Session 8 - Deciphering the SUMO code for adaptive responses in plants

Post-translational modification (PTM) events generate proteoforms that orchestrate cell signalling in almost every biological process. The SUMOcode project aims to understand a critically important but understudied PTM in plants, SUMO (Small Ubiquitin-like Modifier). The rules governing specificity and function remain rudimentary for most PTMs, but the plant SUMO system provides a unique possibility to unravel the rules governing SUMOylation, as its core machinery comprises only 33 genes in Arabidopsis, compared with many hundreds for other PTMs.Our central hypothesis is that SUMO specificity is conferred through how cells are primed to respond to different stress signals, the tissue and cellular spatial distribution of SUMO machinery and substrates and control of SUMOylation modification via activation, repression and competition for PTM sites.We have developed a SUMO system cell atlas (a resource that will characterize each part of the machinery), how and in which cells and when it works, so that a map of the key events that trigger a SUMOylation response to environmental cues can be revealed.