Circadian Redox Rhythm in Plant–Fungal Pathogen Interactions
Meiling Liang, Lihong Dong, Yizhen Deng
Abstract
Significance: Circadian-controlled cellular growth, differentiation, and metabolism are mainly achieved by a classical transcriptional–translational feedback loop (TTFL), as revealed by investigations in animals, plants, and fungi. Recent Advances: Recently, reactive oxygen species (ROS) have been reported as part of a cellular network synchronizing nontranscriptional oscillators with established TTFL components, adding complexity to regulatory mechanisms of circadian rhythm. Both circadian rhythm and ROS homeostasis have a great impact on plant immunity as well as fungal pathogenicity, therefore interconnections of these two factors are implicit in plant–fungus interactions. Critical Issues: In this review, we aim to summarize the recent advances in circadian-controlled ROS homeostasis, or ROS-modulated circadian clock, in plant–fungus pathosystems, particularly using the rice ( Oryza sativa ) blast fungus ( Magnaporthe oryzae ) pathosystem as an example. Understanding of such bidirectional interaction between the circadian timekeeping machinery and ROS homeostasis/signaling would provide a theoretical basis for developing disease control strategies for important plants/crops. Future Directions: Questions remain unanswered about the detailed mechanisms underlying circadian regulation of redox homeostasis in M. oryzae , and the consequent fungal differentiation and death in a time-of-day manner. We believe that the rice– M. oryzae pathobiosystem would provide an excellent platform for investigating such issues in circadian-ROS interconnections in a plant–fungus interaction context. Antioxid. Redox Signal . 37, 726–738.