The t‐SNARE domain‐containing soybean cyst nematode HgSNARE1 is an effector that interacts with the GmSNAP18–GmSHMT08–GmPR1‐15 module and shows avirulence to soybean

Abstract BACKGROUND Soybean cyst nematode (SCN, Heterodera glycines ) poses a significant threat to soybean ( Glycine max (L.)), causing huge yield losses annually in global soybean production. Although the two main soybean SCN‐resistant genes, rhg1 GmSNAP18 and Rhg4 GmSHMT08 , have been cloned, the SCN effectors have been identified and functioned rarely, and the molecular mechanisms of effectors interacting with soybean remain largely unknown. Here, we identified the SCN effector HgSNARE1 and investigated how it targeted the soybean GmSNAP18–GmSHMT08–GmPR1‐15 module, aiming to reveal a new molecular mechanism for SCN control. RESULTS In this study, the t‐SNARE domain‐containing protein HgSNARE1 was identified as an effector from SCN that was expressed the highest at the third juvenile (J3) stage. Expression of HgSNARE1 in soybean hairy roots promoted SCN resistance, indicating the avirulence function of HgSNARE1 to soybean. HgSNARE1 interacted with GmSNAP18 via the t‐SNARE domain, with the last five amino acid residues (S 308 V 309 H 310 K 311 A 312 ) in the C terminus playing an essential role in the interaction. GmSNAP18 interacted with both GmSHMT08 and a pathogenesis‐related (PR) 1 protein GmPR1‐15 (Glyma.15 g062400), and GmSHMT08 interacted with GmPR1‐15. Therefore, GmSNAP18, GmSHMT08 and GmPR1‐15 formed a module by pairwise interactions. However, neither GmSHMT08 nor GmPR1‐15 interacted with HgSNARE1. Furthermore, expression of HgSNARE1 in soybean hairy roots stimulated expression of GmPR1‐15 . CONCLUSION These findings reveal a novel molecular mechanism by which the SCN effector HgSNARE1 interacts with SCN‐resistant GmSNAP18 of the GmSNAP18–GmSHMT08–GmPR1‐15 module and promotes GmPR1‐15 expression to confer avirulence, providing a potential target for the development of new SCN‐resistant germplasms, and innovative nematode management strategies. © 2025 Society of Chemical Industry.