Figure 1.

Hypothetical model for the potential function of NO, H₂O₂ and ethylene as signaling molecules in AP induction under salt stress in Arabidopsis. Salt stress activates a signal transduction cascade that leads to the increased activity of AOX, whose expression leads to enhanced AP activity. NO is generated by NOS, H₂O₂ is likely generated by PM NADPH oxidase attributed to NO, and ethylene emission is stimulated by ACS attributed to H₂O₂. The AP activity is regulated by ethylene directly under salt stress.