Tooth and bone specimen require extensive demineralization for careful analysis of cell morphology, as well as gene and
protein expression levels. The LacZ gene, which encodes the ß-
galactosidase enzyme, is often used as a reporter gene to study gene-structure function, tissue-specific expression by a promoter, cell lineage and fate. This reporter gene is particularly useful for analyzing the spatial and temporal gene expression pattern, by expressing the LacZ gene under the control of a promoter of interest. To analyze LacZ activity, and the expression of other genes and their
protein products in teeth and bones, it is necessary to carry out a complete demineralization of the specimen before cutting sections. However, strong
acids, such as
formic acid used for
tooth demineralization, destroy the activities of
enzymes including those of ß-
galactosidase. Therefore, most protocols currently use mild
acids such as 0.1 M
ethylene diamine tetra-
acetic acid (
EDTA) for demineralization of tooth and bone specimen, which require a longer period of treatment for complete demineralization. A method by which hard tissue specimens such as teeth and bones can be rapidly, but gently, decalcified is necessary to save time and effort. Here, we report a suitable method for rapid demineralization of mouse teeth in 0.1M
EDTA at 42˚C without any loss of ß-
galactosidase activity.