Transforming Growth Factor-β1 Negatively Regulates Crystallin Expression in Teeth†

Previously, we have reported that targeted overexpression of transforming growth factor (TGF) β1 in the teeth of the transgenic mice (dTGF-β1) results in a novel tooth phenotype phenomimicking the most prevalent tooth disorders in human. This phenotype was associated with discoloration and attrition of teeth due to defective mineralization. Here, we report a novel expression of crystallin family members in developing mouse teeth and its regulation by TGF-β1 in these transgenic mice. αB- and β-crystallins were found to be elevated in dTGF-β1 mouse teeth, whereas γ-crystallin (γB, γC, and γF), a marker of cell differentiation, was significantly reduced. Because crystallins are believed to be stress-related proteins, their expression in teeth implicates them in a similar role because teeth are constantly subjected to physical friction and temperature fluctuations.