SpNox regulates the homeostasis in the hemolymph and gut of mud crab (Scylla paramamosain) by generating ROS

Hemolymph and midgut are important tissues in the invertebrate's immune response, ROS generated by SpNox plays a vital role in regulating microbiota and maintaining homeostasis. In this study, the function of SpNox in regulating the hemolymph and midgut homeostasis in mud crab (Scylla paramamosain) was investigated. The results showed that SpNox regulated the microbiota harboring the hemolymph and midgut of mud crab through generating ROS. Furthermore, the ROS (principally O2−) derived from SpNox can modulate the composition of microbiota in the hemolymph (including Bacteroides, Aeromonas, Alteromonas, and Lysobacter) and in the midgut (including Arcobacter, Aliivibrio, Hypnocyclicus, Carboxylicivirga, and Candidatus_Bacilloplasma). Apart from SpNox, other ROS-related genes also participate in the regulation of hemolymph microbiota at certain times. Further studies to explain the detailed mechanisms that SpNox regulates the microbiota in aquatic animals are promising, which can provide good theoretical support for the healthy culture of aquatic animals.