Characterization of a Myostatin-like Gene from the Scallop Patinopecten yessoensis

Abstract

Myostatin (GDF8) is a growth factor that limits muscle tissue growth and development in vertebrates. We isolated a myostatin-like gene (Py-MSTN) from the marine invertebrate the scallop Patinopecten yessoensis. Py-MSTN was highly expressed in the adductor muscle and in the gill unexpectedly. Amino acid analysis showed that Py-MSTN has 49% amino acid sequence identity and 64% similarity to human myostatin (Hs-MSTN), and 42% identity and 61% similarity to myoglianin, the only invertebrate homolog. These results indicated that Py-MSTN may be functionally similar to the vertebrate MSTN than the invertebrate homolog. Phylogenetic analysis suggested that Py-MSTN is an ancestral form of vertebrate MSTN and GDF11 and does not belong to other TGF-ß family members. Molecular modeling showed that Py-MSTN exhibits a similar tertiary structure to mammalian BMP7, a member of TGF-ß family. In addition, the amino acid residues which contact extracellular domain of the receptor were relatively conserved. Given these results, we propose that Py-MSTN is a functionally active member of the TGF-ß family and that it is involved in muscle growth and regulation.