RARA
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1DKF, 1DSZ, 3A9E, 3KMR, 3KMZ, 4DQM, 5K13
Identifiers
Aliases	RARA, NR1B1, RAR, retinoic acid receptor alpha, RARalpha
External IDs	OMIM: 180240 MGI: 97856 HomoloGene: 20262 GeneCards: RARA
Gene location (Human) Chr. Chromosome 17 (human)[1] Band 17q21.2 Start 40,309,180 bp[1] End 40,357,643 bp[1]
Gene location (Mouse) Chr. Chromosome 11 (mouse)[2] Band 11 D|11 62.76 cM Start 98,818,644 bp[2] End 98,865,768 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in lactiferous duct monocyte blood gallbladder right lung left uterine tube upper lobe of left lung canal of the cervix right coronary artery gastrocnemius muscle Top expressed in lip yolk sac spermatocyte spermatid molar female urethra organ of Corti male urethra neural tube aortic valve More reference expression data BioGPS More reference expression data
Gene ontology Molecular function retinoic acid binding transcription corepressor activity protein domain specific binding DNA-binding transcription factor activity nuclear receptor activity mRNA 5'-UTR binding signaling receptor binding RNA polymerase II transcription regulatory region sequence-specific DNA binding retinoic acid-responsive element binding transcription factor binding metal ion binding steroid hormone receptor activity enzyme binding zinc ion binding protein binding DNA binding sequence-specific DNA binding transcription coactivator activity protein kinase A binding protein kinase B binding translation repressor activity, mRNA regulatory element binding alpha-actinin binding protein heterodimerization activity chromatin DNA binding DNA-binding transcription factor activity, RNA polymerase II-specific histone deacetylase binding transcription cis-regulatory region binding nuclear receptor coactivator activity signaling receptor activity Cellular component cytoplasm actin cytoskeleton perinuclear region of cytoplasm neuron projection nucleus cell surface nucleoplasm neuronal cell body dendrite cytosol RNA polymerase II transcription regulator complex Biological process growth plate cartilage development germ cell development cellular response to retinoic acid ureteric bud development positive regulation of interleukin-5 production prostate gland development limb development apoptotic cell clearance chondroblast differentiation regulation of granulocyte differentiation protein phosphorylation response to vitamin A face development spermatogenesis response to ethanol negative regulation of cell population proliferation steroid hormone mediated signaling pathway regulation of apoptotic process response to cytokine negative regulation of translation regulation of transcription, DNA-templated negative regulation of cell differentiation negative regulation of gene expression transcription, DNA-templated cellular response to estrogen stimulus positive regulation of transcription, DNA-templated positive regulation of cell cycle regulation of myelination positive regulation of neuron differentiation negative regulation of tumor necrosis factor production transcription initiation from RNA polymerase II promoter trachea cartilage development glandular epithelial cell development male gonad development negative regulation of cartilage development response to retinoic acid negative regulation of granulocyte differentiation multicellular organism growth female pregnancy negative regulation of apoptotic process negative regulation of transcription by RNA polymerase II positive regulation of interleukin-4 production regulation of synaptic plasticity outflow tract septum morphogenesis negative regulation of transcription, DNA-templated negative regulation of interferon-gamma production response to estradiol negative regulation of translational initiation embryonic camera-type eye development positive regulation of interleukin-13 production neural tube closure positive regulation of binding retinoic acid receptor signaling pathway positive regulation of gene expression Sertoli cell fate commitment positive regulation of cell population proliferation positive regulation of T-helper 2 cell differentiation ventricular cardiac muscle cell differentiation liver development cellular response to lipopolysaccharide bone development hippocampus development signal transduction positive regulation of transcription by RNA polymerase II multicellular organism development hormone-mediated signaling pathway cell differentiation response to lipid gland development bone morphogenesis epithelium development Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 5914 19401 Ensembl ENSG00000131759 ENSMUSG00000037992 UniProt P10276 Q6I9R7 P11416 RefSeq (mRNA) NM_000964 NM_001024809 NM_001033603 NM_001145301 NM_001145302 NM_001176528 NM_001177302 NM_001177303 NM_009024 NM_001361954 RefSeq (protein) NP_000955 NP_001019980 NP_001138773 NP_001138774 NP_000955.1 NP_001138773.1 NP_001169999 NP_001170773 NP_001170774 NP_033050 NP_001348883 Location (UCSC) Chr 17: 40.31 – 40.36 Mb Chr 11: 98.82 – 98.87 Mb PubMed search [3] [4]
Wikidata
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Retinoic acid receptor alpha (RAR-α), also known as NR1B1 (nuclear receptor subfamily 1, group B, member 1) is a nuclear receptor that in humans is encoded by the RARA gene.^[5][6]

NR1B1 is a gene with a protein product and has a chromosomal location of 17q21.2. RARA codes for the nuclear hormone receptor retinoic acid receptor, alpha subtype, a transcription factor. There are another two subtypes of RARs: beta and gamma subtypes.^[7][8]

Function

Retinoid signaling is transduced by 2 families of nuclear receptors, retinoic acid receptor (RAR) and retinoid X receptor (RXR), which form RXR/RAR heterodimers. In the absence of ligand, DNA-bound RXR/RARA represses transcription by recruiting the corepressors NCOR1, SMRT (NCOR2), and histone deacetylase. When ligand binds to the complex, it induces a conformational change allowing the recruitment of coactivators, histone acetyltransferases, and the basic transcription machinery.^[9]

Retinoic acid receptor-alpha, the protein, interacts with retinoic acid, a derivative of vitamin A, which plays an important role in cell growth, differentiation, and the formation of organs in embryonic development.^[8][10]

Once retinoic acid binds to the RAR, the heterodimer initiates transcription and allows for its target genes to be expressed. ^[10] 

Clinical significance

RA signaling has been correlated with several signaling pathways in early embryonic development. First, it participates in the formation of the embryonic axis, which establishes symmetry in the offspring. RA also influences neural differentiation by regulating the expression of pro-neural induction factor Neurogenin 2 (Neurog2). RA affects cardiogenesis, as it plays a role specifically in the formation of the atrial chambers of the heart. RA also plays a role in the development of the pancreas, kidneys, lungs, and extremities.  ^[10]

Translocations that always involve rearrangement of the RARA gene are a cardinal feature of acute promyelocytic leukemia (APL; MIM 612376). The most frequent translocation is t(15,17)(q21;q22), which fuses the RARA gene with the PML gene.^[11]

Acute promyeloid leukemia

RARA plays an important role in the establishment of the immune system by inducing T-regulatory cells, promoting tolerance, and controlling the differentiation of immature immune cells in the bone marrow called promyelocytes into mature white blood cells.^[12] The prevalence of this gene in the developing immune system leaves it subject to possible defects, the most common of which is a condition known as acute promyeloid leukemia (APL), caused by a somatic mutation described by the fusion of RARA and the PML gene located on chromosome 15.^[13] This fusion results in the formation of the protein complex PML-RARα. Under normal circumstances, PML produces a tumor suppressing protein that works by inhibiting uncontrolled rapid cell growth. When the two proteins fuse together, their normal functions are hindered, resulting in the accumulation of promyelocytes in the bone marrow unable to differentiate past this immature phase.^[14] This fusion makes up for the cause of 98% of APL cases, with some other rare mutations and fusions making up the other 2%.6 Current treatment approaches include all-trans-retinoic acid (ATRA) which works by targeting and degrading the PML-RARα protein complex, in addition to chemotherapy and platelet transfusions.^[15]

Interactions

Retinoic acid receptor alpha has been shown to interact with:

Genetic studies

Knock-out mice studies showed that a deletion in one of the copies of the RARA gene did not create any observable defect, while deletion of both copies shows symptoms similar to that of vitamin A deficiency. This proved that all 3 subtypes of RARs work redundantly.

Ligands

Antagonists

• BMS-189453 (non selective)
• YCT529 (selective for RAR-α)

See also

• Retinoic acid receptor
• Retinoic X Receptor
• Acute promyelocytic leukemia

References

Further reading

This article incorporates text from the United States National Library of Medicine, which is in the public domain.