Abstract:To explore the regulation of lysophosphatidylglycerol acyltransferase (LPGAT) expression patterns during the ovarian development of Eriocheir sinensis, the open reading frame (ORF) sequence of Es-lpgat1 of E. sinensis (accession number: MZ312613) was cloned. Then, its temporal and spatial expression patterns during ovarian development were analyzed using real-time quantitative polymerase chain reaction (qRT-PCR), in situ hybridization, and RNA interference. The results showed that the ORF of Es-lpgat1 was 1125 bp in length, en-coding a 374-amino acid protein with a molecular weight of 44 kD. It belonged to the LPGAT superfamily, and the amino acid sequence deduced from Es-lpgat1 exhibited the highest identity with Portunus trituberculatus. qRT-PCR results showed that Es-lpgat1 was expressed in different tissues during the ovarian development of E. sinensis, with the highest expression in the ovary and the lowest level in the gills (P<0.05). During the ovarian development cycle, both the hepatopancreas and ovary at ovarian stage II presented the highest expression levels of Es-lpgat1mRNA (P<0.05), and there was a significant increasing trend during the period from ovarian stage III to stage V. The results of in situ hybridization showed that in ovarian stage II, the strong signal of Es-lpgat1 mRNA was localized in the cytoplasm of previtellogenic oocytes and endogenous vitellogenic oocytes of the ovary, while a very weak signal was detected in stage IV ovaries. However, a strong signal of Es-lpgat1 mRNA was localized in fibrillar cells (F cells) and resorptive cells (R cells) of hepatopancreas at stages II and IV. After knockdown of Es-lpgat1, the expression levels of Es-gpat2 and Es-dgat2 were significantly up-regulated, while the expression levels of Es-agpat4 and Es-dgat1 were significantly down-regulated. In summary, Es-lpgat1 mRNA was mainly expressed in the ovary and hepatopancreas of E. sinensis, which was significantly related to the ovarian stages. These results suggested that Es-lpgat1 may be involved in phospholipid metabolism during ovarian development of E. sinensis.