Defining the role of the heterodimerization network involving the transcription regulatory factors bZIP1, bZIP53 and bZIP63 in the control of energy homeostasis focusing on starch degradation

Abstract

Plants, as sessile organisms, have developed sophisticated mechanisms for optimizing the balanced use of energy sources in response to changes in the environment. During the day, carbohydrates such as sucrose and starch (reserve polymer), resulting from CO2 fixation through photosynthesis, represent the main source of energy used by plants to carry out their vital functions. At night, starch is degraded at a rate compatible with a regular supply of carbohydrates to sustain growth until dawn. The regulation of this process involves the clock circadian. In Arabidopsis thaliana, the programmed degradation of starch includes the transcription regulator bZIP type, AtbZIP63 (bZIP63). bZIP63 works with its heterodimerization partners bZIP1 and bZIP53. However, the importance of heterodimers in controlling of starch metabolism is still unknown. The main objective of the doctorate is to understand the role of transcriptional regulation factors bZIP1, 53 and 63 in the diel control of energy resources. Thus, the work should bring unpublished information about the interface between the circadian clock and sugar signaling in maintaining homeostasis with a focus on controlling starch degradation. (AU)