Bioinformatics Database

Tan et al. (2017) analyzed Bmp2 expression in mice at embryonic day 12.5 and observed specific and strong staining in vibrissae follicles, facial and supraorbital dermis, Meckel cartilage, and embryonic dental epithelium. There was strong expression in the cartilaginous primordia of the appendicular and axial skeleton (limbs and ribs), and in the developing heart at the valves and ventricular-atrial junctions. During early tooth-germ development, MSX-1 becomes strongly expressed in mesenchyme at the lamina stage, achieves maximal expression during the cap stage. Msx1-deficient mice are characterized by arrest of tooth-germ development at the bud stage, along with decreased expression of bone morphogenetic protein 2 (Bmp2), bone morphogenetic protein 4 (Bmp4), lymphoid enhancer binding factor 1 (Lef1), and other downstream genes (Feng et al., 2018). Bmp2, Bmp4, and Lef1 are highly expressed in dental mesenchyme at late bell stage. Msx1 is strongly expressed in multiple undifferentiated organs during development and its expression decreases when the dental germ begins to undergo differentiation. Feng et al,( 2018) suggest that MSX-1 inhibits the expression of Bmp2, Bmp4, and Lef1 in order to prevent the premature and excessive differentiation of odontoblasts that might otherwise be caused by their increased expression.