Ethylene receptor related to bacterial two-component regulators. Acts as a redundant negative regulator of ethylene signaling. Binds 1 copper ion per dimer. Heteromer with ETR1 (PubMed:18577522). Binds to MRF3/ECIP1 (PubMed:21631530). Expressed in seedlings, roots, leaves, flowers, mature siliques, shoot apical meristems, leaf primordia, inflorescence meristems, young floral meristems, developing petals, carpels and ovules. Low expression in stamens. By ethylene. The GAF domain is sufficient to mediate heteromerization. Autophosphorylated predominantly on Ser residues. ETR2 is degraded by a proteasome-dependent pathway in response to ethylene binding. Belongs to the ethylene receptor family. The article by Li et al was retracted by the editors after publication. Concerns were raised regarding a number of figure panels, such as partial overlap between the panels and duplication of protein gel analysis.