All members of the RAR family of nuclear receptor interact with members of the RXR family to form heterodimers that bind DNA with high affinity. Interactions between the DNA binding domain are sufficient to confer selectivity of DNA binding.^[1] The ligand binding domains of RARs interact with a variety of transcriptional coregulators. Corepressors NCoR and SMRT are bound in the absence of ligand while other corepressors such as NRIP1 and LCoR can be bound in the presence of ligand. Ligand also induces recruitment of coactivators, including histone acetyl-transferases NCOA1/2/3 and CBP/p300, histone methyl-transferases, ATP-dependent chromatin remodeling complexes, and of components of the mediator complex and basal transcription machinery.^[2][3][4]. In addition, RARs interact with other transcription factors such as the AP1 complex, enabling recruitment of RARs to DNA via tethering and possibly formation of chromatin loops between RARs and other transcription factors bound to the promoter/enhancers of RA target genes.