Substance-K receptor is a protein that in humans is encoded by the TACR2 gene. [5]
This gene belongs to a family of genes that function as receptors for tachykinins. Receptor affinities are specified by variations in the 5'-end of the sequence. The receptors belonging to this family are characterized by interactions with G proteins and 7 hydrophobic transmembrane regions. This gene encodes the receptor for the tachykinin neuropeptide substance K, also referred to as neurokinin A. [5]
Several selective ligands for NK2 are now available, and although most of the compounds developed so far are peptides, one small-molecule antagonist Saredutant is currently in clinical trials as an anxiolytic and antidepressant.
This article needs to be updated.(May 2022) |
Substance P (SP) is an undecapeptide and a type of neuropeptide, belonging to the tachykinin family of neuropeptides. It acts as a neurotransmitter and a neuromodulator. Substance P and the closely related neurokinin A (NKA) are produced from a polyprotein precursor after alternative splicing of the preprotachykinin A gene. The deduced amino acid sequence of substance P is as follows:
Tachykinin peptides are one of the largest families of neuropeptides, found from amphibians to mammals. They were so named due to their ability to rapidly induce contraction of gut tissue. The tachykinin family is characterized by a common C-terminal sequence, Phe-X-Gly-Leu-Met-NH2, where X is either an Aromatic or an Aliphatic amino acid. The genes that produce tachykinins encode precursor proteins called preprotachykinins, which are chopped apart into smaller peptides by posttranslational proteolytic processing. The genes also code for multiple splice forms that are made up of different sets of peptides.
Physalaemin is a tachykinin peptide obtained from the Physalaemus frog, closely related to substance P. Its structure was first elucidated in 1964.
There are three known mammalian tachykinin receptors termed NK1, NK2 and NK3. All are members of the 7 transmembrane G-protein coupled receptor family and induce the activation of phospholipase C, producing inositol triphosphate (so called Gq-coupled).
Kassinin is a peptide derived from the Kassina frog. It belongs to tachykinin family of neuropeptides. It is secreted as a defense response, and is involved in neuropeptide signalling.
Neurokinin 1 (NK1) antagonists (-pitants) are a novel class of medications that possesses unique antidepressant, anxiolytic, and antiemetic properties. NK-1 antagonists boost the efficacy of 5-HT3 antagonists to prevent nausea and vomiting. The discovery of neurokinin 1 (NK1) receptor antagonists was a turning point in the prevention of nausea and vomiting associated with cancer chemotherapy.
Neurokinin A (NKA), formerly known as Substance K, is a neurologically active peptide translated from the pre-protachykinin gene. Neurokinin A has many excitatory effects on mammalian nervous systems and is also influential on the mammalian inflammatory and pain responses.
The tachykinin receptor 1 (TACR1) also known as neurokinin 1 receptor (NK1R) or substance P receptor (SPR) is a G protein coupled receptor found in the central nervous system and peripheral nervous system. The endogenous ligand for this receptor is Substance P, although it has some affinity for other tachykinins. The protein is the product of the TACR1 gene.
The adenosine A3 receptor, also known as ADORA3, is an adenosine receptor, but also denotes the human gene encoding it.
Endothelin receptor type B, (ET-B) is a protein that in humans is encoded by the EDNRB gene.
Endothelin receptor type A, also known as ETA, is a human G protein-coupled receptor.
Neuropeptide Y receptor type 2 (Y2R) is a member of the neuropeptide Y receptor family of G-protein coupled receptors, that in humans is encoded by the NPY2R gene.
Tachykinin receptor 3, also known as TACR3, is a protein which in humans is encoded by the TACR3 gene.
Galanin receptor 3 (GAL3) is a G-protein coupled receptor encoded by the GALR3 gene.
Metabotropic glutamate receptor 8 is a protein that in humans is encoded by the GRM8 gene.
Tachykinin-3 is a protein that in humans is encoded by the TAC3 gene.
Preprotachykinin-1,, is a precursor protein that in humans is encoded by the TAC1 gene.
Tachykinin-4 is a protein that in humans is encoded by the TAC4 gene.
GR-159897 is a potent and selective NK2 receptor antagonist drug. It has anxiolytic effects in animal models, and also inhibits bronchoconstriction of the airways, which may potentially make it useful in the treatment of asthma.
L-733,060 is a drug developed by Merck which acts as an orally active, non-peptide, selective antagonist for the NK1 receptor, binding with a Ki of 0.08 nM. Only one enantiomer is active which has made it the subject of several asymmetric synthesis efforts.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.