2022 Volume 34 Issue 1 Pages 29-36
Plants have generated divergent peptide ligands and corresponding membrane receptors to control their growth and development, as well as various aspects of physiology. Secreted-peptide ligands are mainly recognized by membrane receptor kinases that mediate cell-cell communication. In Arabidopsis, more than 1,000 genes are putative secreted peptides and ~600 genes are annotated as receptor-like kinases. However, several pairs of the peptide ligands and the cognate receptors are identified and mechanistically characterized, many of them remain orphan ligands and receptors. In the past 5 years, structural and biochemical studies have revealed how the short liner peptides with post-translational modification are perceived by the corresponding receptors with leucine-rich repeats (LRR) ectodomain at a molecular level. The short linear peptides are recognized by the LRR-type receptors and co-receptors in a conserved manner. Moreover, the recent structural study has implied a new mode of peptide recognition by LRR receptors. This short review summarizes recognition mode of the secreted peptides by the LRR-type receptors and receptor-activation mechanisms that have been structurally characterized in recent studies.
