Reversible S-acylation of BONZAI1 orchestrates the internalization of immune receptors to balance plant development and immunity.

Plants have developed a precise immunity system for disease resistance and the receptors on the plasma membrane is controlled by endocytosis to modulate immune signaling, but endocytosis regulation in this process is unclear. Here we uncover that reversible S-acylation of BONZAI1 (BON1), a conserved copine family protein for development-immunity balance in Arabidopsis, contributes to accurate control of endocytosis. BON1 is targeted by S-acylation, a type of protein lipidation, for its localization on the plasma membrane and its function in development and immunity. Furthermore, the S-acylation status of BON1 affects its association with a light-chain clathrin subunit CLC3 and regulates endocytosis. Specifically, PAT14 facilitates the S-acylation of BON1, while ABAPT11 mediates its de-S-acylation. A physiological level of this reversible S-acylation of BON1 is essential for endocytosis and the internalization of immune receptors. Interestingly, salicylic acid enhances the ABAPT11-dependent de-S-acylation of BON1 for amplifying immunity signaling. This work on endocytosis regulation in plant development-immunity balance would assist with the improvement of crop yields and disease resistance.