N-glycosylation code diversifies paralogous chitinases to balance plant immunity and growth.

N-glycosylation determines functional divergence of paralogous plant chitinases, balancing immunity and growth in Arabidopsis thaliana.

• Why it matters: Understanding how plants manage the trade-off between immune responses and growth is crucial for improving crop resilience without yield loss. The mechanisms behind this balance, especially at the molecular level, remain poorly understood.
• What they did: The study identified two chitinases, MIC1 and MIC2, in Arabidopsis that differ in activity due to N-glycosylation at Asn137; removing this glycan switches MIC1 to a MIC2-like enzyme, with widespread presence of MIC1-like chitinases in plants and enhanced fungal resistance observed in Oryza sativa Osmic1 mutants.
• The result: This N-glycosylation code enables functional specialization of chitinases, offering a conserved target for breeding crops with improved fungal resistance while maintaining normal growth.