A receptor-like protein mediates the response to pectin modification by activating brassinosteroid signaling

Sebastian Wolf (1, 2) , Dieuwertje van Der Does (3) , Friederike Ladwig (4) , Carsten Sticht (5) , Andreas Kolbeck (2) , Ann-Kathrin Schurholz (2) , Sebastian Augustin (2) , Nana Keinath (2) , Thomas Rausch (2) , Steffen Greiner (2) , K. Schumacher , K. Harter , Cyril Zipfel (4) , Hermanus Höfte (1)

1 IJPB - Institut Jean-Pierre Bourgin
2 Ctr Organismal Studies
3 TSL - The Sainsbury Laboratory [Norwich]
4 Ctr Plant Mol Biol- Dept Plant Physiol
5 Zentrum Med Forsch

The brassinosteroid (BR) signaling module is a central regulator of plant morphogenesis, as indicated by the large number of BR-responsive cell wall-related genes and the severe growth defects of BR mutants. Despite a detailed knowledge of the signaling components, the logic of this auto-/paracrine signaling module in growth control remains poorly understood. Recently, extensive cross-talk with other signaling pathways has been shown, suggesting that the outputs of BR signaling, such as gene-expression changes, are subject to complex control mechanisms. We previously provided evidence for a role of BR signaling in a feedback loop controlling the integrity of the cell wall. Here, we identify the first dedicated component of this feedback loop: a receptor-like protein (RLP44), which is essential for the compensatory triggering of BR signaling upon inhibition of pectin de-methylesterification in the cell wall. RLP44 is required for normal growth and stress responses and connects with the BR signaling pathway, presumably through a direct interaction with the regulatory receptor-like kinase BAK1. These findings corroborate a role for BR in controlling the sensitivity of a feedback signaling module involved in maintaining the physico-chemical homeostasis of the cell wall during cell expansion.

Mots clés: brassinosteroids; cell wall integrity; pectin

Domaines: Sciences du Vivant [q-bio]

Sebastian Wolf, Dieuwertje van Der Does, Friederike Ladwig, Carsten Sticht, Andreas Kolbeck, et al.. A receptor-like protein mediates the response to pectin modification by activating brassinosteroid signaling. Proceedings of the National Academy of Sciences of the United States of America, 2014, 111 (42), pp.15261-15266. ⟨10.1073/pnas.1322979111⟩. ⟨hal-01204121⟩