Integrative approaches for the structure-based functional understanding of the ethylene response in plants

Ethylene is a key plant hormone regulating growth, development, and stress responses, yet the structural basis of its perception and signaling remains only partially understood. Ethylene receptors, which reside in the endomembrane network, act as dynamic signaling hubs that integrate hormone binding, copper (Cu⁺) cofactor coordination, and protein-protein interactions to control downstream pathways. Despite progress in characterizing individual domains, the full-length structural organization of receptors and the mechanisms linking copper (Cu⁺) coordination to conformational signaling remain unclear. Equally, the functional significance of receptor multimerization and higher order clustering in shaping signaling robustness and cross-talk is only beginning to emerge. To address these gaps, integrative approaches that combine structural biology, advanced spectroscopic techniques, targeted mutagenesis, molecular dynamics simulations, and molecular bioinformatics are employed. Recent advances in cryo-electron microscopy (cryo-EM), cross-linking mass spectrometry, and super-resolution imaging offer unprecedented opportunities to capture conformational states, map transient receptor interfaces, and visualize clustering dynamics in living cells. Complementary structure prediction tools together with hybrid quantum/classical simulations and perturbation analyses further connect local binding events to long-range allosteric communication. This review focuses on these multidisciplinary strategies that pave the way toward a unified mechanistic framework of ethylene signaling.