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 (By similarity). Required for hindbrain development and for the development of pharyngeal arches. Heterodimer; with an rxr molecule. Binds DNA preferentially as a rar/rxr heterodimer. Expressed zygotically, with greatest expression at 24 hours post-fertilization (hpf). At 9 hpf, shows ubiquitous expression in the epiblast. At 10 hpf, expressed in anterior and posterior regions; not expressed in the presumptive hindbrain, and anterior expression is limited to mesoderm adjacent to the head. Between 11-15 hpf restricted expression in the cranial mesoderm and tailbud. At 12 hpf, expressed in anterior lateral mesenchyme, with strongest expression lateral to the future hindbrain, and in tailbud. At 24 hpf, also expressed in the hindbrain, neural crest cells and tail; not detected in spinal cord. At 48 hpf, hindbrain expression increases with an anterior border at rhombomere 3 and a posterior border at the spinal cord/hindbrain junction; expressed in stripes one rhombomere wide in dorsal hindbrain. At 48 hpf, also expressed in pharangeal arches 1-7, anterior neurocranium, cells separating the eyes and forebrain, pectoral fin buds and tailbud. Embryonic zygotic expression overlaps that of raraa and rarab, but there is stronger expression in the posterior hindbrain beginning in late somitogenesis, and in neural crest cells in the pharangeal arches. In the adult, strongly expressed in the ovary, brain and muscle, and weakly expressed in the liver and digestive tract. By retinoic acid, in embryonic anterior brain and eye. Composed of three domains: a modulating N-terminal domain, a DNA-binding domain and a C-terminal ligand-binding domain. Belongs to the nuclear hormone receptor family. NR1 subfamily.