Characterization and expression of the follistatin-related protein gene in golden pompano Trachinotus ovatus larvae

Abstract

The follistatin-related protein (FRSP) gene performs numerous functions through binding with cell regulatory proteins in transforming growth factor beta (TGF-β) superfamily such as activin and myostatin. The FRSP gene has been extensively studied in human and other vertebrate models such as chick and mouse to explore its role for disease control and organogenesis. However, very limited information exists on the FRSP gene and its expression during fish ontogeny. In this study, full-length cDNA sequence of the FSRP gene was characterized using next generation sequencing (Illumina HiSeq2000) and mRNA expression was evaluated using qPCR in golden pompano Trachinotus ovatus (Linnaeus 1758) larvae. The FRSP gene was composed of 1500 bp with an open reading frame of 936 bp, encoded 311 amino acids that have molecular weight of 34.55 kDa. The deduced amino acids of the FSRP gene contained a signal peptide, Kazal domain and EF-hand calcium-binding domain. The FSRP gene of T. ovatus has closest identity and similarity with Siniperca chuatsi and Larimichthys rocea. The mRNA expression of the FRSP gene gradually increased from 0 to 2 day post hatch (DPH), reached maximum at 3 DPH, and significantly decreased from 4 DPH to 18 DPH. The mRNA analysis in tissues revealed higher levels of FRSP gene expression in the liver head and eye but lower levels of expression in the kidney, muscles, and head-kidney. This study provides useful information to explore the functional mechanism of FRSP gene in fish ontogeny.