Acetylation enables a dual-targeting fungal effector to inhibit insect immunity and development.

Acetylation of the fungal effector MrNIS1 enhances its stability and enables dual targeting of insect immune and developmental pathways, boosting pathogen efficacy.

• Why it matters: Understanding how effectors maintain functionality across different hosts is crucial for developing effective biocontrol strategies and combating insect pests.
• What they did: The study identified MrNIS1 from Metarhizium robertsii, showing its stability depends on K24 acetylation mediated by MrKAT1 and MrSIR2, and demonstrated its dual targeting of immune and developmental pathways in insects.
• The result: Acetylation acts as a molecular switch preserving effector activity during host transition, revealing conserved fungal strategies and offering targets to enhance microbial biocontrol agents' effectiveness.