Salt Natural cis Salt stress stress tolerance antisense RNA SRos 1- RoSt+psct- SCD roin Degradation of p5cdh mrNA decreases P5CDH activity and proline degradation. Decreased proline degradation contributes to salt-induced P5CDH proline accumulation and salt tolerance Constitutive induced but at the same time leads to the ros P5CDH mRNAK Accumulation caused by buildup of the SRO5 mi P5CDH proline catabolic intermediate P5C. This mRNA ROS accumulation is potentially harmful but is also a signal to initiate further DCL2 24-nt nat-siRNA 曹 formation and stress responses. The Sro5 protein initial cleavage SGS3 RISC counteracts P5C-induced ROS SDE4 accumulation, thus completing a dsRNA and regulatory loop that allows fine tuning of 21-nt nat-siRNA DCL1 formation ROS accumulation and stress responseNatural cis￾antisense RNA Degradation of P5CDH mRNA decreases P5CDH activity and proline degradation. Decreased proline degradation contributes to salt-induced proline accumulation and salt tolerance but, at the same time, leads to the ROS Accumulation caused by buildup of the proline catabolic intermediate P5C. This ROS accumulation is potentially harmful but is also a signal to initiate further stress responses. The SRO5 protein counteracts P5C-induced ROS accumulation, thus completing a regulatory loop that allows fine tuning of ROS accumulation and stress response