Rational Design of Vitamin D3 Analogues Which Selectively Restore Activity to a Vitamin D Receptor Mutant Associated with Rickets

Abstract
Vitamin D3-resistant rickets (VDRR) is associated with mutations to the Vitamin D receptor (VDR) which effect ligand-dependent transactivation. Some VDRR associated mutants directly disrupt ligand binding. Using the reported VDR-1,25-dihydroxy vitamin D3 (1,25(OH)2D3) cocrystal structure, three 1,25(OH)2D3 analogues were designed to uniquely complement the rickets associated mutant VDR(Arg274→Leu). The three analogues were 17 to 286 times more potent than 1,25(OH)2D3 with the mutant in cell-based assays and did not substantially activate cellular calcium influx.