Integrated Multi-omics Analysis Reveals that Hybrid Rice Reprograms Carbon Metabolism to Confer Drought Resistance

Importantly, NAE-driving AcCoA accumulation correlates with elevated lysine acetylation (Kac) in HY73, establishing a bridge between metabolic flux and post-translational regulation. Acetylomic analyses pinpointed acetylation at lysine 155 (K155ac) on OsPGM3, a previously uncharacterized cytosolic phosphoglucomutase, as a pivotal regulatory switch. CRISPR/Cas9-mediated gene editing and biochemical assays demonstrated that drought-induced deacetylation activates OsPGM3, ensuring sufficient glucose-6-phosphate (G6P) for the lipid shunt while maintaining stable glucose-1-phosphate (G1P)-mediated sucrose export vital for yield potential.

Thus, K155ac precisely fine-tunes OsPGM3 activity, acting as a post-translational checkpoint responsive to drought-induced carbon shifts. Together, our findings establish a hybrid-specific NAE–carbon flux–Kac regulatory axis that precisely balances drought adaptation with yield maintenance, offering new targets for breeding climate-resilient hybrid rice.