FK506 activates the BMP signaling pathway to regulate ovarian development in Portunus trituberculatus.

Bone morphogenic proteins (BMPs) play important regulatory roles in the development of follicles in mammals. However, studies on the roles of BMPs in ovarian development in low-level aquatic animals, especially the swimming crab Portunus trituberculatus, are limited. In this study, a BMP Ⅰ-type receptor-specific activator (tacrolimus, FK506) was administered at different concentrations via in vivo injection, and the effects of FK506 on the regulation of the BMP signaling pathway during ovarian development in P. trituberculatus were examined. The tissue and cell morphology was observed, and a combined transcriptomics, proteomics and metabolomics analysis was carried out. Crabs administered FK506 exhibited elevated GSI alongside reduced HSI compared to control and blank groups. The main biological processes enriched by joint analysis included lipid metabolism, sugar metabolism, and amino acid metabolism. Fatty acid composition analysis revealed that the activator may activate the BMP signaling pathway to promote ovarian development and accelerate the transport of unsaturated fatty acids from the hepatopancreas to the ovaries. Amino acid metabolism and carbohydrate metabolism provide transporter proteins and energy for lipid metabolism. This study is highly important because it reveals the molecular mechanism by which the BMP signaling pathway regulates gonadal development in a crustacean.