Indeterminate growth of plant body relies on the activity of apical meristems in which behavior of stem cells is regulated by local hormonal signals. To understand the evolution of plant stem cell signaling system, we are studying CLE (CLV3/ESR-related) peptide signaling in the liverwort Marchantia polymorpha. We found that the single CLV3 ortholog, MpCLE2, promotes the expansion of the stem cell zone in the meristem of M. polymorpha gametophyte, which can induce supernumerary branching from the meristem (Hirakawa et al 2020). The stem cell-promoting activity of MpCLE2 is contrary to the conventional stem cell-limiting CLV3/CLE signaling in A. thaliana. Since a CLE gene with similar function, AtCLE40, was reported by Schlegel et al. 2021, it is conceivable that stem cell-promoting CLE peptide signaling is an ancestral pathway conserved throughout land plants (Hirakawa 2022). Instead, a stem cell-limiting CLV3 pathway in flowering plants may be a derived condition evolving after gene duplication in the common ancestor of flowering plants. To identify the downstream targets of MpCLE2 signaling, we conducted RNA-seq analysis using gain-of-function and loss-of-function alleles for MpCLE2 and its receptors (Takahashi et al. 2023). Gene expression analysis of the DETFs show that they are expressed in the meristem. Functional analysis suggests that they are involved in regulation of the cell division orientation or cell identity. These genes may represent evolutionarily conserved regulators in plant meristem development.