1TT3

NMR soulution structure of omega-conotoxin [K10]MVIIA

Summary for 1TT3

• Entry DOI: 10.2210/pdb1tt3/pdb
• Related: 1DW4 1MVJ 1OMG 1TTK
• Descriptor: Omega-conotoxin MVIIa (1 entity in total)
• Functional Keywords: cysteine knot, four loop frame work, toxin
• Cellular location: Secreted: P05484
• Total number of polymer chains: 1
• Total formula weight: 2622.21

Authors

Adams, D.J.,Smith, A.B.,Schroeder, C.I.,Yasuda, T.,Lewis, R.J. (deposition date: 2004-06-21, release date: 2004-07-06, Last modification date: 2024-11-20)

Primary citation

Adams, D.J.,Smith, A.B.,Schroeder, C.I.,Yasuda, T.,Lewis, R.J.
omega-conotoxin CVID inhibits a pharmacologically distinct voltage-sensitive calcium channel associated with transmitter release from preganglionic nerve terminals
J.Biol.Chem., 278:4057-4062, 2003

PubMed Abstract: 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.

PubMed: 12441339
DOI: 10.1074/jbc.M209969200

Experimental method

SOLUTION NMR