Receptor for retinoic acid. Retinoic acid receptors bind as heterodimers to their target response elements in response to their ligands, all-trans or 9-cis retinoic acid, and regulate gene expression in various biological processes. The RAR/RXR heterodimers bind to the retinoic acid response elements (RARE) composed of tandem 5'-AGGTCA-3' sites known as DR1-DR5. In the absence of ligand, acts mainly as an activator of gene expression due to weak binding to corepressors (By similarity). Required for limb bud development. In concert with RARA or RARB, required for skeletal growth, matrix homeostasis and growth plate function. Homodimer (By similarity). Heterodimer with a RXR molecule (By similarity). Binds DNA preferentially as a RAR/RXR heterodimer (By similarity). Forms a complex with PUS1 and the SRA1 RNA in the nucleus. In 9.5-12.5 dpc embryos, expression throughout limb bud mesenchyme. This expression overlaps with that of CYP26B1. Also strongly expressed in the caudal and craniofacial regions. Composed of three domains: a modulating N-terminal domain, a DNA-binding domain and a C-terminal ligand-binding domain. Rarg and Rarb double null mice exhibit growth retardation 3 weeks after birth. Defects are found in the growth plates with deficiency in cartilage. Growth retardation was noticable in limb sketal elements such as femurs. Early lethality and male sterility due to squamous metaplasia of the seminal vesicles and prostate are also observed. Isoform 2 mutants appear normal. The Rarg and Cyp26b1 double null mutation is able to partially rescue limb skeletal morphology without restoring normal expression of proximo-distal patterning genes. Belongs to the nuclear hormone receptor family. NR1 subfamily.