Alpha-2B adrenergic receptor

Adrenergic, alpha-2B-, receptor
Identifiers
Symbols ADRA2B; ADRA2L1; ADRA2RL1; ADRARL1; ALPHA2BAR
External IDs OMIM: 104260 MGI: 87935 HomoloGene: 553 IUPHAR: α2B-adrenoceptor GeneCards: ADRA2B Gene
Orthologs
Species Human Mouse
Entrez 151 11552
Ensembl ENSG00000222040 ENSMUSG00000058620
UniProt P18089 P30545
RefSeq (mRNA) NM_000682 NM_009633.3
RefSeq (protein) NP_000673 NP_033763.2
Location (UCSC) Chr 2:
96.78 – 96.78 Mb		 Chr 2:
127.19 – 127.19 Mb
PubMed search [1] [2]

The alpha-2B adrenergic receptor (α2B adrenoceptor), is a G-protein coupled receptor. It is a subtype of the adrenergic receptor family. The human gene encoding this receptor has the symbol ADRA2B.[1] ADRA2B orthologs[2] have been identified in several mammals.

Contents

Receptor

Alpha-2-adrenergic receptors include 3 highly homologous subtypes: alpha2A, alpha2B, and alpha2C. These receptors have a critical role in regulating neurotransmitter release from sympathetic nerves and from adrenergic neurons in the central nervous system.

Gene

This gene encodes the alpha2B subtype, which was observed to associate with eIF-2B, a guanine nucleotide exchange protein that functions in regulation of translation. A polymorphic variant of the alpha2B subtype, which lacks 3 glutamic acids from a glutamic acid repeat element, was identified to have decreased G protein-coupled receptor kinase-mediated phosphorylation and desensitization; this polymorphic form is also associated with reduced basal metabolic rate in obese subjects and may therefore contribute to the pathogenesis of obesity. This gene contains no introns in either its coding or untranslated sequences.[1]

A deletion variant of the alpha-2B adrenergic receptor has been shown to be related to emotional memory in Europeans and Africans.[3]

Evolution

The ADRA2B gene (sometimes referenced as A2AB) is used in animals as a nuclear DNA phylogenetic marker.[2] This intronless gene has first been used to explore the phylogeny of the major groups of mammals,[4] and contributed to reveal that placental orders are distributed into four major clades: Xenarthra, Afrotheria, Laurasiatheria, and Euarchonta plus Glires. Comparative analysis of the primary protein sequence of ADRA2B across placentals also showed the high conservation of residues thought to be involved in agonist binding and in G protein–coupling. However, great variations are observed in the very long, third intracellular loop, with a polyglutamyl domain displaying pervasive length differences in length.[5]

Selective Ligands

Antagonists

See also

References

  1. ^ a b "Entrez Gene: ADRA2B adrenergic, alpha-2B-, receptor". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=151. 
  2. ^ a b "OrthoMaM phylogenetic marker: ADRA2B coding sequence". http://www.orthomam.univ-montp2.fr/orthomam/data/cds/detailMarkers/ENSG00000222040_ADRA2B.xml. 
  3. ^ de Quervain DJ, Kolassa IT, Ertl V, Onyut PL, Neuner F, Elbert T, Papassotiropoulos A (September 2007). "A deletion variant of the alpha2b-adrenoceptor is related to emotional memory in Europeans and Africans". Nat. Neurosci. 10 (9): 1137–9. doi:10.1038/nn1945. PMID 17660814. 
  4. ^ Madsen O, Scally M, Douady CJ, Kao DJ, DeBry RW, Adkins R, Amrine HM, Stanhope MJ, de Jong WW, Springer MS (February 2001). "Parallel adaptive radiations in two major clades of placental mammals". Nature 409 (6820): 610–4. doi:10.1038/35054544. PMID 11214318. 
  5. ^ Madsen O, Willemsen D, Ursing BM, Arnason U, de Jong WW (December 2002). "Molecular evolution of the mammalian alpha 2B adrenergic receptor". Mol. Biol. Evol. 19 (12): 2150–60. PMID 12446807. 

Further reading

External links