Molecular cloning, characterization and expression analysis of the fatty acid-binding protein (MnFABP), involved in dietary lipid sources response in oriental river prawn, Macrobrachium nipponense

A fatty acid-binding protein (FABP) gene designated as MnFABP10 was cloned and characterized from the freshwater prawn Macrobrachium nipponense. The full-length cDNA of MnFABP10 was 646 bp encoding a 130 amino acid. Real-time quantitative RT-PCR showed that the MnFABP10 gene was expressed in various tissues with the highest expression in the hepatopancreas. The MnFABP10 mRNA levels in the hepatopancreas and ovary of M. nipponense were dependent on the stages of ovarian development. Western blot results revealed a single immunoreactive band with an estimated molecular mass of approximate 14 kDa in the developmental ovary. Then, M. nipponense with an initial body weight of 0.090 ± 0.0010 g were fed with four isonitrogenous and isocaloric diets with different oils, that is, beef tallow (BT), soybean oil (SO), pollack fish oil (FO) and a mixture of fish oil and soybean oil (FO/SO 2 : 1 w/w) for 52 days. The mRNA levels of MnFABP10 in the hepatopancreas were influenced by different lipid sources, with a peak expression observed in prawns fed SO. This study suggests that MnFABP10 may have a putative function in ovary maturation, and its mRNA expression in the hepatopancreas can be regulated by the source of dietary lipids in M. nipponense.