The study demonstrates that subfamily I ethylene receptors form the core ethylene‑sensing module and act epistatically over subfamily II receptors, uniquely possessing Ca2+‑permeable channel activity that drives ethylene‑induced cytosolic calcium influx. This reveals a mechanistic link whereby subfamily I receptors integrate hormone perception with calcium signaling in plants.

The study used quantitative proteomics and co‑fractionation mass spectrometry to uncover rapid ethylene‑induced changes in protein abundance and complex formation during early seedling development, revealing extensive protein multimerization events that correlate with hypocotyl growth modulation. Small‑scale validation confirmed several identified proteins impact hypocotyl development, highlighting novel components of ethylene‑mediated growth regulation.

The study identifies a conserved hydrophobic core within the coiled‑coil (CC) domain of helper NLRs (NRCs) that is essential for NRC4-mediated cell death and immunity. Structural and functional analyses show that this core regulates subcellular localization, oligomerization, and phospholipid association of NRC4, highlighting a novel mechanistic feature of NLR function.