1 overexpression of sorghum (Sorghum bicolor) on corn, one of the main agricultural crops in the world, evaluating its productivity under conditions of water stress. In addition, as the model plants in which studies of UCP1 was carried out show C3 photosynthetic metabolism, the study of UCP1 in maize would provide new information regarding the function of this protein in plants of C4 metabolism. (AU)