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Record Information
Version2.0
Creation Date2010-05-10 14:30:53 UTC
Update Date2014-12-24 20:26:29 UTC
Accession NumberT3D3742
Identification
Common NameFumitremorgin A
ClassSmall Molecule
DescriptionFumitremorgin A (FTA) is a potent neurotropic and tremorgenic mycotoxin isolated from Aspergillus fumigatus. Tremorgenic mycotoxins affect the central nervous system causing sustained tremors, convulsions, and death and have been implicated in a number of neurologic diseases of cattle collectively known as "staggers syndromes". FTA also severely affects the autonomic nervous system, likely through abnormal excitation of the central nervous system. (3, 4)
Compound Type
  • Amide
  • Amine
  • Ether
  • Fungal Toxin
  • Mycotoxin
  • Natural Compound
  • Organic Compound
Chemical Structure
Thumb
Synonyms
Synonym
Fumitremorgin a
Chemical FormulaC32H41N3O7
Average Molecular Mass579.684 g/mol
Monoisotopic Mass579.294 g/mol
CAS Registry Number12626-18-5
IUPAC Name23-hydroxy-5-methoxy-12,12-dimethyl-24-[(3-methylbut-2-en-1-yl)oxy]-9-(2-methylprop-1-en-1-yl)-10,11-dioxa-8,15,21-triazahexacyclo[12.10.1.0²,⁷.0⁸,²⁵.0¹⁵,²³.0¹⁷,²¹]pentacosa-1(25),2(7),3,5-tetraene-16,22-dione
Traditional Name23-hydroxy-5-methoxy-12,12-dimethyl-24-[(3-methylbut-2-en-1-yl)oxy]-9-(2-methylprop-1-en-1-yl)-10,11-dioxa-8,15,21-triazahexacyclo[12.10.1.0²,⁷.0⁸,²⁵.0¹⁵,²³.0¹⁷,²¹]pentacosa-1(25),2(7),3,5-tetraene-16,22-dione
SMILESCOC1=CC2=C(C=C1)C1=C3C(CC(C)(C)OOC(C=C(C)C)N23)N2C(=O)C3CCCN3C(=O)C2(O)C1OCC=C(C)C
InChI IdentifierInChI=1S/C32H41N3O7/c1-18(2)12-14-40-28-26-21-11-10-20(39-7)16-23(21)34-25(15-19(3)4)41-42-31(5,6)17-24(27(26)34)35-29(36)22-9-8-13-33(22)30(37)32(28,35)38/h10-12,15-16,22,24-25,28,38H,8-9,13-14,17H2,1-7H3
InChI KeyInChIKey=ACGHJVZDNQZJOV-UHFFFAOYSA-N
Chemical Taxonomy
Description belongs to the class of organic compounds known as beta carbolines. Beta carbolines are compounds containing a 9H-pyrido[3,4-b]indole moiety.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
ClassIndoles and derivatives
Sub ClassPyridoindoles
Direct ParentBeta carbolines
Alternative Parents
Substituents
  • Beta-carboline
  • Alpha-amino acid or derivatives
  • 3-alkylindole
  • Indole
  • Anisole
  • Dioxopiperazine
  • 2,5-dioxopiperazine
  • Alkyl aryl ether
  • N-alkylpiperazine
  • 1,4-diazinane
  • Piperazine
  • Benzenoid
  • Heteroaromatic compound
  • Tertiary carboxylic acid amide
  • Pyrrolidine
  • Pyrrole
  • Carboxamide group
  • Lactam
  • Dialkyl peroxide
  • Azacycle
  • Ether
  • Oxacycle
  • Dialkyl ether
  • Carboxylic acid derivative
  • Alkanolamine
  • Organic nitrogen compound
  • Hydrocarbon derivative
  • Carbonyl group
  • Organic oxide
  • Organopnictogen compound
  • Organonitrogen compound
  • Organooxygen compound
  • Organic oxygen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External DescriptorsNot Available
Biological Properties
StatusDetected and Not Quantified
OriginExogenous
Cellular Locations
  • Membrane
Biofluid LocationsNot Available
Tissue LocationsNot Available
PathwaysNot Available
ApplicationsNot Available
Biological Roles
Chemical RolesNot Available
Physical Properties
StateSolid
AppearanceWhite powder.
Experimental Properties
PropertyValue
Melting PointNot Available
Boiling PointNot Available
SolubilityNot Available
LogPNot Available
Predicted Properties
PropertyValueSource
Water Solubility0.08 g/LALOGPS
logP3.03ALOGPS
logP4.43ChemAxon
logS-3.9ALOGPS
pKa (Strongest Acidic)10.13ChemAxon
pKa (Strongest Basic)-4ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count7ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area102.7 ŲChemAxon
Rotatable Bond Count5ChemAxon
Refractivity156.9 m³·mol⁻¹ChemAxon
Polarizability63.28 ųChemAxon
Number of Rings6ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash KeyView
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-001i-2000190000-1724f0a3765dfb8a58fbJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-030u-9000260000-2251cc421622f07e5a31JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0g4l-9210000000-3b266cf743b5334ee84dJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-004i-1000190000-a040bcbcad4e17925497JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0w2i-2002920000-2f06f5dc72dc54dd6c00JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4i-9006000000-b9a098482bb580b8d698JSpectraViewer
Toxicity Profile
Route of ExposureOral, dermal, inhalation, and parenteral (contaminated drugs). (6)
Mechanism of ToxicityTremorgenic mycotoxins exert their toxic effects by interfering with neurotransmitter release, possibly by causing degeneration of nerve terminals. They are thought to inhibit gamma-aminobutyric acid (GABA) receptors, both pre- and postsynaptic, as well as inhibit transmitter breakdown at the GABA-T receptors. This would initially increase neurotransmitter levels, potentiating the GABA-induced chloride current, then lead to decreased levels of neurotransmitter in the synapse. (1, 2, 3)
MetabolismNot Available
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)No indication of carcinogenicity to humans (not listed by IARC).
Uses/SourcesFumitremorgin A (FTA) is mycotoxin isolated from Aspergillus fumigatus. (4)
Minimum Risk LevelNot Available
Health EffectsTremorgenic mycotoxins affect central nervous system activity. They cause a neurological disease of cattle known as "staggers syndrome". (3)
SymptomsTremorgenic mycotoxins affect central nervous system activity, inducing neurologic symptoms including mental confusion, paralysis, tremors, seizures, and death. They cause a neurological disease of cattle known as "staggers syndrome", which is characterized by muscle tremors and hyperexcitability. Fumitremorgin A exposure has also been shown to cause bradycardia, arrhythmia, and hypertension. (1, 5)
TreatmentTo control severe tremors caused by tremorgenic mycotoxins, methocarbamol should be administered. Generalized seizures may be treated with diazepam followed by methocarbamol or a barbiturate such as pentobarbital sodium. Gastric lavage should be performed and activated charcoal administered to limit further absorption of toxins. (7)
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
HMDB IDNot Available
PubChem Compound ID107713
ChEMBL IDNot Available
ChemSpider IDNot Available
KEGG IDNot Available
UniProt IDNot Available
OMIM ID
ChEBI IDNot Available
BioCyc IDNot Available
CTD IDNot Available
Stitch IDNot Available
PDB IDNot Available
ACToR IDNot Available
Wikipedia LinkNot Available
References
Synthesis ReferenceNot Available
MSDSNot Available
General References
  1. Valdes JJ, Cameron JE, Cole RJ: Aflatrem: a tremorgenic mycotoxin with acute neurotoxic effects. Environ Health Perspect. 1985 Oct;62:459-63. [2867895 ]
  2. Yao Y, Peter AB, Baur R, Sigel E: The tremorigen aflatrem is a positive allosteric modulator of the gamma-aminobutyric acidA receptor channel expressed in Xenopus oocytes. Mol Pharmacol. 1989 Mar;35(3):319-23. [2538710 ]
  3. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
  4. Nishiyama M, Kuga T: Central effects of the neurotropic mycotoxin fumitremorgin A in the rabbit (I). Effects on the spinal cord. Jpn J Pharmacol. 1989 Jun;50(2):167-73. [2770054 ]
  5. Nishiyama M, Kuga T: Pharmacological effects of the tremorgenic mycotoxin fumitremorgin A. Jpn J Pharmacol. 1986 Apr;40(4):481-9. [3735799 ]
  6. Peraica M, Domijan AM: Contamination of food with mycotoxins and human health. Arh Hig Rada Toksikol. 2001 Mar;52(1):23-35. [11370295 ]
  7. Prevention of stroke by antihypertensive drug treatment in older persons with isolated systolic hypertension. Final results of the Systolic Hypertension in the Elderly Program (SHEP). SHEP Cooperative Research Group. JAMA. 1991 Jun 26;265(24):3255-64. [2046107 ]
  8. Schell MM. Tremorgenic mycotoxin intoxication. Veterinary Medicine. 2000.
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available

Targets

General Function:
Succinate-semialdehyde dehydrogenase binding
Specific Function:
Catalyzes the conversion of gamma-aminobutyrate and L-beta-aminoisobutyrate to succinate semialdehyde and methylmalonate semialdehyde, respectively. Can also convert delta-aminovalerate and beta-alanine.
Gene Name:
ABAT
Uniprot ID:
P80404
Molecular Weight:
56438.405 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
Component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the vertebrate brain. Functions also as histamine receptor and mediates cellular responses to histamine. Functions as receptor for diazepines and various anesthetics, such as pentobarbital; these are bound at a separate allosteric effector binding site. Functions as ligand-gated chloride channel (By similarity).
Gene Name:
GABRA1
Uniprot ID:
P14867
Molecular Weight:
51801.395 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRA2
Uniprot ID:
P47869
Molecular Weight:
51325.85 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRA3
Uniprot ID:
P34903
Molecular Weight:
55164.055 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRA4
Uniprot ID:
P48169
Molecular Weight:
61622.645 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Transporter activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRA5
Uniprot ID:
P31644
Molecular Weight:
52145.645 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRA6
Uniprot ID:
Q16445
Molecular Weight:
51023.69 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Ligand-gated ion channel activity
Specific Function:
Component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the vertebrate brain. Functions also as histamine receptor and mediates cellular responses to histamine. Functions as receptor for diazepines and various anesthetics, such as pentobarbital; these are bound at a separate allosteric effector binding site. Functions as ligand-gated chloride channel (By similarity).
Gene Name:
GABRB1
Uniprot ID:
P18505
Molecular Weight:
54234.085 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
Component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the vertebrate brain. Functions also as histamine receptor and mediates cellular responses to histamine. Functions as receptor for diazepines and various anesthetics, such as pentobarbital; these are bound at a separate allosteric effector binding site. Functions as ligand-gated chloride channel.
Gene Name:
GABRB2
Uniprot ID:
P47870
Molecular Weight:
59149.895 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Gaba-gated chloride ion channel activity
Specific Function:
Component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the vertebrate brain. Functions also as histamine receptor and mediates cellular responses to histamine. Functions as receptor for diazepines and various anesthetics, such as pentobarbital; these are bound at a separate allosteric effector binding site. Functions as ligand-gated chloride channel.
Gene Name:
GABRB3
Uniprot ID:
P28472
Molecular Weight:
54115.04 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Gaba-a receptor activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRD
Uniprot ID:
O14764
Molecular Weight:
50707.835 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRE
Uniprot ID:
P78334
Molecular Weight:
57971.175 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRG1
Uniprot ID:
Q8N1C3
Molecular Weight:
53594.49 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
Component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the vertebrate brain. Functions also as histamine receptor and mediates cellular responses to histamine. Functions as receptor for diazepines and various anesthetics, such as pentobarbital; these are bound at a separate allosteric effector binding site. Functions as ligand-gated chloride channel.
Gene Name:
GABRG2
Uniprot ID:
P18507
Molecular Weight:
54161.78 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRG3
Uniprot ID:
Q99928
Molecular Weight:
54288.16 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Gaba-a receptor activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel. In the uterus, the function of the receptor appears to be related to tissue contractility. The binding of this pI subunit with other GABA(A) receptor subunits alters the sensitivity of recombinant receptors to modulatory agents such as pregnanolone.
Gene Name:
GABRP
Uniprot ID:
O00591
Molecular Weight:
50639.735 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Gaba-a receptor activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel. Rho-1 GABA receptor could play a role in retinal neurotransmission.
Gene Name:
GABRR1
Uniprot ID:
P24046
Molecular Weight:
55882.91 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Gaba-a receptor activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel. Rho-2 GABA receptor could play a role in retinal neurotransmission.
Gene Name:
GABRR2
Uniprot ID:
P28476
Molecular Weight:
54150.41 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Gaba-a receptor activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRR3
Uniprot ID:
A8MPY1
Molecular Weight:
54271.1 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
Transmembrane signaling receptor activity
Specific Function:
GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.
Gene Name:
GABRQ
Uniprot ID:
Q9UN88
Molecular Weight:
72020.875 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
G-protein coupled gaba receptor activity
Specific Function:
Component of a heterodimeric G-protein coupled receptor for GABA, formed by GABBR1 and GABBR2. Within the heterodimeric GABA receptor, only GABBR1 seems to bind agonists, while GABBR2 mediates coupling to G proteins. Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase. Signaling inhibits adenylate cyclase, stimulates phospholipase A2, activates potassium channels, inactivates voltage-dependent calcium-channels and modulates inositol phospholipid hydrolysis. Calcium is required for high affinity binding to GABA. Plays a critical role in the fine-tuning of inhibitory synaptic transmission. Pre-synaptic GABA receptor inhibits neurotransmitter release by down-regulating high-voltage activated calcium channels, whereas postsynaptic GABA receptor decreases neuronal excitability by activating a prominent inwardly rectifying potassium (Kir) conductance that underlies the late inhibitory postsynaptic potentials. Not only implicated in synaptic inhibition but also in hippocampal long-term potentiation, slow wave sleep, muscle relaxation and antinociception. Activated by (-)-baclofen, cgp27492 and blocked by phaclofen.Isoform 1E may regulate the formation of functional GABBR1/GABBR2 heterodimers by competing for GABBR2 binding. This could explain the observation that certain small molecule ligands exhibit differential affinity for central versus peripheral sites.
Gene Name:
GABBR1
Uniprot ID:
Q9UBS5
Molecular Weight:
108319.4 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]
General Function:
G-protein coupled gaba receptor activity
Specific Function:
Component of a heterodimeric G-protein coupled receptor for GABA, formed by GABBR1 and GABBR2. Within the heterodimeric GABA receptor, only GABBR1 seems to bind agonists, while GABBR2 mediates coupling to G proteins. Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase. Signaling inhibits adenylate cyclase, stimulates phospholipase A2, activates potassium channels, inactivates voltage-dependent calcium-channels and modulates inositol phospholipid hydrolysis. Plays a critical role in the fine-tuning of inhibitory synaptic transmission. Pre-synaptic GABA receptor inhibits neurotransmitter release by down-regulating high-voltage activated calcium channels, whereas postsynaptic GABA receptor decreases neuronal excitability by activating a prominent inwardly rectifying potassium (Kir) conductance that underlies the late inhibitory postsynaptic potentials. Not only implicated in synaptic inhibition but also in hippocampal long-term potentiation, slow wave sleep, muscle relaxation and antinociception.
Gene Name:
GABBR2
Uniprot ID:
O75899
Molecular Weight:
105820.52 Da
References
  1. Selala MI, Daelemans F, Schepens PJ: Fungal tremorgens: the mechanism of action of single nitrogen containing toxins--a hypothesis. Drug Chem Toxicol. 1989 Sep-Dec;12(3-4):237-57. [2698801 ]