Function
Retinoid X receptor (RXR) is a nuclear receptor activated by 9-cis retinoic acid. RXR makes a heterodimer with subfamily 1 nuclear receptors including retinoic acid receptor (RAR). In the absence of ligand, the RAR/RXR complex binds the hormone response elements complexed with corepressor protein. Upon binding of the ligand, the corepressor disassociates from the receptor and associates with the coactivator leading to transcription activation. RXR contains a DNA-binding domain (DBD) and ligand-binding domain (LBD)[1]. For additional details on RXR-α see RA Mediated T-reg Differentiation.
See also Intracellular receptors
There are 3 classes of RXR: α, β and γ.
- RXRα plays a pivotal role in liver metabolism[2].
- RXRγ mediates the anti proliferative effects of retinoid acid.
Relevance
RXRγ is involved in working memory and despair behavior[3]. RXR pathway is a positive regulator of myelin debris clearance and has a role in age-related decline in remyelination[4].
Structural highlights
. Hydrophobic, Polar. Water molecules are shown as red spheres. . The ligand-binding residues are conserved in the 3 classes of RXR
[5].
3D structures of retinoid X receptor
Retinoid X receptor 3D structures