Skip to main content
NCBI home page
Biophysical Journal logoLink to Biophysical Journal
. 2001 Jul;81(1):79–88. doi: 10.1016/S0006-3495(01)75681-0

Interaction of SNX482 with domains III and IV inhibits activation gating of alpha(1E) (Ca(V)2.3) calcium channels.

E Bourinet 1, S C Stotz 1, R L Spaetgens 1, G Dayanithi 1, J Lemos 1, J Nargeot 1, G W Zamponi 1
PMCID: PMC1301493  PMID: 11423396

Abstract

We have investigated the action of SNX482, a toxin isolated from the venom of the tarantula Hysterocrates gigas, on voltage-dependent calcium channels expressed in tsa-201 cells. Upon application of 200 nM SNX482, R-type alpha(1E) calcium channels underwent rapid and complete inhibition, which was only poorly reversible upon washout. However, upon application of strong membrane depolarizations, rapid and complete recovery from inhibition was obtained. Tail current analysis revealed that SNX482 mediated an approximately 70 mV depolarizing shift in half-activation potential, suggesting that the toxin inhibits alpha(1E) calcium channels by preventing their activation. Experiments involving chimeric channels combining structural features of alpha(1E) and alpha(1C) subunits indicated that the presence of the domain III and IV of alpha(1E) is a prerequisite for a strong gating inhibition. In contrast, L-type alpha(1C) channels underwent incomplete inhibition at saturating concentrations of SNX482 that was paralleled by a small shift in half-activation potential and which could be rapidly reversed, suggesting a less pronounced effect of the toxin on L-type calcium channel gating. We conclude that SNX482 does not exhibit unequivocal specificity for R-type channels, but highly effectively antagonizes their activation.

Full Text

The Full Text of this article is available as a PDF (125.5 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Adams M. E., Mintz I. M., Reily M. D., Thanabal V., Bean B. P. Structure and properties of omega-agatoxin IVB, a new antagonist of P-type calcium channels. Mol Pharmacol. 1993 Oct;44(4):681–688. [PubMed] [Google Scholar]
  2. Bean B. P. Nitrendipine block of cardiac calcium channels: high-affinity binding to the inactivated state. Proc Natl Acad Sci U S A. 1984 Oct;81(20):6388–6392. doi: 10.1073/pnas.81.20.6388. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bech-Hansen N. T., Naylor M. J., Maybaum T. A., Pearce W. G., Koop B., Fishman G. A., Mets M., Musarella M. A., Boycott K. M. Loss-of-function mutations in a calcium-channel alpha1-subunit gene in Xp11.23 cause incomplete X-linked congenital stationary night blindness. Nat Genet. 1998 Jul;19(3):264–267. doi: 10.1038/947. [DOI] [PubMed] [Google Scholar]
  4. Becker S., Prusak-Sochaczewski E., Zamponi G., Beck-Sickinger A. G., Gordon R. D., French R. J. Action of derivatives of mu-conotoxin GIIIA on sodium channels. Single amino acid substitutions in the toxin separately affect association and dissociation rates. Biochemistry. 1992 Sep 8;31(35):8229–8238. doi: 10.1021/bi00150a016. [DOI] [PubMed] [Google Scholar]
  5. Bourinet E., Soong T. W., Sutton K., Slaymaker S., Mathews E., Monteil A., Zamponi G. W., Nargeot J., Snutch T. P. Splicing of alpha 1A subunit gene generates phenotypic variants of P- and Q-type calcium channels. Nat Neurosci. 1999 May;2(5):407–415. doi: 10.1038/8070. [DOI] [PubMed] [Google Scholar]
  6. Cribbs L. L., Lee J. H., Yang J., Satin J., Zhang Y., Daud A., Barclay J., Williamson M. P., Fox M., Rees M. Cloning and characterization of alpha1H from human heart, a member of the T-type Ca2+ channel gene family. Circ Res. 1998 Jul 13;83(1):103–109. doi: 10.1161/01.res.83.1.103. [DOI] [PubMed] [Google Scholar]
  7. Dubel S. J., Starr T. V., Hell J., Ahlijanian M. K., Enyeart J. J., Catterall W. A., Snutch T. P. Molecular cloning of the alpha-1 subunit of an omega-conotoxin-sensitive calcium channel. Proc Natl Acad Sci U S A. 1992 Jun 1;89(11):5058–5062. doi: 10.1073/pnas.89.11.5058. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. French R. J., Prusak-Sochaczewski E., Zamponi G. W., Becker S., Kularatna A. S., Horn R. Interactions between a pore-blocking peptide and the voltage sensor of the sodium channel: an electrostatic approach to channel geometry. Neuron. 1996 Feb;16(2):407–413. doi: 10.1016/s0896-6273(00)80058-6. [DOI] [PubMed] [Google Scholar]
  9. Lee J. H., Daud A. N., Cribbs L. L., Lacerda A. E., Pereverzev A., Klöckner U., Schneider T., Perez-Reyes E. Cloning and expression of a novel member of the low voltage-activated T-type calcium channel family. J Neurosci. 1999 Mar 15;19(6):1912–1921. doi: 10.1523/JNEUROSCI.19-06-01912.1999. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Li-Smerin Y., Swartz K. J. Gating modifier toxins reveal a conserved structural motif in voltage-gated Ca2+ and K+ channels. Proc Natl Acad Sci U S A. 1998 Jul 21;95(15):8585–8589. doi: 10.1073/pnas.95.15.8585. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. McDonough S. I., Lampe R. A., Keith R. A., Bean B. P. Voltage-dependent inhibition of N- and P-type calcium channels by the peptide toxin omega-grammotoxin-SIA. Mol Pharmacol. 1997 Dec;52(6):1095–1104. doi: 10.1124/mol.52.6.1095. [DOI] [PubMed] [Google Scholar]
  12. McDonough S. I., Mintz I. M., Bean B. P. Alteration of P-type calcium channel gating by the spider toxin omega-Aga-IVA. Biophys J. 1997 May;72(5):2117–2128. doi: 10.1016/S0006-3495(97)78854-4. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Mintz I. M., Venema V. J., Swiderek K. M., Lee T. D., Bean B. P., Adams M. E. P-type calcium channels blocked by the spider toxin omega-Aga-IVA. Nature. 1992 Feb 27;355(6363):827–829. doi: 10.1038/355827a0. [DOI] [PubMed] [Google Scholar]
  14. Newcomb R., Szoke B., Palma A., Wang G., Chen X. h., Hopkins W., Cong R., Miller J., Urge L., Tarczy-Hornoch K. Selective peptide antagonist of the class E calcium channel from the venom of the tarantula Hysterocrates gigas. Biochemistry. 1998 Nov 3;37(44):15353–15362. doi: 10.1021/bi981255g. [DOI] [PubMed] [Google Scholar]
  15. Olivera B. M., McIntosh J. M., Cruz L. J., Luque F. A., Gray W. R. Purification and sequence of a presynaptic peptide toxin from Conus geographus venom. Biochemistry. 1984 Oct 23;23(22):5087–5090. doi: 10.1021/bi00317a001. [DOI] [PubMed] [Google Scholar]
  16. Park C. S., Miller C. Interaction of charybdotoxin with permeant ions inside the pore of a K+ channel. Neuron. 1992 Aug;9(2):307–313. doi: 10.1016/0896-6273(92)90169-e. [DOI] [PubMed] [Google Scholar]
  17. Perez-Reyes E., Cribbs L. L., Daud A., Lacerda A. E., Barclay J., Williamson M. P., Fox M., Rees M., Lee J. H. Molecular characterization of a neuronal low-voltage-activated T-type calcium channel. Nature. 1998 Feb 26;391(6670):896–900. doi: 10.1038/36110. [DOI] [PubMed] [Google Scholar]
  18. Sidach S. S., Mintz I. M. Low-affinity blockade of neuronal N-type Ca channels by the spider toxin omega-agatoxin-IVA. J Neurosci. 2000 Oct 1;20(19):7174–7182. doi: 10.1523/JNEUROSCI.20-19-07174.2000. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Soong T. W., Stea A., Hodson C. D., Dubel S. J., Vincent S. R., Snutch T. P. Structure and functional expression of a member of the low voltage-activated calcium channel family. Science. 1993 May 21;260(5111):1133–1136. doi: 10.1126/science.8388125. [DOI] [PubMed] [Google Scholar]
  20. Spaetgens R. L., Zamponi G. W. Multiple structural domains contribute to voltage-dependent inactivation of rat brain alpha(1E) calcium channels. J Biol Chem. 1999 Aug 6;274(32):22428–22436. doi: 10.1074/jbc.274.32.22428. [DOI] [PubMed] [Google Scholar]
  21. Stea A., Dubel S. J., Snutch T. P. alpha 1B N-type calcium channel isoforms with distinct biophysical properties. Ann N Y Acad Sci. 1999 Apr 30;868:118–130. doi: 10.1111/j.1749-6632.1999.tb11282.x. [DOI] [PubMed] [Google Scholar]
  22. Stea A., Tomlinson W. J., Soong T. W., Bourinet E., Dubel S. J., Vincent S. R., Snutch T. P. Localization and functional properties of a rat brain alpha 1A calcium channel reflect similarities to neuronal Q- and P-type channels. Proc Natl Acad Sci U S A. 1994 Oct 25;91(22):10576–10580. doi: 10.1073/pnas.91.22.10576. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Swartz K. J., MacKinnon R. An inhibitor of the Kv2.1 potassium channel isolated from the venom of a Chilean tarantula. Neuron. 1995 Oct;15(4):941–949. doi: 10.1016/0896-6273(95)90184-1. [DOI] [PubMed] [Google Scholar]
  24. Swartz K. J., MacKinnon R. Mapping the receptor site for hanatoxin, a gating modifier of voltage-dependent K+ channels. Neuron. 1997 Apr;18(4):675–682. doi: 10.1016/s0896-6273(00)80307-4. [DOI] [PubMed] [Google Scholar]
  25. Tomlinson W. J., Stea A., Bourinet E., Charnet P., Nargeot J., Snutch T. P. Functional properties of a neuronal class C L-type calcium channel. Neuropharmacology. 1993 Nov;32(11):1117–1126. doi: 10.1016/0028-3908(93)90006-o. [DOI] [PubMed] [Google Scholar]
  26. Tottene A., Volsen S., Pietrobon D. alpha(1E) subunits form the pore of three cerebellar R-type calcium channels with different pharmacological and permeation properties. J Neurosci. 2000 Jan 1;20(1):171–178. doi: 10.1523/JNEUROSCI.20-01-00171.2000. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Wang G., Dayanithi G., Newcomb R., Lemos J. R. An R-type Ca(2+) current in neurohypophysial terminals preferentially regulates oxytocin secretion. J Neurosci. 1999 Nov 1;19(21):9235–9241. doi: 10.1523/JNEUROSCI.19-21-09235.1999. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Williams M. E., Feldman D. H., McCue A. F., Brenner R., Velicelebi G., Ellis S. B., Harpold M. M. Structure and functional expression of alpha 1, alpha 2, and beta subunits of a novel human neuronal calcium channel subtype. Neuron. 1992 Jan;8(1):71–84. doi: 10.1016/0896-6273(92)90109-q. [DOI] [PubMed] [Google Scholar]
  29. Williams M. E., Marubio L. M., Deal C. R., Hans M., Brust P. F., Philipson L. H., Miller R. J., Johnson E. C., Harpold M. M., Ellis S. B. Structure and functional characterization of neuronal alpha 1E calcium channel subtypes. J Biol Chem. 1994 Sep 2;269(35):22347–22357. [PubMed] [Google Scholar]
  30. Winterfield J. R., Swartz K. J. A hot spot for the interaction of gating modifier toxins with voltage-dependent ion channels. J Gen Physiol. 2000 Nov;116(5):637–644. doi: 10.1085/jgp.116.5.637. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Biophysical Journal are provided here courtesy of The Biophysical Society

RESOURCES