Mechanism of vitamin D3-induced transcription of phospholipase D1 in HaCat human keratinocytes.

1alpha,25-Dihydroxyvitamin D(3) (VitD(3)) increases protein and gene expression of phospholipase D1 (PLD1), but not PLD2, in HaCaT human keratinocytes. We show that VitD(3) increases PLD1 gene expression through a vitamin D responsive element (VDRE) on the 5' PLD1 promoter (-260 bp to -246 bp from exon 1). Similar results were obtained by transfecting VitD(3) receptor (VDR) into HEK293 cells, which are originally VitD(3)-unresponsive.