Integrated transcriptomic and proteomic insights into low-salinity stress adaptation in Penaeus monodon

Salinity is a critical environmental factor affecting the growth of crustaceans. As an economically important aquaculture species, the farming of Penaeus monodon is currently facing challenges from salinity fluctuations caused by climate change. However, studies utilizing multi-omics approaches to elucidate its molecular adaptation mechanisms to low salinity remain limited. This study systematically investigated the molecular regulatory mechanisms of P. monodon under low salinity stress (3 ‰) at different time points (6 h, 24 h, 96 h) using transcriptomic and proteomic technologies. A total of 927 DEGs and 928 DEPs were identified compared to the control group. This study revealed a dynamic adaptive strategy. At 6 h, P. monodon exhibited disruptions in energy metabolism and immune suppression, alongside the activation of immediate compensatory pathways. As the stress continued to 24 h, P. monodon showed a broad enhancement of metabolic activity, indicating a systemic effort to mitigate stress damage. After 96 h of exposure, P. monodon demonstrated a sustained upregulation of energy metabolism and the activation of detoxification systems, facilitating stable adaptive regulation. Furthermore, transcriptome-proteome integration analysis uncovered coordinated gene-protein regulatory patterns. This study provides the first multi-omics atlas of P. monodon's response to low salinity, which delineates a time-resolved molecular adaptation strategy. Our findings not only offer novel insights into osmoregulation but also deliver valuable molecular targets for breeding stress-resistant strains, presenting scientific basis for sustainable aquaculture facing environmental challenges.