BACKGROUND:It is reported that tailless-like protein (TLX) plays critical roles in the regulation of early developmental processes in vertebrates, and it plays a key role in stem cells proliferation and differentiation into neurons. OBJECTIVE: To construct recombinant plasmid pEGFPN1-TLX and study the transfection into dermal multipotential stem cells. DESIGN, TIME AND SETTING: Cytogene experiment was performed at the Department of Pathogen Biology, School of Basic Medical Science, the Third Military Medical University of Chinese PLA from March to December 2007. MATERIALS: An adult SD was obtained from the Experimental Animal Center of the Third Military Medical University of Chinese PLA; dermal moltipotential stem cells (DMSCs) were cultured by the Institute of Combined Injury of the Third Military Medical University of Chinese PLA; pEGFPN1 and DH5α was gifted by professor Xu.METHODS: Total RNA was extracted from rat brain tissue to amplify TLX-coded cDNA sequence using RT-PCR. T/A was cloned on pMD18-T vector and determined using BamHI and Hindlll. The products were positive recombinant plasmid pMD18-T-TLX segments, which were sub-cloned in pEGFPN1 to construct recombinant plasmid pEGFPN1-TLX. Finally, pEGFPN1-TLX was transfected into DMSCs.MAIN OUTCOME MEASURES: The fluorescence protein expression was observed under fluorescence microscope at 24 hours after transfection; TLX mRNA expression was detected using RT-PCR; neuronal differentiation was observed using immunohistochemical staining.RESULTS: TLX full length cDNA was successfully cloned into pEGFPN1, and pEGFPN1-TLX was successfully constructed by means of sequence analysis and enzyme cutting identification. As compared with non-transfected DMSCs, pEGFPN1-TLX transfected DMSCs were observed after 10 days, formed resistant clones after 15 days, and shown a green fluorescent protein expression. However, non-transfected DMSCs died at day 10. RT-PCR indicated that pEGFPN1-TLX transfected DMSCs could express TLX mRNA. At day 3 after induction, NF200 positive cells were increased, but glial fibrillary acidic protein positive cells were decreased after induction of pEGFPN1-TLX transfected DMSCs.CONCLUSION: TLX was successfully constructed and transfected into DMSCs. After transfection, neuronal differentiation of DMSCs was enhanced, and the differentiation to gliocytes was inhibited.