Prolyl hydroxylase-dependent proteolysis enables the orthogonal hypoxia responses in plants

Vascular plants and metazoans use selective proteolysis to control responses to hypoxia, although through distinct biochemical mechanisms. The reason for this divergence is puzzling, since the molecular components necessary for both strategies are conserved. To explore the alternative scenario where plants and animals respond to hypoxia through the same mechanisms, we engineer a three-components system aimed to target proteins for degradation in an oxygen dependent manner in Arabidopsis thaliana. When used to control transcription, the synthetic system partially restores hypoxia responsiveness in oxygen-insensitive mutants. Additionally, we demonstrate its potential to regulate growth under flood-induced hypoxia. Our work highlights the use of synthetic biology to reprogramme signalling pathways, providing insights into the evolution of oxygen sensing and offering tools for crop improvement under stress conditions.