Endomembrane Ca²⁺-ATPases play a significant role in virus-induced adaptation to oxidative stress

Although the role of Ca²⁺ influx channels in oxidative stress signaling and cross-tolerance in plants is well established, little is known about the role of active Ca²⁺ efflux systems in this process. In our recent paper, we reported Potato Virus X (PVX)- induced acquired resistance to oxidative stress in Nicotiana benthamiana and showed the critical role of plasma membrane Ca²⁺/H⁺ exchangers in this process. The current study continues this research. Using biochemical and electrophysiological approaches, we reveal that both endomembrane P_2A and P_2B Ca²⁺-ATPases play significant roles in adaptive responses to oxidative stress by removing excessive Ca²⁺ from the cytosol, and that their functional expression is significantly altered in PVX-inoculated plants. These findings highlight the crucial role of Ca²⁺ efflux systems in acquired tolerance to oxidative stress and open up prospects for practical applications in agriculture, after in-depth comprehension of the fundamental mechanisms involved in common responses to environmental factors at the genomic, cellular and organismal levels.