Structural basis for recognition of an endogenous peptide by the plant receptor kinase PEPR1

• Published in: Cell research Vol. 25; no. 1; pp. 110 - 120
• Main Authors: Tang, Jiao, Han, Zhifu, Sun, Yadong, Zhang, Heqiao, Gong, Xinqi, Chai, Jijie
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-01-2015; Nature Publishing Group
• Subjects: 631/449/1659; 631/45/535; Amino Acid Sequence; Amino acids; Arabidopsis - chemistry; Arabidopsis - metabolism; Arabidopsis Proteins - chemistry; Arabidopsis Proteins - metabolism; Biomedical and Life Sciences; Cell Biology; Crystallography, X-Ray; Life Sciences; Models, Molecular; Molecular Sequence Data; Original; original-article; Peptides; Peptides - chemistry; Peptides - metabolism; Protein Structure, Tertiary; Receptors, Cell Surface - chemistry; Receptors, Cell Surface - metabolism; Sequence Alignment; 免疫应答; 内源性; 受体激酶; 晶体结构; 植物; 结构基础; 肽; 识别; AtPeps; crystal structure; repeat-receptor kinase; BAK1; PEPR1; LRR
• ISSN: 1001-0602; 1748-7838
• DOI: 10.1038/cr.2014.161

The endogenous peptides AtPepl-8 in Arabidopsis mature from the conserved C-terminal portions of their precursor proteins PROPEP1-8, respectively. The two homologous leucine-rich repeat-receptor kinases （LRR-RKs） PEPR1 and PEPR2 act as receptors of AtPeps. AtPep binding leads to stable association of PEPR1,2 with the shared receptor LRR-RK BAK1, eliciting immune responses similar to those induced by pathogens. Here we report a crystal structure of the extraceUular LRR domain of PEPRI （PEPR1LRR） in complex with AtPepl. The structure reveals that AtPepl adopts a fully extended conformation and binds to the inner surface of the superhelical PEPRILRR. Biochemical assays showed that AtPepl is capable of inducing PEPR1LRR-BAK1LRR heterodimerization. The conserved C-terminal portion of AtPepl dominates AtPepl binding to PEPRILRR, with the last amino acid of AtPepl Asn23 forming extensive interactions with PEPR1LRR. Deletion of the last residue of AtPepl significantly compromised AtPep1 interaction with PEPRILRR. Together, our data reveal a conserved structural mechanism of AtPep1 recognition by PEPR1, providing significant insight into prediction of recognition of other peptides by their cognate LRR-RKs.