Rev-ErbA alpha

Nuclear receptor subfamily 1, group D, member 1

The DNA binding domain of NR1D1 bound to double stranded DNA.[1]
Available structures
PDB Ortholog search: PDBe, RCSB
Identifiers
Symbols NR1D1 ; EAR1; THRA1; THRAL; ear-1; hRev
External IDs OMIM: 602408 MGI: 2444210 HomoloGene: 23324 IUPHAR: 596 GeneCards: NR1D1 Gene
RNA expression pattern
More reference expression data
Orthologs
Species Human Mouse
Entrez 9572 217166
Ensembl ENSG00000126368 ENSMUSG00000020889
UniProt P20393 Q3UV55
RefSeq (mRNA) NM_021724 NM_145434
RefSeq (protein) NP_068370 NP_663409
Location (UCSC) Chr 17:
40.09 – 40.1 Mb
Chr 11:
98.77 – 98.78 Mb
PubMed search

Rev-ErbA alpha also known as NR1D1 (nuclear receptor subfamily 1, group D, member 1), is a protein that in humans is encoded by the NR1D1 gene.[2]

Rev-erbα is member of the Rev-ErbA family of nuclear receptors and is a transcriptional repressor.[3] In mammals, Rev-erbα is highly expressed in the liver, skeletal muscle, adipose tissue, and the brain, participating in the development and circadian regulation of these tissues.[4][5]

Gene and protein structure

Rev-erbα is transcribed from the opposite strand of the thyroid receptor α (c-erbAα) gene on chromosome 17, with a 269-nucleotide overlap between the two transcripts.[3] The other mammalian isoform of the receptor, Rev-erbβ is encoded by another gene on chromosome 3. In addition, there is one non-mammalian homolog, the ecdysone-regulated gene E75, which is present in Drosophila and C. elegans. The Rev-erbα gene itself has multiple transcripts. Two promoters govern the expression of the Rev-erbα gene in human and rat, generating two mRNA isoforms. The full-length isoform encodes a 614-amino acid protein, while a second isoform is generated from an internal promoter and produces a protein that is shorter by 106 amino acids. Both Rev-erbα mRNA isoforms contain E-boxes as well as Rev-erbα response elements, which means that they can be regulated in a circadian manner by the BMAL and Rev-erba proteins. In fact, both transcripts exhibit rhythmic expression in serum-synchronized fibroblasts.

The Rev-erbα protein is structurally unique from other nuclear receptors, in that it lacks helix 12 (H12) in its ligand-binding domain, which is usually responsible for forming the ligand binding pocket in other nuclear receptors. In place of the missing H12, Rev-erbα displays a hydrophobic interface that binds the corepressor N-CoR, making it a potent transcriptional repressor.[6] Interestingly, all members of the Rev-erb family bind heme, which may act as a ligand to regulate their transcriptional activity.[7]

Physiologic function

Rev-erbα regulates gene transcription by directly binding to target response elements (RevREs), and comprises an A/T-rich flank followed by AGGTCA. Rev-erbα mediates repression by recruiting the corepressor N-CoR, which then activates the histone deacetylase (HDAC) 3. A number of target genes have been identified for Rev-erbα, including the lipoproteins ApoA1 and ApoCIII, hydratase dehydrogenase, the circadian factor BMAL, and the anti-fibrinolytic factor PAI-1.[8] Many of these genes are coordinately regulated by Rev-erbα and the RAR-related orphan receptor RORα, which share the same response elements but exert opposite effects on gene transcription. Crosstalk between Rev-erbα and RORα likely acts to fine-tune their target physiologic networks, such as circadian rhythms, metabolic homeostasis,[9] and inflammation.[10]

Rev-erbα mRNA is induced during adipogenesis and is highly expressed in adipose tissue.[11] One study reported that overexpression of Rev-erbα may enhance adipogenesis in cultured mouse adipocytes, but the mechanism of this effect remains to be elucidated.[12] More recently, a study showed that the deletion of Rev-erbα in mice alters glucose and lipid metabolism and leads to obesity.[13]

Rev-erbα expression is also regulated at the post-translational level: it is phosphorylated on the amino terminus by glycogen synthase kinase (GSK 3β), which contributes to its protein stability. It has been shown that lithium, which inhibits GSK3β, can de-stabilize Rev-erbα protein and affect its function in the circadian clock.[14] This may partly explain lithium’s therapeutic effect on circadian diseases such as bipolar disorder.

References

  1. PDB: 1a6yZhao Q, Khorasanizadeh S, Miyoshi Y, Lazar MA, Rastinejad F (May 1998). "Structural elements of an orphan nuclear receptor-DNA complex". Mol. Cell 1 (6): 849–61. doi:10.1016/S1097-2765(00)80084-2. PMID 9660968.
  2. Lazar MA, Jones KE, Chin WW (Mar 1990). "Isolation of a cDNA encoding human Rev-ErbA alpha: transcription from the noncoding DNA strand of a thyroid hormone receptor gene results in a related protein that does not bind thyroid hormone". DNA and Cell Biology 9 (2): 77–83. doi:10.1089/dna.1990.9.77. PMID 1971514.
  3. 1 2 Lazar MA, Hodin RA, Cardona G, Chin WW (Aug 1990). "Gene expression from the c-erbA alpha/Rev-ErbA alpha genomic locus. Potential regulation of alternative splicing by opposite strand transcription". The Journal of Biological Chemistry 265 (22): 12859–63. PMID 2165488.
  4. Preitner N, Damiola F, Lopez-Molina L, Zakany J, Duboule D, Albrecht U, Schibler U (Jul 2002). "The orphan nuclear receptor REV-ERBalpha controls circadian transcription within the positive limb of the mammalian circadian oscillator". Cell 110 (2): 251–60. doi:10.1016/S0092-8674(02)00825-5. PMID 12150932.
  5. Triqueneaux G, Thenot S, Kakizawa T, Antoch MP, Safi R, Takahashi JS, Delaunay F, Laudet V (Dec 2004). "The orphan receptor Rev-erbalpha gene is a target of the circadian clock pacemaker". Journal of Molecular Endocrinology 33 (3): 585–608. doi:10.1677/jme.1.01554. PMID 15591021.
  6. Woo EJ, Jeong DG, Lim MY, Jun Kim S, Kim KJ, Yoon SM, Park BC, Ryu SE (Oct 2007). "Structural insight into the constitutive repression function of the nuclear receptor Rev-erbbeta". Journal of Molecular Biology 373 (3): 735–44. doi:10.1016/j.jmb.2007.08.037. PMID 17870090.
  7. Raghuram S, Stayrook KR, Huang P, Rogers PM, Nosie AK, McClure DB, Burris LL, Khorasanizadeh S, Burris TP, Rastinejad F (Dec 2007). "Identification of heme as the ligand for the orphan nuclear receptors REV-ERBalpha and REV-ERBbeta". Nature Structural & Molecular Biology 14 (12): 1207–13. doi:10.1038/nsmb1344. PMC 2743565. PMID 18037887.
  8. Wang J, Yin L, Lazar MA (Nov 2006). "The orphan nuclear receptor Rev-erb alpha regulates circadian expression of plasminogen activator inhibitor type 1". The Journal of Biological Chemistry 281 (45): 33842–8. doi:10.1074/jbc.M607873200. PMID 16968709.
  9. Delezie J, Challet E (Dec 2011). "Interactions between metabolism and circadian clocks: reciprocal disturbances". Annals of the New York Academy of Sciences 1243: 30–46. doi:10.1111/j.1749-6632.2011.06246.x. PMID 22211891.
  10. Forman BM, Chen J, Blumberg B, Kliewer SA, Henshaw R, Ong ES, Evans RM (Sep 1994). "Cross-talk among ROR alpha 1 and the Rev-erb family of orphan nuclear receptors". Molecular Endocrinology 8 (9): 1253–61. doi:10.1210/me.8.9.1253. PMID 7838158.
  11. Fontaine C, Dubois G, Duguay Y, Helledie T, Vu-Dac N, Gervois P, Soncin F, Mandrup S, Fruchart JC, Fruchart-Najib J, Staels B (Sep 2003). "The orphan nuclear receptor Rev-Erbalpha is a peroxisome proliferator-activated receptor (PPAR) gamma target gene and promotes PPARgamma-induced adipocyte differentiation". The Journal of Biological Chemistry 278 (39): 37672–80. doi:10.1074/jbc.M304664200. PMID 12821652.
  12. Chawla A, Lazar MA (Aug 1993). "Induction of Rev-ErbA alpha, an orphan receptor encoded on the opposite strand of the alpha-thyroid hormone receptor gene, during adipocyte differentiation". The Journal of Biological Chemistry 268 (22): 16265–9. PMID 8344913.
  13. Delezie J, Dumont S, Dardente H, Oudart H, Gréchez-Cassiau A, Klosen P, Teboul M, Delaunay F, Pévet P, Challet E (Aug 2012). "The nuclear receptor REV-ERBα is required for the daily balance of carbohydrate and lipid metabolism". FASEB Journal 26 (8): 3321–35. doi:10.1096/fj.12-208751. PMID 22562834.
  14. Yin L, Wang J, Klein PS, Lazar MA (Feb 2006). "Nuclear receptor Rev-erbalpha is a critical lithium-sensitive component of the circadian clock". Science 311 (5763): 1002–5. doi:10.1126/science.1121613. PMID 16484495.

Further reading

External links

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