SUMO proteases implement regulatory logic across Hormonal Networks to enact Plant Stress Responses

Plants rely on precisely regulated hormonal networks to balance defence and growth during stress. In this context, the SUMO proteases that govern deSUMOylation have emerged as the critical regulatory system. In this review, we outline how SUMO proteases modulate stress response by selectively deSUMOylating key components of hormone biosynthesis, perception and signalling across major phytohormonal pathways, such as Jasmonic acid (JA), Salicylic acid (SA), abscisic acid (ABA), gibberellin (GA), auxin and brassinosteroid (BR). We highlight the role of closely related SUMO proteases subsets such as OTS1/OTS2, SPF1/SPF2 and ESD4/ELS1 in reprogramming hormonal hierarchies to fine-tune defence outputs. Additionally, we illustrate that distinct SUMO protease subsets operate in a cell-type-specific manner, to coordinate hormonal pathways. Overall, our findings position SUMO proteases as dynamic modulators that translate environmental cues into balanced hormonal outputs. Despite the recent progress, the substrate specificity, interaction dynamics and spatiotemporal regulation of these proteases are open areas for further exploration. Understanding how SUMO proteases reshape hormonal networks will unravel novel strategies to generate climate resilient crops.