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1tt3
From Proteopedia
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| Ligands: | |||||||
| Related: | 1OMG, 1MVJ, 1DW4, 1TTK
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
NMR soulution structure of omega-conotoxin [K10]MVIIA
Overview
Neurotransmitter release from preganglionic parasympathetic neurons is resistant to inhibition by selective antagonists of L-, N-, P/Q-, R-, and T-type calcium channels. In this study, the effects of different omega-conotoxins from genus Conus were investigated on current flow-through cloned voltage-sensitive calcium channels expressed in Xenopus oocytes and nerve-evoked transmitter release from the intact preganglionic cholinergic nerves innervating the rat submandibular ganglia. Our results indicate that omega-conotoxin CVID from Conus catus inhibits a pharmacologically distinct voltage-sensitive calcium channel involved in neurotransmitter release, whereas omega-conotoxin MVIIA had no effect. omega-Conotoxin CVID and MVIIA inhibited depolarization-activated Ba(2+) currents recorded from oocytes expressing N-type but not L- or R-type calcium channels. High affinity inhibition of the CVID-sensitive calcium channel was enhanced when position 10 of the omega-conotoxin was occupied by the smaller residue lysine as found in CVID instead of an arginine as found in MVIIA. Given that relatively small differences in the sequence of the N-type calcium channel alpha(1B) subunit can influence omega-conotoxin access (Feng, Z. P., Hamid, J., Doering, C., Bosey, G. M., Snutch, T. P., and Zamponi, G. W. (2001) J. Biol. Chem. 276, 15728-15735), it is likely that the calcium channel in preganglionic nerve terminals targeted by CVID is a N-type (Ca(v)2.2) calcium channel variant.
About this Structure
1TT3 is a Single protein structure of sequence from [1]. Full crystallographic information is available from OCA.
Reference
Omega-conotoxin CVID inhibits a pharmacologically distinct voltage-sensitive calcium channel associated with transmitter release from preganglionic nerve terminals., Adams DJ, Smith AB, Schroeder CI, Yasuda T, Lewis RJ, J Biol Chem. 2003 Feb 7;278(6):4057-62. Epub 2002 Nov 18. PMID:12441339
Page seeded by OCA on Mon Mar 31 00:00:40 2008
