Journal Article

BAM 1 and RECEPTOR ‐ LIKE PROTEIN KINASE 2 constitute a signaling pathway and modulate CLE peptide‐triggered growth inhibition in A rabidopsis root

Yamada, Masashi, Hasebe, Mitsuyasu, Yamaguchi, Katsushi, Shimizu, Noriko, Shigenobu, Shuji, Ishida, Takashi, Tabata, Ryo, Kinoshita, Atsuko, Mitsumasu, Kanako, Sawa, Shinichiro

2015

Overview

Ligand receptor‐based signaling is a means of cell‐to‐cell communication for coordinating developmental and physiological processes in multicellular organisms. In plants, cell‐producing meristems utilize this signaling to regulate their activities and ensure for proper development. Shoot and root systems share common requirements for carrying out this process; however, its molecular basis is largely unclear. It has been suggested that synthetic CLV 3/ EMBRYO SURROUNDING REGION ( CLE ) peptide shrinks the root meristem through the actions of CLAVATA 2 ( CLV 2 ) and the RECEPTOR ‐ LIKE PROTEIN KINASE 2 ( RPK 2 ) pathway in Arabidopsis thaliana . Our genetic screening for mutations that resist CLE peptide signaling in roots determined that BAM 1, which is a member of the leucine‐rich repeat receptor‐like kinase ( LRR ‐ RLK ) family, is also involved in this pathway. BAM 1 is preferentially expressed in the root tip, including the quiescent center and its surrounding stem cells. Our genetic analysis revealed that BAM 1 functions together with RPK 2. Using coimmunoprecipitation assay, we showed that BAM 1 is capable of forming heteromeric complexes with RPK 2. These findings suggest that the BAM 1 and RPK 2 receptors constitute a signaling pathway that modulates cell proliferation in the root meristem and that related molecules are employed in root and shoot meristems.