Abstract: Objective To express and purify the recombinant protein, and to prepare the c18orf54 specific rabbit polyclonal antibody.
Methods c18orf54 cDNA was ligated into the prokaryotic expressive vector pET-32a(+), and the resulting plasmid was transformed into E.coil BL21(DE3). The protein expression was induced with IPTG and the protein was analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and Western blotting. The expressed product was purified using Ni⁺ affinity column chromatography. The recombinant protein was also confirmed with mass spectrometry. Then the purified C18ORF54 fusion protein was used to immunize New Zealand rabbits to gain polyclonal antibody. The specificity and potency of polyclonal antibody were evaluated by Western blotting and ELISA.
Results The C18ORF54 fusion protein was highly expressed. The protein was mainly in the inclusion body. ELISA indicated the titer of polyclonal antibody>1∶320 000. The high specificity was confirmed with Western blotting. Immunohistochemical staining of liver tissue showed that this glycosyltransferase was mainly scattered in cytoplasm of hepatocytes.
Conclusion The recombinant C18ORF54 fusion protein and the c18orf54 specific polyclonal antibody will be valuable tools for the investigation on the biological function of C18ORF54.

Key words: hepatitis B virus, c18orf54, cell cycle, pathogenesis