OBJECTIVETo evaluate the expression of dental matrix protein-l (DMP1) in porcine oral mucosa fibroblasts (POMF) transfected by DMP1 and the influences of the transfection.

METHODSThe full length of porcine DMP1 cDNA was linked into an eukaryotic expression vector pEGFP-C1. POMF and mesenchymal stem cells (MSC) were transfected with the pEGFP-DMP1. The expression of DMP1, dental sialoprotein (DSP), amelin and ameloblastin (Ambn) gene of transfected POMF and MSC were detected by RT-PCR. The expression of DMP1 and DSP protein was examined by immunocytochemical staining. The formation ratio of mineralized nodules of transfected cells was compared with un-transfected ones after mineralized induction. The formation of mineralized nodules of three-dimensional pellet transfected cells was compared with un-transfected ones after hematoxylin and eosin staining.

RESULTSThe constructed pEGFP-DMP1 could produce 4.7 kb and 1.5 kb fragments. DMP1 gene, DSP gene and Ambn gene were expressed by POMF after transfection. Immunohistochemical staining and the quantitative analysis of protein showed that DMP1 and DSP protein was positive in transfected POMF and MSC. The formation ratio of mineralized nodules of transfected POMF and MSC was higher than that of un-transfected ones (P < 0.05).

CONCLUSIONSThe expression of porcine DMP1 in POME after gene transfection can induce the expression of tooth-development-associated gene Ambn and DSP and enhance the formation of mineralized nodules.