Transcriptomic analyses of the low-pH stress response in the hepatopancrea of the Marsupenaeus japonicus
Ocean acidification poses a growing threat to marine aquaculture, yet the molecular mechanisms underlying crustacean responses to acid stress remain unclear. In this study, we employed RNA-Seq to investigate the hepatopancreatic transcriptomic responses of M. japonicus under low-pH stress (pH 5.0) across six time points (3-96 h). A total of 2705 DEGs were identified. KEGG enrichment analyses revealed significant involvement of DEGs in immune regulation, oxidative stress response, apoptosis, and energy metabolism. Key pathways such as lysosome, Toll-like receptor, AMPK, and PPAR signaling were dynamically regulated. During early exposure, most immune- and antioxidant-related genes were downregulated, suggesting acute physiological suppression. However, compensatory upregulation was observed at 96 h, indicating an adaptive response. Protein interaction analysis identified nine hub genes, including NADH-GOGAT and MDHM, which may play key roles in antioxidant defense and metabolic regulation. RT-qPCR validation of 19 selected DEGs confirmed the reliability of the transcriptomic data. Overall, our findings provide novel insights into the molecular adaptation mechanisms of M. japonicus to acidified environments and offer a valuable resource for developing acid-tolerant shrimp strains, contributing to the sustainability of aquaculture under future ocean acidification scenarios.