藏绵羊生长激素(GH)基因的克隆及序列分析

【Objective】 The Tibetan sheep growth hormone (GH) gene was cloned and sequenced, comparisons of the sequence and the deduced amino acid sequence with the homologous GH gene and protein sequence of the GHs in other species including other sheep, goats, cattles, zebu, frontalis, yaks and buffalo retrieved from the GenBank were performed in order to provide theoretical foundation for further research of the corelevantion of Tibetan sheep GH gene and growth traits, location and expression i.e.【Method】 The Tibetan sheep GH gene was amplified using particular primers, cloned by T-A method and sequenced, based on this the nucleotide and amino acid sequences among different species were compared and analyzed by DNAMAN 4.0、 Bdit 7. 0. 0、 DnaSP 4.10.1 softs. 【Result】 The numbers of exons and introns of Tibetan sheep GH gene (GenBank Accession NoEF077162) were the same with those in other sheep, goats, cattles, zebu, frontalis, yaks and buffalo, they had 5 exons and 4 introna The size of CBS sequenc of the Tibetan sheep GH gene, encoding 217 amino acids (including signal peptide composed of 26 amino acids and Mature peptide composed of 191 amino acids), was 654 bp. The size of exon Ⅰ, exon Ⅱ, exon Ⅲ, exon Ⅳ and exon Ⅴ was 13, 161, 117, 162 and 201 bp respectively; while the size of intron Ⅰ, intron Ⅱ, intron Ⅲ and intron Ⅳ was 246, 227, 229 and 27 bp respectively. The junction sequence of introns and exons of Tibetan sheep GH gene was in accordance with the law of gene composition. The homology rates of nucleotide sequences of the coding region of GH gene and deduced amino acid sequences of GHs among Tibetan sheep and other sheep were 99%-100%. The homology rates of nucleotide sequences of the coding region of GH gene among Tibetan sheep and goats, cattles, zebu, frontalis, yaks and buffalo were 98.4%, 98.04, 97.7%, 97.54, 97.5%, 98.1% respectively, while the homology rates of deduced amino acid sequences of GHs were 100%, 99.0%, 99.0%, 98.1%, 98.6%, 98.1% respectively. [Conclusion] The Tibetan sheep Gil gene was successfully cloned in this study. The nucleotide sequences of the coding region of the GH gene and dedued amino acid sequences among species in Bovidae were quite conservative.