[3] There are three retinoic acid receptors (RAR), RAR-alpha, RAR-beta, and RAR-gamma, encoded by the RARA, RARB, RARG genes, respectively.
[1] Multiple splice variants have been identified in human RARs: four for RARA, five for RARB, and two for RARG.
[4] As with other type II nuclear receptors, RAR heterodimerizes with RXR and in the absence of ligand, the RAR/RXR dimer binds to hormone response elements known as retinoic acid response elements (RAREs) complexed with corepressor protein.
[5] Both the length and magnitude of the retinoid response is dependent of the degradation of RARs and RXRs through the ubiquitin-proteasome.
RXR/RAR heterodimers transmit retinoid signals in diverse ways to control the expression of networks of retinoic acid (RA) target genes.