N-glycosylation facilitates the activation of a plant cell-surface receptor

ABSTRACT: Plant receptor kinases (RKs) are critical for transmembrane signaling involved in various biological processes including plant immunity. MALE DISCOVERER1-INTERACTING RECEPTOR-LIKE KINASE 2 (MIK2) is a unique RK that recognizes a family of immunomodulatory peptides called SERINE-RICH ENDOGENOUS PEPTIDEs (SCOOPs) and activates pattern-triggered immunity (PTI) responses. However, the precise mechanisms underlying SCOOP recognition and activation of MIK2 remain poorly understood. In this study, we present the cryo-EM structure of a ternary complex consisting of the extracellular leucine-rich repeat of MIK2 (MIK2LRR), SCOOP12, and the extracellular LRR of the co-receptor BAK1 (BAK1LRR) at a resolution of 3.34 Å. The structure reveals that a DNHH motif in MIK2LRR plays a critical role in specifically recognizing the highly conserved SxS motif of SCOOP12. Furthermore, the structure demonstrates that N-glycans at MIK2LRRAsn410 directly interact with the N-terminal capping region of BAK1LRR. Mutation of the glycosylation site, MIK2LRRN410D, completely abolishes the SCOOP12-independent interaction between MIK2LRR and BAK1LRR and significantly impairs the assembly of the MIK2LRR-SCOOP12-BAK1LRR complex. Supporting the biological relevance of N410-glycosylation, MIK2N410D substantially compromises SCOOP12-triggered immune responses in plants. Collectively, these findings elucidate the mechanism underlying the loose specificity of SCOOP recognition by MIK2 and reveal an unprecedented mechanism by which N-glycosylation modification of LRR-RK promotes receptor activation.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Trichoplusia Ni

TISSUE(S): Cell Suspension Culture

SUBMITTER: Fangshuai Jia  

LAB HEAD: Jijie Chai

PROVIDER: PXD054177 | Pride | 2024-10-22

REPOSITORIES: Pride