Expression and function of DMT1 without IRE in C6 cells mediated by recombinant adenovirus

Divalent metal transporter 1 (DMT1) is a ferrous iron import protein. The improper expression of DMT1 is involved in neurodegenerative diseases. In the present study, we constructed a recombinant adenovirus containing the gene of DMT1 without the iron response element (DMT1-IRE) and investigated its expression and function in the C6 glioma cell line. The DMT1-IRE gene, obtained by RT-PCR, was cloned into the shuttle plasmiding pAdTrack-CMV containing green fluorescent protein (GFP) reporter gene. Linearized plasmid pAdTrack-CMV-DMT1-IRE was subsequently co-transformed into Escherichia coli (E. coli) BJ5183 cells along with an adenoviral backbone plasmid pAdEasy-1 after digestion with Pme I. PacI-digested pAdEasy1-DMT1-IRE was then transfected into E1-transformed human embryonic kidney cells (HEK293 cells), in which recombinant adenoviruses were generated within 7 to 10 days. The results demonstrated that we obtained the DMT1-IRE gene. pAdEasy1-DMT1-IRE yielded a large fragment, plus a smaller fragment of 4.5 kb after digestion with Pac I. PCR confirmed pAdEasy1-DMT1-IRE contained gene DMT1-IRE, indicating the successful construction of recombinant adenovirus plasmid containing DMT1-IRE. GFP fluorescence further confirmed the generation of recombinant AdDMT1-IRE adenovirus. AdDMT1-IRE could efficiently infect C6 glioma cells. And cell viability decreased in AdDMT1-IRE infected cells after iron overload compared to the control. These results suggest that the over expressed DMT1-IRE can aggravate the iron induced cell death due to its iron influx function.