2021 年 56 巻 2 号 p. 85-91
Growth and organogenesis in plants is sustained by pluripotent stem cells. Small endogenous peptides encoded by the CLAVATA3/EMBRYO SURROUNDING REGION-related (CLE) genes were originally identified as a regulator of stem cell activities in Arabidopsis thaliana. Subsequent studies in monocot and dicot model plants uncovered various developmental and physiological roles of CLEs as well as their involvement in cross-species communication. Homologues of CLEs and their receptors are widely conserved across land plant lineages. Over the last few years, functional and comparative genomic studies on non-flowering plant CLEs have accumulated and started to shed light on how CLE signalingsystems evolved. This review aims to serve as a primer on our growing understanding as well as outstanding questions about CLE signaling systems from an evolutionary perspective.