Expression of nephronectin is enhanced by 1α,25‐dihydroxyvitamin D3

The extracellular matrix protein nephronectin (Npnt), also called POEM, is considered to play critical roles as an adhesion molecule in development and functions of various tissues, such as the kidneys, liver, and bone. In the present study, we examined the molecular mechanism of Npnt gene expression and found that vitamin D3 (1α,25-dihydroxyvitamin D3,VD3) strongly enhanced Npnt mRNA expression in MC3T3-E1 cells from a mouse osteoblastic cell line. The VD3-induced increase in Npnt expression is both time- and dose-dependent and is mediated by the vitamin D receptor (VDR).