Molecular cloning, expression pattern and prokaryotic expression of anti-Müllerian hormone (amh) gene in Osteoglossum bicirrostum

In order to explore the function and expression pattern of anti-Müllerian hormone (amh) gene in Osteoglossum bicirrostum, this study cloned the whole cDNA of amh gene in O. bicirrostum using RACE method, and found that O. bicirrostum had two different hypotypes——amh1 and amh 2(Genbank no.:KU378662, KU378663) of this gene. The result of sequence analysis showed that Amh1 had the full-length of 2277 bp, and encoded 623 amino acids; Amh2 had the full-length of 2181 bp, and encoded 355 amino acids. The homology analysis showed that the Amh in O. bicirrostum shared little conservation, and the similarity compared with its coordinal Scleropages formosus was the highest (85.64%), but that with fishes in other families was lower than 42%. Phylogenetic analysis showed that Amh came to be a cluster with Osteoglossiformes Amh and was closely related with lower teleost species such as Clupeiformes and Cypriniformes, which agreed with the evolutionary position of O. bicirrostum. The real-time fluorescent quantitative PCR results showed that amh was expressed generally in many tissues. The expression of amh1 was the highest in the testis, and much higher than that in ovary and other tissues. The expression of amh2 was also the highest in the testis, and much higher than that in other tissues, but much lower than the expression of amh1 in the testis. We constructed prokaryotic expression vectors pColdⅠ-amh1 and pColdⅠ-amh2, and successfully induced proteins of 68 and 48 ku in Escherichia coli, which laid the foundation for further study of amh in O. bicirrostum.