Nestin expression is differently regulated between odontoblasts and the subodontoblastic layer in mice

AbstractTheNestin gene encodes type VI intermediate filament and is known to be expressed in undifferentiated cells during neurogenesis and myogenesis. To regulateNestin expression, the first or second intron enhancer is activated in a tissue-dependent manner, for example, the former in mesodermal cells and the latter in neural stem cells. AlthoughNestin has also been used as a differentiation marker for odontoblasts during tooth development, howNestin expression is regulated in odontoblasts remains unclear. Therefore, this study aimed to compare the expression patterns ofNestin-GFP (green fluorescent protein) with that of endogenous Nestin in developing teeth ofNestin-EGFP (enhanced GFP) transgenic mice, in which the second intron enhancer is connected with theEGFP domain, at postnatal 7d, 3w, and 8w. Immunohistochemical and in situ hybridization analyses revealed that endogenous Nestin protein andNestin mRNA were intensely expressed in differentiated odontoblasts, while GFP immunoreactivity, which reflects the activity ofNestin second intron enhancer-mediated transcription, was mainly observed in the subodontoblastic layer. These results indicate that the first intron enhancer may be activated in differentiated odontoblasts. Intriguingly,Nestin-GFP expression in the subodontoblastic layer was found to be restricted to the coronal pulp of molars, which is susceptible to tooth injuries. Because the subodontoblastic layer serves as a reservoir of newly differentiated odontobla...
Source: Histochemistry and Cell Biology - Category: Biomedical Science Source Type: research