Gonadal lipidomics profile of an ovoviviparity teleost, black rockfish, during gonadal development.

In order to study the variation of gonad lipidomics during reproductive cycle, black rockfish was employed as the research model in the present study. Using histology, lipidomics, and qPCR, the profile of gonad lipidomics and the expression levels of related genes during different developmental stages were detected and analyzed to show the potential regulatory network of lipid metabolism. Based on Ultra High-Performance Liquid Tandem Chromatography Quadrupole Time of Flight Mass Spectrometry (UHPLC-QTOFMS), four significant differential glycerophospholipid metabolic pathways including phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidic acid (PA) were enriched by KEGG. Pathway-related enzyme-coding genes, including phosphatidylserine decarboxylase (pisd), phosphatidylserine synthase (ptdss1, ptdss2), and phospholipase D (pld1, pld2) were identified from the whole genome data and confirmed by cloning. The expression profiles of these genes were tested by qPCR in the tissues and gonads in developmental stages, and we found that pisd, pld, and ptdss genes were all downregulated through the developmental process in the brain of male, and the latter two genes were upregulated in the liver and testis at stage IV, which were the opposite trend observed in the female. Thus, our findings would be helpful in further understanding the substance metabolism and regulation during gonad development in ovoviviparity teleosts.