The involvement of reactive oxygen species in wounding-induced archeospores production in Neopyropia yezoensis

The archeospores released from the blades of Neopyropia yezoensis via dedifferentiated vegetative cells have drawn attention both in cultivation and research. Wounding-induced archeospores formation and release have been observed in N. yezoensis, but the mechanism behind them is unclear. In this study, the involvement of reactive oxygen species (ROS) in the process of wounding-induced archeospores formation and release was investigated. Based on ROS fluorescence observations, the blade fragments began to accumulate ROS after 12 h wounding, while no ROS signals were observed in normal blades. Next, when the blade fragments were treated with ROS inhibitor diphenyleneiodonium (DPI), it showed that the production of archeopores was significantly suppressed. Under normal culturing after wounding, 78.3% of the fragments could release archeospores, and the ROS fluorescence was enriched in the released archeospores. Under 0.05 μM DPI treatment, the percentage of fragments releasing archeospores was dropped to 16.2%, with decreased ROS fluorescence levels. Under 0.1 μM DPI treatment, no archeospores were released from the fragments, and ROS fluorescence was also undetectable in the fragments. Our findings proved that ROS are essential for wounding-induced archeospores production, which might play regulatory roles in the cell dedifferentiation of N. yezoensis.