| Primary Identifier | IPR005918 | Type | Conserved_site |
| Short Name | Conantokin_CS |
| description | The conantokins are a family of neuroactive peptides found in the venoms of fish-hunting cone snails. They possess a relatively high number of residues (4-5) of the non-standard amino acid gamma-carboxyglutamic acid (Gla), which is generated by the post-translational modification of glutamate (Glu) residues. Conantokins are the only naturally produced peptides known to be N-methyl-D-aspartate (NMDA) receptor antagonists and show therapeutic promise in treating conditions associated with NMDA receptor dysfunction. In animal models they have exhibited anticonvulsant and anti-Parkinsonian properties and have provided neuroprotection within therapeutically acceptable times following transient focal brain ischemia [, , , ].Upon binding of Ca2+ to Gla, conantokin undergoes a conformational transition from a distorted curvilinear 3(10) helix to a linear α-helix. The binding of Ca2+ to conantokin leads to the exposure of a hydrophobic region on the opposite face of the helix []. Conantokins share relatively few sequence elements, which include include sequence identity at the first four residues, homologous positioning of the two most C-terminal Gla residues, and an Arg preceding the most C-terminal Gla [].The conantokin family is currently known to include:Conotoxin G from Conus geographus (Geography cone) (Nubecula geographus).Conantokin-L from Conus lynceus (Lynceus cone) [].Conantokin-R from Conus radiatus (Rayed cone) [].Conantokin-T from Conus tulipa (Fish-hunting cone snail) (Tulip cone) [].Conantokin-P from Conus purpurascens (Purple cone) [].Conantokin-Pr3 from Conus parius (Cone snail) [].Conantokin-Br Conus sulcatus (Sulcate cone) []. |
