TSPO-induced degradation of the ethylene receptor RhETR3 promotes salt tolerance in rose ().

The gaseous plant hormone ethylene regulates plant development, growth, and responses to stress. In particular, ethylene affects tolerance to salinity; however, the underlying mechanisms of ethylene signaling and salt tolerance are not fully understood. Here, we demonstrate that salt stress induces the degradation of the ethylene receptor ETHYLENE RESPONSE 3 (RhETR3) in rose (). Furthermore, the TspO/MBR (Tryptophan-rich sensory protein/mitochondrial benzodiazepine receptor) domain-containing membrane protein RhTSPO interacted with RhETR3 to promote its degradation in response to salt stress. Salt tolerance is enhanced in -silenced rose plants but decreased in -silenced plants. The improved salt tolerance of -silenced rose plants is partly due to the increased expression of () and , which results in an increase in ethylene production, leading to the activation of () expression and, ultimately accelerating HO scavenging under salinity conditions. Additionally, overexpression of increased the salt sensitivity of rose plants. Co-overexpression with alleviated this sensitivity. Together, our findings suggest that RhETR3 degradation is a key intersection hub for the ethylene signalling-mediated regulation of salt stress.