MOLECULAR STRUCTURE AND EXPRESSION OF MYOSTATIN INMEGALOBRAMA AMBLYCEPHALA AND ITS OVEREXPRESSION EFFECTS IN EMBRYO

The current study cloned a 2187 bp full-length cDNA of myostatin from blunt snout bream (Megalobrama amblycephala) by rapid amplification of cDNA ends (RACE). Its open reading frame is 1128 bp encoding 376 amino acids. RT-PCR analysis demonstrated that MSTN are extensively expressed in tissues of blunt snout bream with high level in the muscle, brain and testis is the highest, modest level in the liver, spleen, and ovary, and low level in intestine, gills, heart, eye, and kidney. During embryos development, mRNA level of MSTN is low from 0 to 44 hpf, whereas its expression increases gradually from 48 hpf to 52 hpf. The whole mount in situ hybridization demonstrated that MSTN mRNA was transcribed at different tissues of blunt snout bream’s embryos. MSTN mRNA were detected at the Notochord at 16 hpf. In 28 hpf and 55 hpf embryos, the MSNT mRNA level was very high in brain. Overexpression MSTN mRNA in embryos caused elongated anterior-posterior axis, shorter dorsal-ventral axis, slightly distorted notochord, and strongly inhibited somites. This study provides knowledge for subsequent blunt snout bream MSTN gene function research and molecular breeding of blunt snout bream.