Abstract:Myostatin (Mstn) is one of the main regulatory factors of embryonic muscle formation and adult muscle growth in vertebrates, which inhibits muscle growth and development by inhibiting the expansion and differentiation of muscle cells. Our previous researches have preliminarily suggested that Mstn involved in myogenesis and muscle growth probably as a negative regulator in Fenneropenaeus chinensis like vertebrates. In order to screen genes related to muscle growth regulated by Mstn in F. chinensis and understand the mechanism of muscle growth regulation, RNA-Seq technology was used to sequence control group injected PBS and experimental group injected siRNA for inhibition of Mstn expression. The results showed that a total of 36,605 unigenes were produced and 19,628 genes were annotated by transcriptome analysis. Under the inhibition of Mstn expression by RNAi, a total of 1657 differentially expressed genes were screened, of which 805 genes were significantly up regulated and 852 genes were significantly down regulated. Referring to the previous reports of TGF-β/Smad and MAPK pathways as well as function of differential genes, 29 genes related to muscle growth regulated by Mstn were preliminarily screened. In these genes, 16 genes were involved in TGF-β/Smad and Mapk pathways. Among the 16 genes, only the ActRI was detected to be slightly up-regulated and other genes showed different degrees of down-regulation. The other screened 13 genes were involved in molting, muscle growth and other processes related muscle such as muscle contractions, of which the genes correlated with promoting muscle growth were detected up-regulation. The results of this study provided further evidence for our previous studies that Mstn probably negatively regulates muscle growth in a similar way to vertebrate in F. chinensis. Our results will also provide important theoretical basis for the regulation mechanism of muscle development in invertebrate.
