Potential mechanism of the PDE-cAMP-related network action on hepatopancreatic necrosis syndrome of Chinese mitten crab (Eriocheir sinensis)

Abstract Hepatopancreatic Necrosis Syndrome (HPNS) has substantial impacts on the Chinese mitten crab Eriocheir sinensis industry. Here, transcriptome studies were used to reveal the regulatory mechanisms of HPNS. A reference hepatopancreas transcriptome of E. sinensis was de novo assembled and a transcriptome comparison was made between healthy and HPNS crabs. The results showed that HPNS within the hepatopancreas were characterized by significant energy and metabolism reactions, including glycerolipid, riboflavin, sphingolipid, and tyrosine metabolism, as well as lysosome and pancreatic secretion, vitamin digestion and absorption, melanogenesis, biotin metabolism, and fat digestion and absorption. These indicate that HPNS crabs appeared to have significant energy consumption. The apoptotic pathway in HPNS was also activated. The results showed that hepatopancreas whitening and atrophy in HPNS crabs might be related to metabolism and cell death. Further, based on the results, we hypothesized that the PDE-cAMP-related network that dominates gene expression was abnormal in HPNS crabs. The subsequent qPCR and other verification verified the transcriptome results. Besides, relevant drug irritation in vivo indicates that PDE-induced symptoms in E. sinensis were similar to those of HPNS and were affected by specific inhibitors. Therefore, the occurrence of HPNS in E. sinensis may be related to the disfunction of the PDE-cAMP-related network. Our study revealed the regulatory mechanisms and corresponding molecular regulatory strategies of HPNS that may help to elucidate the characteristics of this disease.