Expression of HSV-1 ICP0 antigen peptide in prokaryotic cells and preparation of specific antibody

Abstract

As an immediate-early protein of herpes simplex virus, infected-cell polypeptide 0 (ICP0) exhibits complicated interactions with host cells, and its regulatory function on gene expression is of great importance. Since the ICP0 encoding sequence contains many rare codons which are absent in E.coli, and ICP0 is highly unstable in prokaryotic cells, expression of entire ICP0 in prokaryotic cells has never been reported. In order to further investigate the function of ICP0, a recombinant plasmid was constructed by subcloning a cDNA fragment encoding an amino-terminal of 105 residues of the ICP0 protein into pGEX-5x-1 vector. The resulting GST-105 fusion antigen peptide was expressed with high efficiency in E.coli. Antibodies prepared after the immunization of mice with purified fusion protein can recognize not only the denatured ICP0 protein, but also the native ICP0 protein with normal biological conformation.