Localization of profilaggrin mRNA in newborn rat skin by in situ hybridization.

Profilaggrin mRNA has been localized in newborn rat skin by in situ hybridization. The granular layer and the hair canals of the epidermis are strongly positive for profilaggrin mRNA, while the basal and spinous cell layers are negative. These results suggest that profilaggrin gene expression is under transcriptional regulation since profilaggrin protein detected by immunohistochemistry closely corresponds to the distribution of profilaggrin mRNA. In addition, our results suggest that the profilaggrin gene is not coordinately expressed with the genes specifying the differentiation-specific keratins.