As climate change progresses, flooding events have become more frequent and intense. Flooding subjects plant roots to hypoxic (low oxygen) conditions, hindering gas exchange and leading to the accumulation of ethylene (volatile plant hormone), making this an important flood detection cue. Plant plasticity is especially important for plants in order to survive sub-optimal and stress conditions. Meristematic cells are key players in this because they are undifferentiated cells found at shoot and root tips with the potential to generate organs. The mechanisms behind meristem tolerance to stress conditions have yet remained underexplored. Previous experiments have shown that, in Arabidopsis, an ethylene pre-treatment following subsequent hypoxic stress can enhance root survival. While it is clear that the activating mechanism caused by ethylene accumulation boosts the regrowth capacity of roots after hypoxia, it is yet unknown how meristem protection is conferred. Is ethylene mediated by specific cell layers in the root? Do specific cell layers communicate signals in order to coordinate meristem protection?
My project focuses on elucidating the role of ethylene in conferring meristematic protection and to understand where exactly this is carried out in the root. For this, I use cell-type specific lines that have a disruption in ethylene signaling, and through imitating flooding conditions, study the survival effect on root tips. This is coupled with other reporter lines in order to be able to further understand what other players are involved in this meristematic protection during flooding conditions.