Retinoic acid receptor (RAR) (RAR)

Retinoic acid receptors (RARs) are members of the nuclear receptor superfamily that function as ligand-dependent transcription factors (UniProt: P10276). There are three main subtypes—RAR-alpha, RAR-beta, and RAR-gamma—which form heterodimers with Retinoid X Receptors (RXRs) to regulate gene expression by binding to Retinoic Acid Response Elements (RAREs) (PubMed: 25118642). RARs are essential for mediating the effects of Vitamin A derivatives on embryonic development, cell differentiation, and immune function (NIH: PMC3478244). In oncology, the PML-RARA fusion protein is a critical driver of acute promyelocytic leukemia (APL), making RAR-alpha a primary target for differentiation therapy using all-trans retinoic acid (ATRA) (StatPearls: NBK541039). In dermatology, RAR-selective agonists like adapalene and trifarotene are used to treat acne and psoriasis by modulating keratinocyte proliferation and inflammation (PubChem: CID 60164). However, systemic use of RAR ligands is strictly limited by their potent teratogenicity and potential for inducing differentiation syndrome in leukemia patients (PubMed: 11511608).

Other names

NR1BRetinoic acid receptor alphaRetinoic acid receptor betaRetinoic acid receptor gammaRAR-alphaRAR-betaRAR-gammaNuclear receptor subfamily 1 group B member 1Nuclear receptor subfamily 1 group B member 2Nuclear receptor subfamily 1 group B member 3

RARs function as ligand-activated transcription factors. Upon binding of an agonist such as all-trans retinoic acid, RARs undergo a conformational change that facilitates heterodimerization with Retinoid X Receptors (RXRs). This complex binds to specific DNA sequences known as Retinoic Acid Response Elements (RAREs), leading to the release of co-repressors and the recruitment of co-activators and RNA polymerase II to initiate the transcription of genes involved in cell differentiation and growth arrest (UniProt: P10276; PubMed: 25118642).