Research Article Acipenser persicus Growth Hormone Gene Sequencing and its Structures

Administering growth hormone increases growth rate of cultured fish. The aim of this study was isolation and synthesis of Persian sturgeon (GH) cDNA. The total RNA was extracted from pituitary gland of Persian sturgeon and cDNA was synthesized. The full-length cDNA sequence of Persian sturgeon contains a 645 nucleotide open reading frame, which encoding a 214 amino acid protein. The position of the signal peptide cleavage site was predicted to be at position 72. After cleaving of a signal peptide of 24 amino acid residues, a mature peptide of 190 aa formed. The blast observed that the Persian sturgeon pre GH have highest nucleotide sequence similarity with Acipenseridae family and mammals GH. Secondary structure and tertiary structure of Persian sturgeon growth hormone gene were prediction by online software. The secondary structure of the GH revealed the predomination of a- helix (> 55%), the domains of high conservation across the vertebrate GH protein. The predicted 3D structure of Persian sturgeon growth hormone attributes to the typical 4-a-helix bundle protein conformation, the characteristic 3-D confirmation of growth hormones