Objective    To screen highly immunogenic fragment of human zinc transporter 8 (ZnT8) and to identify its expression in prokaryotic system.      Methods    Characteristics of ZnT8 structure were detected using bioinformatics software. A highly immunogenic fragment of ZnT8 was screened at the N-terminal and amplified by polymerase chain reaction (PCR）. Expression plasmid pET32a-ZnT8（N）was constructed and transformed to E.coli BL21(DE3). Expression of target protein was induced by isopropyl β-D-1-Thiogalactopyranoside（IPTG）. Expressed products were analyzed using SDS-PAGE and identified by Weste

rn blotting.     Results    The screened ZnT8 (N) fragment had 140 amino acids. Recombinant pET32a-ZnT8 (N) was successfully constructed

which was confirmed by restriction analysis. The relative molecular weight of expressed products was about 32×10

3

after transformed into E.coli

which was consistent with the expected value. Western blot analysis showed that the positively expressed products contained over 45% of the total fused protein.     Conclusion    A highly immunogenic fragment of ZnT8 can be screened from human islet cells

which is expressed in the prokaryotic system.