Research

An opinion paper about the evolution of CLE peptide signaling. This paper proposes that stem-cell-promoting CLE peptide signaling, such as Marchantia MpCLE2 and Arabidopsis CLE40, may be a conserved  mechanism in the shoot apical meristems in gametophyte and sporophyte generations of land plants. In contrast, canonical Arabidopsis CLV3 signaling may be a derived condition evolving after gene duplication in the flowering plant lineage.

Evolution of meristem zonation by CLE gene duplication in land plants | Nat Plants (featured on the cover)

Marchantia has a single homolog of Arabidopsis CIK/CLERK/NIK coreceptors. The Marchantia gene, MpCIK, is essential for MpCLE2 signaling in meristem and gemma cup development. Thus, the ligand-receptor pairs seem broadly conserved in land plants.

An Evolutionarily Conserved Coreceptor Gene Is Essential for CLAVATA Signaling in Marchantia polymorpha | FIPS

This study shows MpCLE2 is a positive regulator of the stem cell population size in the shoot apical meristem of Marchantia gametophyte. Supernumerary branching can be induced by MpCLE2 peptide treatment. The function of MpCLE2 is opposite to that of CLV3 in the shoot apical meristem of Arabidopsis sporophyte.

Induction of Multichotomous Branching by CLAVATA Peptide in Marchantia polymorpha | Curr Biol

Marchantia has two CLE genes, MpCLE1 and MpCLE2. This study shows MpCLE1, the close homolog of Arabidopsis TDIF/CLE41/CLE44, acts as a negative regulator of cell proliferation in the shoot apical meristem of Marchantia gametophyte.

Control of proliferation in the haploid meristem by CLE peptide signaling in Marchantia polymorpha | PLOS Genet