The SCOOP family of phytocytokines, at the boundaries of plant defense and development

Abstract

The identification of a new family of phytocytokines, named SCOOP for serine-rich endOgenOus peptides, in 2019 [1] has reached important studies in the field of plant molecular biology conducted in recent years. They have highlighted the fact that the SCOOP peptides are actually a major family of signal peptides of Arabidopsis, being involved in biotic stress responses, through their recognition by a specific receptor complex [2, 3]. In addition, we have shown that some members could be involved in the regulation of various developmental processes such as the control of root development or flowering transition [4, 5]. Recently, MS/MS analysis of leaf apoplastic fluids enabled us to identify two different SCOOP10 peptides encoded by the same PROSCOOP10 precursor which validated for the first time the biological reality of our bioinformatic predictions. However, this family still raises new questions about the regulatory mechanisms of its signaling pathways and the processing of precursors coming from such a diverse gene family that we will discuss. Eventually this family of phytocytokines, being at the frontier of defense and development pathways, opens up new prospects for breeding strategies taking these two aspects into account together.