Résumé
Growth Hormone (GH) is a single polypeptide chain synthesised and secreted from anterior pituitary gland by somatroph cells. The product of GH gene hastens metabolism and promotes the growth of many organs and tissues especially bone, muscle and visceral organs. It also regulates growth, mammary gland development and lactation. Polymorphism in this gene is associated with increase in growth and development of many tissues in the body. Aim: The objective of this study was to investigate the polymorphism of bovine growth hormone (bGH) gene in buffalo bulls (Bubalus bubalis) using the PCR-RFLP (polymerase chain reaction–restriction fragment length polymorphism) technique. Design: Genomic DNA was extracted from a total of 10 bulls, consisting of Murrah – Swamp crossbred and pure Swamp buffalo bulls. A The 446 segment of the bGH gene was amplified. The DNA amplicons were detected in 2% agarose gel following 45 minutes of electrophoresis. They were thereafter digesting with AluI endonuclease restriction enzyme, and the digested DNA were detected in 2% agarose gel following electrophoresis for about 45minutes in all samples Results: Similar bands of approximately 300 and 146-bp each, with no variation, were detected in 2% agarose gel following electrophoresis in all the animals tested. Conclusion: Based on the Alu1 digestion result, all samples produced the same allele of the gene, with no polymorphism detected.
Résumé
Bovine growth hormone (bGH) gene was expressed in an insect spodoptera frugiperda cell line using a Baculovirus, Hyphantria cunea nuclear polyhedrosis virus (HcNPV). The bGH gene in pbGH plasmid was sequenced and amplified by PCR technique with two primers containing NcoI sites. The bGH gene consisted of 654 bp (217 amino acid residues), the 5'-untranslated region of the cloned bGH cDNA contains 56 bp, and the 3'-untranslated region contains 145 bp and two pallindromic regions. The amplified bGH gene DNA fragment (654 bp) was inserted into the NcoI site of the pHcEVII vector, which was named pHcbGH. The pHcbGH transfer vector DNA and the wild type HcNPV DNA were cotransfected into s. frugiperda cells to construct a recombinant virus. Eight recombinant viruses were selected and named HcbGH. One clone, HcbGH-4-1 showed largest plaque size, therefore the recombinant virus was further studied. The multiplication patters of the recombinant HcbGH-4-1 was similar to that of the wild type HcNPV. The bGH gene DNA in the HcbGH-4-1 recombinant was confirmed by Southern lot hybridization. The amount of the bGH (217 amino acid residues, 21 kDa) produced in S. frugiperda cells infected with the HcbGH-4-1 recombinant was approximately 5.5 ng per ml (106 cells) by radioimmunoassay.