Basic Info

Common NamePaxilline(F05019)
2D Structure
Description

Tremorgenic agent from Penicillium paxilli, Acremonium lorii, Emericella foveolata, Emericella desertorum and Emericella striata Paxilline is a potassium channel blocker. Paxilline is a toxic, tremorgenic indole alkaloid produced by Penicillium paxilli.

Paxilline belongs to the family of Diterpenes. These are terpene compounds formed by four isoprene units.

FRCD IDF05019
CAS Number57186-25-1
PubChem CID4697
FormulaC27H33NO4
IUPAC Name

None

InChI Key

ACNHBCIZLNNLRS-UHFFFAOYSA-N

InChI

InChI=1S/C27H33NO4/c1-24(2,30)23-20(29)14-18-21(32-23)10-11-25(3)26(4)15(9-12-27(18,25)31)13-17-16-7-5-6-8-19(16)28-22(17)26/h5-8,14-15,21,23,28,30-31H,9-13H2,1-4H3

Canonical SMILES

CC12CCC3C(=CC(=O)C(O3)C(C)(C)O)C1(CCC4C2(C5=C(C4)C6=CC=CC=C6N5)C)O

Isomeric SMILES

CC12CCC3C(=CC(=O)C(O3)C(C)(C)O)C1(CCC4C2(C5=C(C4)C6=CC=CC=C6N5)C)O

WikipediaPaxilline
Synonyms
        
            NCGC00168476-01
        
            CAS_57186-25-1
        
            4b-Hydroxy-2-(1-hydroxy-1-methylethyl)-12b,12c-dimethyl-5,6,6a,7,12,12b,12c,13,14,14a-decahydro-2H-chromeno[5',6':6,7]indeno[1,2-b]indol-3(4bH)-one
        
            paxillin
        
            D0V4WT
        
            AC1L1IR1
        
            GTPL2309
        
            BDBM86263
        
            CTK7H1286
        
            ACNHBCIZLNNLRS-UHFFFAOYSA-N
        
Classifies
                

                  
                    Fungal Toxin
                  

                
        
Update DateNov 13, 2018 17:07

Chemical Taxonomy

KingdomOrganic compounds
SuperclassOrganoheterocyclic compounds
ClassNaphthopyrans
SubclassNot available
Intermediate Tree NodesNot available
Direct ParentNaphthopyrans
Alternative Parents
Molecular FrameworkAromatic heteropolycyclic compounds
SubstituentsNaphthopyran - Naphthalene - 3-alkylindole - Indole - Indole or derivatives - Dihydropyranone - Pyran - Benzenoid - Heteroaromatic compound - Tertiary alcohol - Pyrrole - Cyclic alcohol - Cyclic ketone - Ketone - Oxacycle - Azacycle - Dialkyl ether - Ether - Alcohol - Organic oxide - Organopnictogen compound - Organic oxygen compound - Hydrocarbon derivative - Organic nitrogen compound - Organonitrogen compound - Organooxygen compound - Carbonyl group - Aromatic heteropolycyclic compound
DescriptionThis compound belongs to the class of organic compounds known as naphthopyrans. These are compounds containing a pyran ring fused to a naphthalene moiety. Furan is a 6 membered-ring non-aromatic ring with five carbon and one oxygen atoms. Naphthalene is a polycyclic aromatic hydrocarbon made up of two fused benzene rings.

Properties

Property NameProperty Value
Molecular Weight435.564
Hydrogen Bond Donor Count3
Hydrogen Bond Acceptor Count4
Rotatable Bond Count1
Complexity868
Monoisotopic Mass435.241
Exact Mass435.241
XLogP3.5
Formal Charge0
Heavy Atom Count32
Defined Atom Stereocenter Count0
Undefined Atom Stereocenter Count6
Defined Bond Stereocenter Count0
Undefined Bond Stereocenter Count0
Isotope Atom Count0
Covalently-Bonded Unit Count1

ADMET

Model Result Probability
Absorption
Blood-Brain BarrierBBB+0.9039
Human Intestinal AbsorptionHIA+1.0000
Caco-2 PermeabilityCaco2+0.5257
P-glycoprotein SubstrateSubstrate0.8399
P-glycoprotein InhibitorNon-inhibitor0.7194
Non-inhibitor0.8493
Renal Organic Cation TransporterNon-inhibitor0.8287
Distribution
Subcellular localizationMitochondria0.5652
Metabolism
CYP450 2C9 SubstrateNon-substrate0.8642
CYP450 2D6 SubstrateNon-substrate0.7987
CYP450 3A4 SubstrateSubstrate0.7407
CYP450 1A2 InhibitorInhibitor0.9106
CYP450 2C9 InhibitorNon-inhibitor0.9070
CYP450 2D6 InhibitorNon-inhibitor0.9231
CYP450 2C19 InhibitorNon-inhibitor0.9025
CYP450 3A4 InhibitorNon-inhibitor0.8309
CYP Inhibitory PromiscuityLow CYP Inhibitory Promiscuity0.6863
Excretion
Toxicity
Human Ether-a-go-go-Related Gene InhibitionWeak inhibitor0.9780
Non-inhibitor0.8859
AMES ToxicityNon AMES toxic0.6395
CarcinogensNon-carcinogens0.9655
Fish ToxicityHigh FHMT0.9937
Tetrahymena Pyriformis ToxicityHigh TPT0.9971
Honey Bee ToxicityHigh HBT0.6437
BiodegradationNot ready biodegradable0.9889
Acute Oral ToxicityIII0.5447
Carcinogenicity (Three-class)Non-required0.4773

Model Value Unit
Absorption
Aqueous solubility-4.4638LogS
Caco-2 Permeability1.1985LogPapp, cm/s
Distribution
Metabolism
Excretion
Toxicity
Rat Acute Toxicity2.9141LD50, mol/kg
Fish Toxicity0.5654pLC50, mg/L
Tetrahymena Pyriformis Toxicity0.8830pIGC50, ug/L

References

TitleJournalDatePubmed ID
Development and validation of an ultrahigh performance liquid chromatography-high resolution tandem mass spectrometry assay for nine toxic alkaloids from endophyte-infected pasture grasses in horse serum.J Chromatogr A2018 Jul 2729779692
Immunochemical Analysis of Paxilline and Ergot Alkaloid Mycotoxins in Grass Seeds and Plants.J Agric Food Chem2018 Jan 1029237259
Detection of the tremorgenic mycotoxin paxilline and its desoxy analog in ergot of rye and barley: a new class of mycotoxins added to an old problem.Anal Bioanal Chem2017 Aug28674820
Genotoxicity assessment of five tremorgenic mycotoxins (fumitremorgen B, paxilline, penitrem A, verruculogen, and verrucosidin) produced by molds isolated from fermented meats.J Food Prot2003 Nov14627292
Effect of the mycotoxins penitrem, paxilline and lolitrem B on the electromyographic activity of skeletal and gastrointestinal smooth muscle of sheep.Res Vet Sci1997 Mar-Apr9243707
Toxic and antibiotic properties of red thread, Laetisaria fuciformis.Mycopathologia19969066158
Analysis of endophyte toxins: fescue and other grasses toxic to livestock.J Anim Sci1995 Mar7608022

Targets

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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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:
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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:
Potassium channel regulator activity
Specific Function:
Regulatory subunit of the calcium activated potassium KCNMA1 (maxiK) channel. Modulates the calcium sensitivity and gating kinetics of KCNMA1, thereby contributing to KCNMA1 channel diversity. Increases the apparent Ca(2+)/voltage sensitivity of the KCNMA1 channel. It also modifies KCNMA1 channel kinetics and alters its pharmacological properties. It slows down the activation and the deactivation kinetics of the channel. Acts as a negative regulator of smooth muscle contraction by enhancing the calcium sensitivity to KCNMA1. Its presence is also a requirement for internal binding of the KCNMA1 channel opener dehydrosoyasaponin I (DHS-1) triterpene glycoside and for external binding of the agonist hormone 17-beta-estradiol (E2). Increases the binding activity of charybdotoxin (CTX) toxin to KCNMA1 peptide blocker by increasing the CTX association rate and decreasing the dissociation rate.
Gene Name:
KCNMB1
Uniprot ID:
Q16558
Molecular Weight:
21797.27 Da
Mechanism of Action:
Paxilline inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
  1. Knaus HG, McManus OB, Lee SH, Schmalhofer WA, Garcia-Calvo M, Helms LM, Sanchez M, Giangiacomo K, Reuben JP, Smith AB 3rd, et al.: Tremorgenic indole alkaloids potently inhibit smooth muscle high-conductance calcium-activated potassium channels. Biochemistry. 1994 May 17;33(19):5819-28. [7514038 ]
General Function:
Potassium channel regulator activity
Specific Function:
Regulatory subunit of the calcium activated potassium KCNMA1 (maxiK) channel. Modulates the calcium sensitivity and gating kinetics of KCNMA1, thereby contributing to KCNMA1 channel diversity. Alters the functional properties of the current expressed by the KCNMA1 channel. Isoform 2, isoform 3 and isoform 4 partially inactivate the current of KCNBMA. Isoform 4 induces a fast and incomplete inactivation of KCNMA1 channel that is detectable only at large depolarizations. In contrast, isoform 1 does not induce detectable inactivation of KCNMA1. Two or more subunits of KCNMB3 are required to block the KCNMA1 tetramer.
Gene Name:
KCNMB3
Uniprot ID:
Q9NPA1
Molecular Weight:
31603.26 Da
Mechanism of Action:
Paxilline inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
  1. Knaus HG, McManus OB, Lee SH, Schmalhofer WA, Garcia-Calvo M, Helms LM, Sanchez M, Giangiacomo K, Reuben JP, Smith AB 3rd, et al.: Tremorgenic indole alkaloids potently inhibit smooth muscle high-conductance calcium-activated potassium channels. Biochemistry. 1994 May 17;33(19):5819-28. [7514038 ]
General Function:
Potassium channel regulator activity
Specific Function:
Regulatory subunit of the calcium activated potassium KCNMA1 (maxiK) channel. Modulates the calcium sensitivity and gating kinetics of KCNMA1, thereby contributing to KCNMA1 channel diversity. Decreases the gating kinetics and calcium sensitivity of the KCNMA1 channel, but with fast deactivation kinetics. May decrease KCNMA1 channel openings at low calcium concentrations but increases channel openings at high calcium concentrations. Makes KCNMA1 channel resistant to 100 nM charybdotoxin (CTX) toxin concentrations.
Gene Name:
KCNMB4
Uniprot ID:
Q86W47
Molecular Weight:
23948.465 Da
Mechanism of Action:
Paxilline inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
  1. Knaus HG, McManus OB, Lee SH, Schmalhofer WA, Garcia-Calvo M, Helms LM, Sanchez M, Giangiacomo K, Reuben JP, Smith AB 3rd, et al.: Tremorgenic indole alkaloids potently inhibit smooth muscle high-conductance calcium-activated potassium channels. Biochemistry. 1994 May 17;33(19):5819-28. [7514038 ]
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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:
Voltage-gated potassium channel activity
Specific Function:
Potassium channel activated by both membrane depolarization or increase in cytosolic Ca(2+) that mediates export of K(+). It is also activated by the concentration of cytosolic Mg(2+). Its activation dampens the excitatory events that elevate the cytosolic Ca(2+) concentration and/or depolarize the cell membrane. It therefore contributes to repolarization of the membrane potential. Plays a key role in controlling excitability in a number of systems, such as regulation of the contraction of smooth muscle, the tuning of hair cells in the cochlea, regulation of transmitter release, and innate immunity. In smooth muscles, its activation by high level of Ca(2+), caused by ryanodine receptors in the sarcoplasmic reticulum, regulates the membrane potential. In cochlea cells, its number and kinetic properties partly determine the characteristic frequency of each hair cell and thereby helps to establish a tonotopic map. Kinetics of KCNMA1 channels are determined by alternative splicing, phosphorylation status and its combination with modulating beta subunits. Highly sensitive to both iberiotoxin (IbTx) and charybdotoxin (CTX).
Gene Name:
KCNMA1
Uniprot ID:
Q12791
Molecular Weight:
137558.115 Da
Mechanism of Action:
Paxilline inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
  1. Knaus HG, McManus OB, Lee SH, Schmalhofer WA, Garcia-Calvo M, Helms LM, Sanchez M, Giangiacomo K, Reuben JP, Smith AB 3rd, et al.: Tremorgenic indole alkaloids potently inhibit smooth muscle high-conductance calcium-activated potassium channels. Biochemistry. 1994 May 17;33(19):5819-28. [7514038 ]
General Function:
Potassium channel regulator activity
Specific Function:
Regulatory subunit of the calcium activated potassium KCNMA1 (maxiK) channel. Modulates the calcium sensitivity and gating kinetics of KCNMA1, thereby contributing to KCNMA1 channel diversity. Acts as a negative regulator that confers rapid and complete inactivation of KCNMA1 channel complex. May participate in KCNMA1 inactivation in chromaffin cells of the adrenal gland or in hippocampal CA1 neurons.
Gene Name:
KCNMB2
Uniprot ID:
Q9Y691
Molecular Weight:
27129.37 Da
Mechanism of Action:
Paxilline inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
  1. Knaus HG, McManus OB, Lee SH, Schmalhofer WA, Garcia-Calvo M, Helms LM, Sanchez M, Giangiacomo K, Reuben JP, Smith AB 3rd, et al.: Tremorgenic indole alkaloids potently inhibit smooth muscle high-conductance calcium-activated potassium channels. Biochemistry. 1994 May 17;33(19):5819-28. [7514038 ]
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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
Mechanism of Action:
Tremorgenic mycotoxins 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.
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 ]