Figure Legend
Fig. 1 Effects of Thioredoxins (TRXs) on Plant-Virus Interactions : Thioredoxins (TRXs), a small family of thiol-disulfide oxidoreductases, play a crucial role in the antioxidant defense system of plants by reducing ROS and maintaining cellular redox balance. Viruses target TRXs to interfere with their function, creating a microenvironment conducive to virus accumulation and intercellular movement. The outcome of the TRX-virus interaction varies based on the organelle associated with TRX: 1- Endoplasmic Reticulum (ER): TRX reductive activity on NPR1 oligomers occurs, leading to NPR-1 monomerization. Monomeric NPR-1 proteins translocate to the nucleus, acting as co-transcription factors for salicylic acid-related genes, such as the CALLOSE SYNTHASES (CALS ). Therefore, cytosolic TRXs regulate cell-to-cell movement in a salicylic acid (SA)-dependent manner, suggesting a potential role in controlling plasmodesmata permeability. 2- Chloroplast: TRX effects on ROS vary depending on the host and the virus. In N. benthamiana , NTRC induces ROS, promoting resistance to BSMV. BSMV interferes with NTRC, modifying the ROS environment to favor virus replication and spread. In Wheat, however, TaAAED1 induces susceptibility to WYMV by reducing ROS levels. 3- Plasma Membrane: ROS production at the plasma membrane viaRBOHD is involved in PVYN resistance in potatoes. SilencingRBOHD increases susceptibility and PVYNmovement despite high SA levels in RBOHD -silenced plants, indicating an uncoupled effect of RBOHD (and ROS) from SA in the PVY-potato pathosystem. 4- Mitochondria: Inhibition of alternative oxidase by salicylhydroxamic acid (SHAM) in tomato plants elevates mitochondrial ROS levels, facilitating fast trafficking of TMV.