Relationship between Structure and Conformational Change of the Vitamin D Receptor Ligand Binding Domain in 1α,25-Dihydroxyvitamin D3 Signaling

Molecules. 2015 Nov 18;20(11):20473-86. doi: 10.3390/molecules201119713.

Abstract

Vitamin D Receptor (VDR) belongs to the nuclear receptor (NR) superfamily. Whereas the structure of the ligand binding domain (LBD) of VDR has been determined in great detail, the role of its amino acid residues in stabilizing the structure and ligand triggering conformational change is still under debate. There are 13 α-helices and one β-sheet in the VDR LBD and they form a three-layer sandwich structure stabilized by 10 residues. Thirty-six amino acid residues line the ligand binding pocket (LBP) and six of these residues have hydrogen-bonds linking with the ligand. In 1α,25-dihydroxyvitamin D₃ signaling, H3 and H12 play an important role in the course of conformational change resulting in the provision of interfaces for dimerization, coactivator (CoA), corepressor (CoR), and hTAFII 28. In this paper we provide a detailed description of the amino acid residues stabilizing the structure and taking part in conformational change of VDR LBD according to functional domains.

Keywords: conformational change; functional domains; ligand binding domain; structure basis; vitamin D receptor.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Humans
  • Hydrogen Bonding
  • Hydrophobic and Hydrophilic Interactions
  • Ligands
  • Models, Molecular*
  • Molecular Conformation*
  • Molecular Sequence Data
  • Protein Binding
  • Protein Interaction Domains and Motifs*
  • Receptors, Calcitriol / chemistry*
  • Receptors, Calcitriol / metabolism*
  • Sequence Alignment
  • Signal Transduction*
  • Structure-Activity Relationship
  • Vitamin D / analogs & derivatives*
  • Vitamin D / chemistry
  • Vitamin D / metabolism

Substances

  • Ligands
  • Receptors, Calcitriol
  • dihydroxy-vitamin D3
  • Vitamin D