Paspalinine
(right click,save link as to download,it is a temp file,please download as soon as possible, you can also use CTRL+S to save the whole html page)
Basic Info
| Common Name | Paspalinine(F04993) |
| 2D Structure | |
| Description | Paspalinine is a tremorgenic mycotoxin that has been found in fungi of the genera Penicillium and Aspergillus. It may be found in contaminated cereal crops such as oats, barley, millet, corn |
| FRCD ID | F04993 |
| CAS Number | 63722-91-8 |
| PubChem CID | 114727 |
| Formula | C27H31NO4 |
| IUPAC Name | None |
| InChI Key | BPTIXFRJAOKMRK-UHFFFAOYSA-N |
| InChI | InChI=1S/C27H31NO4/c1-23(2)22-19(29)14-20-26(30)10-9-15-13-17-16-7-5-6-8-18(16)28-21(17)25(15,4)24(26,3)11-12-27(20,31-22)32-23/h5-8,14-15,22,28,30H,9-13H2,1-4H3 |
| Canonical SMILES | CC1(C2C(=O)C=C3C4(CCC5CC6=C(C5(C4(CCC3(O2)O1)C)C)NC7=CC=CC=C67)O)C |
| Isomeric SMILES | CC1(C2C(=O)C=C3C4(CCC5CC6=C(C5(C4(CCC3(O2)O1)C)C)NC7=CC=CC=C67)O)C |
| Synonyms |
AC1L3FUT
AC1Q6C1D
5b-hydroxy-2,2,13b,13c-tetramethyl-2,3,5b,6,7,7a,8,13,13b,13c,14,15-dodecahydro-4h-3,15a-epoxy[1]benzoxepino[6',7':6,7]indeno[1,2-b]indol-4-one
|
| Classifies |
Fungal Toxin
|
| Update Date | Nov 13, 2018 17:07 |
Chemical Taxonomy
| Kingdom | Organic compounds |
| Superclass | Organoheterocyclic compounds |
| Class | Naphthopyrans |
| Subclass | Not available |
| Intermediate Tree Nodes | Not available |
| Direct Parent | Naphthopyrans |
| Alternative Parents | |
| Molecular Framework | Aromatic heteropolycyclic compounds |
| Substituents | Naphthopyran - Naphthalene - 3-alkylindole - Indole - Indole or derivatives - Dihydropyranone - Ketal - Pyran - Benzenoid - Heteroaromatic compound - Tertiary alcohol - Pyrrole - Meta-dioxolane - Cyclic alcohol - Ketone - Acetal - Oxacycle - Azacycle - Organooxygen compound - Organic oxide - Organopnictogen compound - Organic oxygen compound - Organic nitrogen compound - Hydrocarbon derivative - Carbonyl group - Alcohol - Organonitrogen compound - Aromatic heteropolycyclic compound |
| Description | This 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 Name | Property Value |
|---|---|
| Molecular Weight | 433.548 |
| Hydrogen Bond Donor Count | 2 |
| Hydrogen Bond Acceptor Count | 4 |
| Rotatable Bond Count | 0 |
| Complexity | 929 |
| Monoisotopic Mass | 433.225 |
| Exact Mass | 433.225 |
| XLogP | 3.2 |
| Formal Charge | 0 |
| Heavy Atom Count | 32 |
| Defined Atom Stereocenter Count | 0 |
| Undefined Atom Stereocenter Count | 6 |
| Defined Bond Stereocenter Count | 0 |
| Undefined Bond Stereocenter Count | 0 |
| Isotope Atom Count | 0 |
| Covalently-Bonded Unit Count | 1 |
ADMET
| Model | Result | Probability |
|---|---|---|
| Absorption | ||
| Blood-Brain Barrier | BBB+ | 0.8332 |
| Human Intestinal Absorption | HIA+ | 0.9927 |
| Caco-2 Permeability | Caco2- | 0.5292 |
| P-glycoprotein Substrate | Substrate | 0.8357 |
| P-glycoprotein Inhibitor | Non-inhibitor | 0.7172 |
| Non-inhibitor | 0.9315 | |
| Renal Organic Cation Transporter | Non-inhibitor | 0.8326 |
| Distribution | ||
| Subcellular localization | Mitochondria | 0.5130 |
| Metabolism | ||
| CYP450 2C9 Substrate | Non-substrate | 0.8523 |
| CYP450 2D6 Substrate | Non-substrate | 0.8152 |
| CYP450 3A4 Substrate | Substrate | 0.7504 |
| CYP450 1A2 Inhibitor | Inhibitor | 0.8027 |
| CYP450 2C9 Inhibitor | Non-inhibitor | 0.8740 |
| CYP450 2D6 Inhibitor | Non-inhibitor | 0.9256 |
| CYP450 2C19 Inhibitor | Non-inhibitor | 0.8786 |
| CYP450 3A4 Inhibitor | Non-inhibitor | 0.8437 |
| CYP Inhibitory Promiscuity | Low CYP Inhibitory Promiscuity | 0.7642 |
| Excretion | ||
| Toxicity | ||
| Human Ether-a-go-go-Related Gene Inhibition | Weak inhibitor | 0.9907 |
| Non-inhibitor | 0.8766 | |
| AMES Toxicity | Non AMES toxic | 0.6085 |
| Carcinogens | Non-carcinogens | 0.9687 |
| Fish Toxicity | High FHMT | 0.9975 |
| Tetrahymena Pyriformis Toxicity | High TPT | 0.9957 |
| Honey Bee Toxicity | High HBT | 0.6605 |
| Biodegradation | Not ready biodegradable | 0.9876 |
| Acute Oral Toxicity | III | 0.5451 |
| Carcinogenicity (Three-class) | Non-required | 0.4686 |
| Model | Value | Unit |
|---|---|---|
| Absorption | ||
| Aqueous solubility | -4.5666 | LogS |
| Caco-2 Permeability | 0.9812 | LogPapp, cm/s |
| Distribution | ||
| Metabolism | ||
| Excretion | ||
| Toxicity | ||
| Rat Acute Toxicity | 2.8794 | LD50, mol/kg |
| Fish Toxicity | 0.5938 | pLC50, mg/L |
| Tetrahymena Pyriformis Toxicity | 0.8565 | pIGC50, ug/L |
Targets
- 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:
- Paspalinine inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
- 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:
- 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
- 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. 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:
- Paspalinine inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
- 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:
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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:
- Paspalinine inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
- 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:
- Paspalinine inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
- 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:
- Paspalinine inhibits presynaptic high-conductance Ca+2 activated maxi-K+ channels in the smooth muscle.
References
- 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:
- 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
- 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
- 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
- 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
- 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
- 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 ]