| Structural highlights
Function
[NXL1_NAJKA] The monomeric form binds with high affinity to muscular, Torpedo (muscle-type), and neuronal alpha-7 nicotinic acetylcholine receptors (nAChR). Has no effect on alpha-3/beta-2 nAChR. Causes paralysis by preventing acetylcholine binding to the nAChR. Does not show any blockade of the nicotine-evoked release of dopamine and does not affect ACh release. In mice lung cancer, causes reduction of tumor growth.[1] [2] [3] [4] [5] [6] [7] [8] [9] The homodimeric form binds with low affinity to Torpedo (muscle-type) and alpha-7 nAChRs, whereas it acquires the capacity to block alpha-3/beta-2 nAChRs.[10] [11] [12] [13] [14] [15] [16] [17] [18]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The three-dimensional structure of alpha-cobra-toxin, the "long" neurotoxin from the venom of Naja naja siamensis, has been determined at 2.8-A resolution. Crystals grown as hexagonal needles have space group P6522 with unit cell parameters a = b = 74.59 A, c = 42.89 A; one molecule per asymmetric unit. Phases were determined with a single isomorphous derivative with HgI2 by using the anomalous scattering of the single-site HgI2 molecule to resolve the phase ambiguity. The polypeptide chain folds into three major loops and one tail emerging from a globular head. The protruding long central loop (residues 21-40) is flanked on either side by two shorter loops (residues 4-13 and 44-55); the tail piece (residues 63-71) hangs behind this loop. The molecular conformation is determined by four disulfides in the head and one at the tip of the long loop, by a triple-stranded beta-pleated sheet involving this loop, and by hydrophobic interactions stabilizing the other two loops. The structure of alpha-cobratoxin is compared to that described for the "short" erabutoxin b which shows similar arrangement of structurally and functionally invariant groups.
Three-dimensional structure of the "long" neurotoxin from cobra venom.,Walkinshaw MD, Saenger W, Maelicke A Proc Natl Acad Sci U S A. 1980 May;77(5):2400-4. PMID:6930640[19]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Osipov AV, Kasheverov IE, Makarova YV, Starkov VG, Vorontsova OV, Ziganshin RKh, Andreeva TV, Serebryakova MV, Benoit A, Hogg RC, Bertrand D, Tsetlin VI, Utkin YN. Naturally occurring disulfide-bound dimers of three-fingered toxins: a paradigm for biological activity diversification. J Biol Chem. 2008 May 23;283(21):14571-80. Epub 2008 Apr 1. PMID:18381281 doi:http://dx.doi.org/M802085200
- ↑ Kang S, Maelicke A. Fluorescein isothiocyanate-labeled alpha-cobratoxin. Biochemical characterization and interaction with acetylcholine receptor from Electrophorus electricus. J Biol Chem. 1980 Aug 10;255(15):7326-32. PMID:6771288
- ↑ Martin BM, Chibber BA, Maelicke A. The sites of neurotoxicity in alpha-cobratoxin. J Biol Chem. 1983 Jul 25;258(14):8714-22. PMID:6553056
- ↑ Alkondon M, Albuquerque EX. alpha-Cobratoxin blocks the nicotinic acetylcholine receptor in rat hippocampal neurons. Eur J Pharmacol. 1990 Dec 4;191(3):505-6. PMID:2086254
- ↑ Apel C, Ricny J, Wagner G, Wessler I. alpha-Bungarotoxin, kappa-bungarotoxin, alpha-cobratoxin and erabutoxin-b do not affect [3H]acetylcholine release from the rat isolated left hemidiaphragm. Naunyn Schmiedebergs Arch Pharmacol. 1995 Dec;352(6):646-52. PMID:9053737
- ↑ Servent D, Winckler-Dietrich V, Hu HY, Kessler P, Drevet P, Bertrand D, Menez A. Only snake curaremimetic toxins with a fifth disulfide bond have high affinity for the neuronal alpha7 nicotinic receptor. J Biol Chem. 1997 Sep 26;272(39):24279-86. PMID:9305882
- ↑ Dajas-Bailador F, Costa G, Dajas F, Emmett S. Effects of alpha-erabutoxin, alpha-bungarotoxin, alpha-cobratoxin and fasciculin on the nicotine-evoked release of dopamine in the rat striatum in vivo. Neurochem Int. 1998 Oct;33(4):307-12. PMID:9840221
- ↑ Antil S, Servent D, Menez A. Variability among the sites by which curaremimetic toxins bind to torpedo acetylcholine receptor, as revealed by identification of the functional residues of alpha-cobratoxin. J Biol Chem. 1999 Dec 3;274(49):34851-8. PMID:10574958
- ↑ Grozio A, Paleari L, Catassi A, Servent D, Cilli M, Piccardi F, Paganuzzi M, Cesario A, Granone P, Mourier G, Russo P. Natural agents targeting the alpha7-nicotinic-receptor in NSCLC: a promising prospective in anti-cancer drug development. Int J Cancer. 2008 Apr 15;122(8):1911-5. PMID:18067132 doi:http://dx.doi.org/10.1002/ijc.23298
- ↑ Osipov AV, Kasheverov IE, Makarova YV, Starkov VG, Vorontsova OV, Ziganshin RKh, Andreeva TV, Serebryakova MV, Benoit A, Hogg RC, Bertrand D, Tsetlin VI, Utkin YN. Naturally occurring disulfide-bound dimers of three-fingered toxins: a paradigm for biological activity diversification. J Biol Chem. 2008 May 23;283(21):14571-80. Epub 2008 Apr 1. PMID:18381281 doi:http://dx.doi.org/M802085200
- ↑ Kang S, Maelicke A. Fluorescein isothiocyanate-labeled alpha-cobratoxin. Biochemical characterization and interaction with acetylcholine receptor from Electrophorus electricus. J Biol Chem. 1980 Aug 10;255(15):7326-32. PMID:6771288
- ↑ Martin BM, Chibber BA, Maelicke A. The sites of neurotoxicity in alpha-cobratoxin. J Biol Chem. 1983 Jul 25;258(14):8714-22. PMID:6553056
- ↑ Alkondon M, Albuquerque EX. alpha-Cobratoxin blocks the nicotinic acetylcholine receptor in rat hippocampal neurons. Eur J Pharmacol. 1990 Dec 4;191(3):505-6. PMID:2086254
- ↑ Apel C, Ricny J, Wagner G, Wessler I. alpha-Bungarotoxin, kappa-bungarotoxin, alpha-cobratoxin and erabutoxin-b do not affect [3H]acetylcholine release from the rat isolated left hemidiaphragm. Naunyn Schmiedebergs Arch Pharmacol. 1995 Dec;352(6):646-52. PMID:9053737
- ↑ Servent D, Winckler-Dietrich V, Hu HY, Kessler P, Drevet P, Bertrand D, Menez A. Only snake curaremimetic toxins with a fifth disulfide bond have high affinity for the neuronal alpha7 nicotinic receptor. J Biol Chem. 1997 Sep 26;272(39):24279-86. PMID:9305882
- ↑ Dajas-Bailador F, Costa G, Dajas F, Emmett S. Effects of alpha-erabutoxin, alpha-bungarotoxin, alpha-cobratoxin and fasciculin on the nicotine-evoked release of dopamine in the rat striatum in vivo. Neurochem Int. 1998 Oct;33(4):307-12. PMID:9840221
- ↑ Antil S, Servent D, Menez A. Variability among the sites by which curaremimetic toxins bind to torpedo acetylcholine receptor, as revealed by identification of the functional residues of alpha-cobratoxin. J Biol Chem. 1999 Dec 3;274(49):34851-8. PMID:10574958
- ↑ Grozio A, Paleari L, Catassi A, Servent D, Cilli M, Piccardi F, Paganuzzi M, Cesario A, Granone P, Mourier G, Russo P. Natural agents targeting the alpha7-nicotinic-receptor in NSCLC: a promising prospective in anti-cancer drug development. Int J Cancer. 2008 Apr 15;122(8):1911-5. PMID:18067132 doi:http://dx.doi.org/10.1002/ijc.23298
- ↑ Walkinshaw MD, Saenger W, Maelicke A. Three-dimensional structure of the "long" neurotoxin from cobra venom. Proc Natl Acad Sci U S A. 1980 May;77(5):2400-4. PMID:6930640
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