The mechanisms regulating stem cell differentiation and self-renewal are largely unknown. Our ultimate goal is to be able to regulate somatic stem cell differentiation and proliferation, In the present study the ability of trans-differentiation was studied when different normal tissue types were transplanted into the duodenum in rats. Pieces of ear (skin), bladder, trachea, diaphragm, pyloric gland. and forestomach from 8-week old GFP-F344 rats were transplanted into the duodenum of F344 rats. Goblet cells with alcian-blue PAS positive mucin and brash border with alkaline phosphatase (ALP) activity appeared in tissues implanted into the duodenum. In addition, GFP-positive duodenal mucosa was observed in all cases by immunohistochemical staining. Moreover, the GFP-positive cells were found to carry the GFP transgene by PCR analysis. indicating that the bladder, trachea. ear (skin), diaphragm, pyloric gland, and farestomach tissues showed a multipotential ability for differentiation. These results indicated that stem cells within tissues have a multipotential ability, trans-differentiating into different organs when transplanted into different environments.