Trace amine-associated receptor

Trace amine-associated receptor

Trace amine-associated receptors, abbreviated TAAR and otherwise known as trace amine receptors, abbreviated TAR or TA, are a class of G protein-coupled receptors identified in 2001.[1][2][3]

TAAR1 has gained considerable interest in academic and pharmaceutical industry research as endogenous receptors for trace amines, which are non-classical metabolic derivatives of phenylalanine and tryptophan and the psychostimulants amphetamine and methamphetamine.[3][4][5][6][7][8]

In 2004 it was shown that in mammals TAAR1 is probably also a receptor for thyronamines, decarboxylated and deiodinated metabolites of the thyroid hormones,[4] while the mouse mTAAR2 – mTAAR9 receptors are most probably olfactory receptors for volatile amines.[9][10]

Contents

  • Animal TAAR complement 1
  • Receptor function and ligands 2
  • See also 3
  • External links 4
  • References 5

Animal TAAR complement

The following is a list of the TAARs contained in selected animal genomes:[1][11]

Receptor function and ligands

HumanTAARs and their ligands
Group Naming
convention 		Prior names Known or putative function in humans[13] Known ligands References
Group 1 TAAR1 TA1  • Neuromodulation of biogenic amines in the CNS
 • Chemotaxis of leukocytes
 • Chemoreceptor for volatile odorants† 		 • Trace amines (e.g., phenethylamine, N-methylphenethylamine)
 • Classical monoamines (e.g., dopamine, serotonin, histamine)
 • Substituted amphetamines (e.g., amphetamine)
 [14][15][16]
Group 1 TAAR2‡ GPR58  • Chemotaxis of leukocytes
 • Chemoreceptor for volatile odorants 		phenethylamine, tyramine, 3-iodothyronamine [15][16]
Group 1 TAAR3 GPR57, GPR57P Probably a pseudogene [12][15]
Group 1 TAAR4 – Not present in humans [15][17]
Group 2 TAAR5 PNR Chemoreceptor for volatile and foul odorants trimethylamine, N,N-dimethylethylamine (agonists)
3-iodothyronamine (inverse agonist) 		[15][17][18][19][20]
Group 3 TAAR6 – Chemoreceptor for volatile odorants [15][17]
Group 3 TAAR7 – Not present in humans [15][17]
Group 3 TAAR8 TA5, TRAR5,
TAR5, GPR102 		Chemoreceptor for volatile odorants
(Note: only known Gi/o-coupled TAAR) 		[15][17][21]
Group 3 TAAR9‡ TA3, TRAR3,
TAR3 		Chemoreceptor for volatile odorants [15][17]
†TAAR1 is not expressed in the human olfactory epithelium, but certain volatile odorants have been identified as agonists of hTAAR1;[22] hence, it's not an olfactory receptor in spite of its capacity for odorant detection.[22]
‡TAAR2 is inactive in a subset of the human population, as there is a polymorphism with a premature stop codon in 10–15% of Asians.[12]
‡TAAR9 is a functional receptor in most of the population, but has a polymorphism with a premature stop codon in 10–30%, depending on the population subgroup.[12]

See also

External links

References

  1. ^ a b
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  12. ^ a b c d
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  15. ^ a b c d e f g h i
  16. ^ a b
  17. ^ a b c d e f
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  22. ^ a b
TAAR ligands in humans
TAAR1
Agonists
Endogenous†
Synthetic‡
Antagonists
TAAR2
Agonists‡
Antagonists
  •  
TAAR5
Agonists‡
Antagonists‡
†References for all endogenous human TAAR1 ligands are provided at List of trace amines

‡References for synthetic TAAR1 agonists can be found at TAAR1 or in the associated compound articles. For TAAR2 and TAAR5 agonists and antagonists, see TAAR for references.