phylogenetic and sequence analysis of the growth hormone gene of two sturgeons, huso huso and acipenser gueldenstaedtii

in this study, the cdna growth hormone (cgh) of the belugasturgeon (husohuso) and russian sturgeon (acipensergueldenstaedtii) were cloned and sequenced, and phylogenetic relationships were examined using nucleic acid and amino acid sequences. the nucleotide sequence of the beluga gh has an open reading frame of 645 nucleotides encoding a protein 214 amino acid residues. the signal peptide cleavage site was predicted to be at position 72, yeilding a signal peptide of 24aminoacid residues and a mature peptide of 190 amino acids. the cdnasequence of the russian sturgeon was similar to that of the beluga cgh. the phylogenetic analysis was performed based on amino acid and dna sequences using the neighbor oining(nj) and maximum parsimony (mp) method. phylogenic trees by the two methods wereidentical in most of the clades with the high bootstrap support, and the topology of amino acid and dna sequences showed highest similarity with mammalian sequences.