Corticotropin-releasing hormone receptor 1

Corticotropin-releasing hormone receptor 1 (CRHR1) is a protein, also known as CRF1, with the latter (CRF1) now being the IUPHAR-recommended name.[4] In humans, CRF1 is encoded by the CRHR1 gene at region 17q21.31, beside micrototubule-associated protein tau MAPT.[5][6]

CRHR1
Available structures
PDBOrtholog search: PDBe RCSB
Identifiers
AliasesCRHR1, CRF-R, CRF-R-1, CRF-R1, CRF1, CRFR-1, CRFR1, CRH-R-1, CRH-R1, CRH-R1h, CRHR, CRHR1L, CRHR1f, corticotropin releasing hormone receptor 1
External IDsOMIM: 122561; MGI: 88498; HomoloGene: 20920; GeneCards: CRHR1; OMA:CRHR1 - orthologs
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_007762
NM_001313928
NM_001313929

RefSeq (protein)

NP_001300857
NP_001300858
NP_031788

Location (UCSC)n/aChr 11: 104.02 – 104.07 Mb
PubMed search[2][3]
Wikidata
View/Edit HumanView/Edit Mouse

Structure

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The human CRHR1 gene contains 14 exons over 20 kb of DNA, and its full gene product is a peptide composed of 444 amino acids.[7] Excision of exon 6 yields in the mRNA for the primary functional CRF1,[7] which is a peptide composed of 415 amino acids, arranged in seven hydrophobic alpha-helices.[8][9]

The CRHR1 gene is alternatively spliced into a series of variants.[7][10] These variants are generated through deletion of one of the 14 exons, which in some cases causes a frame-shift in the open reading frame, and encode corresponding isoforms of CRF1.[7][9] Though these isoforms have not been identified in native tissues, the mutations of the splice variants of mRNA suggest the existence of alternate CRF receptors, with differences in intracellular loops or deletions in N-terminus or transmembrane domains.[9] Such structural changes suggest that the alternate CRF1 receptors have different degrees of capacity and efficiency in binding CRF and its agonists.[7][9][10] Though the functions of these CRF1 receptors is yet unknown, they are suspected to be biologically significant.[9]

CRF1 is 70% homologous with the second human CRF receptor family, CRF2; the greatest divergence between the two lies at the N-terminus of the protein.[7][9]

Mechanism of activation

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CRF1 is activated through the binding of CRF or a CRF-agonist.[7][8][9] The ligand binding and subsequent receptor conformational change depends on three different sites in the second and third extracellular domains of CRF1.[9]

In the majority of tissues, CRF1 is coupled to a stimulatory G-protein that activates the adenylyl cyclase signaling pathway, and ligand-binding triggers an increase in cAMP levels.[7][9] However, the signal can be transmitted along multiple signal transduction cascades, according to the structure of the receptor and the region of its expression.[9] Alternate signaling pathways activated by CRF1 include PKC and MAPK.[7] This wide variety of cascades suggests that CRF1 mediates tissue-specific responses to CRF and CRF-agonists.[7][9]

Tissue distribution

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CRF1 is expressed widely throughout both the central and peripheral nervous systems.[9] In the central nervous system, CRF1 is particularly found in the cortex, cerebellum, amygdala, hippocampus, olfactory bulb, ventral tegmental area, brainstem areas, paraventricular hypothalamus, and pituitary.[11][7][8][12] In the pituitary, CRF1 stimulation triggers the activation of the POMC gene, which in turn causes the release of ACTH and β-endorphins from the anterior pituitary.[7] In the peripheral nervous system, CRF1 is expressed at low levels in a wide variety of tissues, including the skin, spleen, heart, liver, adipose tissue, placenta, ovary, testis, and adrenal gland.[7][8][10]

In CRF1 knockout mice, and mice treated with a CRF1 antagonist, there is a decrease in anxious behavior and a blunted stress response, suggesting that CRF1 mechanisms are anxiogenic.[7][12] However, the effect of CRF1 appears to be regionally specific and cell-type specific, likely due to the wide variety of cascades and signaling pathways activated by the binding of CRF or CRF-agonists.[12] In mice, offspring born to CRF1 -/- knockout mothers typically die within a few days of birth from lung dysplasia, likely due to low glucocorticoid levels.[13] In the central nervous system, CRF1 activation mediates fear learning and consolidation in the extended amygdala, stress-related modulation of memory formation in the hippocampus, and brainstem regulation of arousal.[12]

Function

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The corticotropin-releasing hormone receptor binds corticotropin-releasing hormone, a potent mediator of endocrine, autonomic, behavioral, and immune responses to stress.[14]

CRF1 receptors in mice mediate ethanol enhancement of GABAergic synaptic transmission.[15]

Postpartum function

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Postpartum CRF1 knockout mice spend less time nursing and less time licking and grooming their offspring than their wildtype counterparts during the first few days postpartum.[13] These pups weighed less as a result. This pattern of maternal behavior indicates that CRF1 may be needed for early postpartum mothers to display typical mothering behaviors. Maternal aggression is attenuated by increases in CRF and urocortin 2, which bind to CRF1.[16]

Evolution

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Corticotrophin releasing hormone (CRH) evolved ~500 million years ago in an organism that subsequently gave rise to both chordates and arthropods.[17] The binding site for this was single CRH like receptor. In vertebrates this gene was duplicated leading to the extant CRH1 and CRH2 forms. Additionally four paralogous ligands developed including CRH, urotensin-1/urocortin, urocortin II and urocortin III.

Clinical significance

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Variations in the CRHR1 gene is associated with enhanced response to inhaled corticosteroid therapy in asthma.[18]

CRF1 triggers cells to release hormones that are linked to stress and anxiety [original reference missing]. Hence CRF1 receptor antagonists are being actively studied as possible treatments for depression and anxiety.[19][20]

Variations in CRHR1 are associated with persistent pulmonary hypertension of the newborn.[21]

Interactions

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Corticotropin-releasing hormone receptor 1 has been shown to interact with Corticotropin-releasing hormone[9][22] and urocortin.[23]

See also

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References

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  1. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000018634Ensembl, May 2017
  2. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  3. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ Hauger RL, Grigoriadis DE, Dallman MF, Plotsky PM, Vale WW, Dautzenberg FM (March 2003). "International Union of Pharmacology. XXXVI. Current status of the nomenclature for receptors for corticotropin-releasing factor and their ligands". Pharmacological Reviews. 55 (1): 21–6. doi:10.1124/pr.55.1.3. PMID 12615952. S2CID 1572317.
  5. ^ Polymeropoulos MH, Torres R, Yanovski JA, Chandrasekharappa SC, Ledbetter DH (July 1995). "The human corticotropin-releasing factor receptor (CRHR) gene maps to chromosome 17q12-q22". Genomics. 28 (1): 123–4. doi:10.1006/geno.1995.1118. PMID 7590738.
  6. ^ Chen R, Lewis KA, Perrin MH, Vale WW (October 1993). "Expression cloning of a human corticotropin-releasing-factor receptor". Proceedings of the National Academy of Sciences of the United States of America. 90 (19): 8967–71. Bibcode:1993PNAS...90.8967C. doi:10.1073/pnas.90.19.8967. PMC 47482. PMID 7692441.
  7. ^ a b c d e f g h i j k l m n Hillhouse EW, Grammatopoulos DK (May 2006). "The molecular mechanisms underlying the regulation of the biological activity of corticotropin-releasing hormone receptors: implications for physiology and pathophysiology". Endocrine Reviews. 27 (3): 260–86. doi:10.1210/er.2005-0034. PMID 16484629.
  8. ^ a b c d Hauger RL, Grigoriadis DE, Dallman MF, Plotsky PM, Vale WW, Dautzenberg FM (March 2003). "International Union of Pharmacology. XXXVI. Current status of the nomenclature for receptors for corticotropin-releasing factor and their ligands". Pharmacological Reviews. 55 (1): 21–6. doi:10.1124/pr.55.1.3. PMID 12615952. S2CID 1572317.
  9. ^ a b c d e f g h i j k l m Grammatopoulos DK, Dai Y, Randeva HS, Levine MA, Karteris E, Easton AJ, Hillhouse EW (December 1999). "A novel spliced variant of the type 1 corticotropin-releasing hormone receptor with a deletion in the seventh transmembrane domain present in the human pregnant term myometrium and fetal membranes". Molecular Endocrinology. 13 (12): 2189–202. doi:10.1210/mend.13.12.0391. PMID 10598591.
  10. ^ a b c Paschos KA, Chouridou E, Koureta M, Lambropoulou M, Kolios G, Chatzaki E (April 2013). "The corticotropin releasing factor system in the liver: expression, actions and possible implications in hepatic physiology and pathology". Hormones. 12 (2): 236–45. doi:10.14310/horm.2002.1407. PMID 23933692.
  11. ^ Rosinger ZJ, Jacobskind JS, De Guzman RM, Justice NJ, Zuloaga DG (June 2019). "A sexually dimorphic distribution of corticotropin-releasing factor receptor 1 in the paraventricular hypothalamus". Neuroscience. 409: 195–203. doi:10.1016/j.neuroscience.2019.04.045. PMC 6897333. PMID 31055007.
  12. ^ a b c d Henckens MJ, Deussing JM, Chen A (October 2016). "Region-specific roles of the corticotropin-releasing factor-urocortin system in stress". Nature Reviews. Neuroscience. 17 (10): 636–51. doi:10.1038/nrn.2016.94. PMID 27586075. S2CID 5028285.
  13. ^ a b Gammie SC, Bethea ED, Stevenson SA (March 2007). "Altered maternal profiles in corticotropin-releasing factor receptor 1 deficient mice". BMC Neuroscience. 8: 17. doi:10.1186/1471-2202-8-17. PMC 1821036. PMID 17331244.
  14. ^ "Entrez Gene: CRHR1 corticotropin releasing hormone receptor 1".
  15. ^ Nie Z, Schweitzer P, Roberts AJ, Madamba SG, Moore SD, Siggins GR (March 2004). "Ethanol augments GABAergic transmission in the central amygdala via CRF1 receptors". Science. 303 (5663): 1512–4. Bibcode:2004Sci...303.1512N. doi:10.1126/science.1092550. PMID 15001778. S2CID 7312138.
  16. ^ D'Anna KL, Gammie SC (April 2009). "Activation of corticotropin-releasing factor receptor 2 in lateral septum negatively regulates maternal defense". Behavioral Neuroscience. 123 (2): 356–68. doi:10.1037/a0014987. PMID 19331459.
  17. ^ Lovejoy D, Chang B, Lovejoy N, Del Castillo J (2014) Origin and functional evolution of the corticotrophin-releasing hormone receptors. J Mol Endocrinol
  18. ^ Tantisira KG, Lake S, Silverman ES, Palmer LJ, Lazarus R, Silverman EK, Liggett SB, Gelfand EW, Rosenwasser LJ, Richter B, Israel E, Wechsler M, Gabriel S, Altshuler D, Lander E, Drazen J, Weiss ST (July 2004). "Corticosteroid pharmacogenetics: association of sequence variants in CRHR1 with improved lung function in asthmatics treated with inhaled corticosteroids". Human Molecular Genetics. 13 (13): 1353–9. doi:10.1093/hmg/ddh149. PMID 15128701.
  19. ^ Kehne JH (June 2007). "The CRF1 receptor, a novel target for the treatment of depression, anxiety, and stress-related disorders". CNS & Neurological Disorders Drug Targets. 6 (3): 163–82. doi:10.2174/187152707780619344. PMID 17511614.
  20. ^ Ising M, Holsboer F (December 2007). "CRH-sub-1 receptor antagonists for the treatment of depression and anxiety". Experimental and Clinical Psychopharmacology. 15 (6): 519–28. doi:10.1037/1064-1297.15.6.519. PMID 18179304.
  21. ^ Byers HM, Dagle JM, Klein JM, Ryckman KK, McDonald EL, Murray JC, Borowski KS (February 2012). "Variations in CRHR1 are associated with persistent pulmonary hypertension of the newborn". Pediatric Research. 71 (2): 162–7. doi:10.1038/pr.2011.24. PMC 3718388. PMID 22258127.
  22. ^ Gottowik J, Goetschy V, Henriot S, Kitas E, Fluhman B, Clerc RG, Moreau JL, Monsma FJ, Kilpatrick GJ (October 1997). "Labelling of CRF1 and CRF2 receptors using the novel radioligand, [3H]-urocortin". Neuropharmacology. 36 (10): 1439–46. doi:10.1016/S0028-3908(97)00098-1. PMID 9423932. S2CID 6235036.
  23. ^ Donaldson CJ, Sutton SW, Perrin MH, Corrigan AZ, Lewis KA, Rivier JE, Vaughan JM, Vale WW (May 1996). "Cloning and characterization of human urocortin". Endocrinology. 137 (5): 2167–70. doi:10.1210/endo.137.5.8612563. PMID 8612563.

Further reading

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