CLONING AND EXPRESSION OF A HUMAN INTERFERON a2 GENE IN E. COLI

Abstract

The plasmid pALCA1SIFN containing cDNA that encodes the human interferon a-2b was obtained from the ATCC(no. 531667). In this system the expression of the gene is under the control of an alcA promoter. alcA p is a specific promoter for expression of different genes in Aspergillusfilamentous. In this plasmid the coding region of IFN?-2b is preceded by the coding region of a synthetic signal peptide. For direct expression of the IFNa-2b gene under the control of a T7/lac promotor of pET24d(+) expression vector, three subcloning steps were carried out which resulted in the construction of 3 new plamids. pHA1, pHA2 and pHA4 in which the IFNa-2 gene is under the control of lacp, lacuv5p and T7 promoter, respectively. Another plasrnid, pHA3, was also constiucted and is a modified version of pET24d(+). Provided there is a synthetic signal peptide preceding the coding region of IFNa2 gene, the protein can be seen in either system, as shown by western blotting, albeit with a different level of expression. The best product can be seen in the pHA4plasmid with a T7 pas judged by dot and western blotting