Disülfit bağı, CTNIP4 fitositokin katlantısını HSL3 reseptör kinazının tanıması için şekillendirir

Özet (abstract)

Abstract Precise ligand recognition by closely related leucine-rich repeat receptor kinases (LRR-RKs) is essential for plants to coordinate immunity, development and environmental adaptation. Here we show how the LRR-RK HSL3/NUT specifically recognizes the folded, disulfide-stabilized CTNIP4/SCREW2 phytocytokine in Arabidopsis . Quantitative binding assays define a minimal CTNIP4 region required for high-affinity HSL3 interaction and signalling activation. A 2.12-Å crystal structure of the HSL3–CTNIP4 complex reveals a unique C-terminal receptor pocket that accommodates the peptide’s cyclic architecture through a combination of hydrophobic and polar contacts, a feature absent in the closely related HAE/HSL LRR-RKs. The cyclic CTNIP4 fold further establishes a largely hydrophobic interface that bridges HSL3 to the SERK co-receptor, forming a distinct activation surface. Together, these structural, biochemical and physiological insights uncover a previously unrecognized mechanism of CTNIP4 peptide perception and HSL3 receptor activation, highlighting how subtle architectural variations enable precise ligand selectivity among highly conserved plant receptor kinases.

Yazarların özeti; kaynağından alınmıştır. Nature Plants, 2026 · DOI ↗