Phospho-regulation of the plant leucine-rich receptor kinase ERECTA in controlling organ growth and stomatal patterning
2Howard Hughes Medical Institute, University of Washington, USA
3Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Japan
4The Sainsbury Laboratory, University of East Anglia, UK
5Department of Genome Sciences, University of Washington, USA
6Department of Molecular Biosciences, University of Texas, USA
In plants, leucine-rich receptor-like kinases (LRR-RLK) are the largest class of cell-surface receptors and regulate signaling in development and immunity. ERECTA is a LRR-RLK involved in multiple developmental processes along with responses to biotic and abiotic stress. In A. thaliana, ERECTA and its homologues, ERL1 and ERL2, perceive secreted cysteine-rich peptides, termed EPIDERMAL PATTERNING FACTORS (EPFs)/EPF-LIKES (EPFLs), and transduce the signal across the plasma membrane. Several EPF/EPFL peptides have been identified as agonists or antagonists of ERECTA in different pathways, and are linked to specific phenotypic characteristics such as stomatal differentiation, growth, leaf serration and others.
The underlying molecular mechanism by which this receptor activates its downstream signaling is still elusive. Here we show that the C-terminal tail domain of ERECTA is highly specific and evolutionary conserved and has a negative regulatory function. Removal of this domain conferred hyperactivity of ERECTA in inflorescence growth as well as stomatal development. In vivo and in vitro phosphorylation analysis of ERECTA identified the C-terminal tail as a major phosphorylation domain, which is required to ensure proper activation of specific ERECTA signaling. These results demonstrate conserved and unique features as to the molecular mechanism of action and regulation of plant LRR-RLKs.
Powered by Eventact EMS