%0 Generic
%A Holzwart, Eleonore
%D 2019
%F heidok:25681
%R 10.11588/heidok.00025681
%T The role of RLP44 in cell wall signalling integration and vascular cell fate determination in Arabidopsis thaliana
%U https://archiv.ub.uni-heidelberg.de/volltextserver/25681/
%X Plants are characterized by a highly plastic development governed by the interaction with the environment. The determination of plant cell fate depends of the integration on intrinsic and extrinsic stimuli, such as clonal cell identity and positional information obtained by non-cell autonomous signals. The aim of this work is to understand how plant cells integrate signals from the cell wall with intracellular growth-regulation processes and, as a consequence, how cell behaviour is influenced. We identified the receptor-like protein 44 (RLP44) of the model organism Arabidopsis thaliana as a putative sensor of cell wall pectate. RLP44 balances two crucial plant developmental signalling pathways: BRASSINOSTEROID (BR) signalling, a well-characterized pathway regulating plant growth, and the PHYTOSULFOKINE (PSK) signalling pathway. Genetic and biochemical analysis reveal a connection between the three receptors RLP44, BR INSENSITIVE 1 (BRI1), and PSK RECEPTOR 1 (PSKR1). Our data supports a model in which BRI1 controls vascular cell fate through transcriptional regulation of RLP44, independent of known BR signalling outputs. In addition, we describe a new role for RLP44, balancing two signalling pathways through direct interaction with the RLKs and modulation of their interaction with the respective co-receptor. We hypothesize that the PSK pathway is crucial for determination of procambial identity. Therefore, dynamic balancing of PSK and BR signalling may be a key regulatory step of vascular development in Arabidopsis thaliana.