ID   CKE_CONER               Reviewed;          96 AA.
AC   P0C8D9;
DT   04-NOV-2008, integrated into UniProtKB/Swiss-Prot.
DT   04-NOV-2008, sequence version 1.
DT   03-AUG-2022, entry version 39.
DE   RecName: Full=Conantokin-E {ECO:0000303|PubMed:18586049};
DE            Short=Con-E {ECO:0000303|PubMed:18586049};
DE   Flags: Precursor; Fragment;
OS   Conus ermineus (Agate cone) (Chelyconus ermineus).
OC   Eukaryota; Metazoa; Spiralia; Lophotrochozoa; Mollusca; Gastropoda;
OC   Caenogastropoda; Neogastropoda; Conoidea; Conidae; Conus; Chelyconus.
OX   NCBI_TaxID=55423;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], DISULFIDE BOND, AND GAMMA-CARBOXYGLUTAMATION AT
RP   GLU-75; GLU-76; GLU-82; GLU-86 AND GLU-95.
RC   TISSUE=Venom duct;
RX   PubMed=18586049; DOI=10.1016/j.toxicon.2008.04.178;
RA   Gowd K.H., Twede V., Watkins M., Krishnan K.S., Teichert R.W., Bulaj G.,
RA   Olivera B.M.;
RT   "Conantokin-P, an unusual conantokin with a long disulfide loop.";
RL   Toxicon 52:203-213(2008).
CC   -!- FUNCTION: Conantokins inhibit N-methyl-D-aspartate (NMDA) receptors.
CC       This toxin has the highest potency for the NR2B/GRIN2B subunit,
CC       followed by NR2A/GRIN2A, NR2C/GRIN2C, and NR2D/GRIN2D subunits.
CC       {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000305|PubMed:18586049}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom duct.
CC       {ECO:0000305|PubMed:18586049}.
CC   -!- DOMAIN: The cysteine framework is C-C. {ECO:0000305}.
CC   -!- MISCELLANEOUS: Adopts an alpha-helical conformation in presence and in
CC       absence of divalent cations. Calcium facilitates disulfide bond
CC       formation of the synthetic peptide. {ECO:0000269|PubMed:18586049}.
CC   -!- SIMILARITY: Belongs to the conotoxin B superfamily. {ECO:0000305}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   AlphaFoldDB; P0C8D9; -.
DR   SMR; P0C8D9; -.
DR   ConoServer; 3533; Conantokin-E1 precursor.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0035792; C:host cell postsynaptic membrane; IEA:UniProtKB-KW.
DR   GO; GO:0099106; F:ion channel regulator activity; IEA:UniProtKB-KW.
DR   GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR   InterPro; IPR005918; Conantokin_CS.
DR   Pfam; PF10550; Toxin_36; 1.
DR   PROSITE; PS60025; CONANTOKIN; 1.
PE   1: Evidence at protein level;
KW   Calcium; Disulfide bond; Gamma-carboxyglutamic acid;
KW   Ion channel impairing toxin; Ionotropic glutamate receptor inhibitor;
KW   Magnesium; Metal-binding; Neurotoxin; Postsynaptic neurotoxin; Secreted;
KW   Signal; Toxin.
FT   SIGNAL          <1..24
FT                   /evidence="ECO:0000255"
FT   PROPEP          25..72
FT                   /evidence="ECO:0000305|PubMed:18586049"
FT                   /id="PRO_0000353125"
FT   PEPTIDE         73..96
FT                   /note="Conantokin-E"
FT                   /evidence="ECO:0000305|PubMed:18586049"
FT                   /id="PRO_0000353126"
FT   REGION          28..57
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   BINDING         82
FT                   /ligand="a divalent metal cation"
FT                   /ligand_id="ChEBI:CHEBI:60240"
FT                   /note="via 4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231"
FT   BINDING         86
FT                   /ligand="a divalent metal cation"
FT                   /ligand_id="ChEBI:CHEBI:60240"
FT                   /note="via 4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231"
FT   MOD_RES         75
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:18586049"
FT   MOD_RES         76
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:18586049"
FT   MOD_RES         82
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:18586049"
FT   MOD_RES         86
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:18586049"
FT   MOD_RES         95
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000305|PubMed:18586049"
FT   DISULFID        83..96
FT                   /evidence="ECO:0000305|PubMed:18586049"
FT   NON_TER         1
SQ   SEQUENCE   96 AA;  10896 MW;  BEC114988156ABDE CRC64;
     LLVPLVTFHL ILGMGTLDHG GALTERRSAD ATALKPEPVL LQKSDARSTD DNDKDRLTQM
     KRILKKRGNK ARGEEEHSKY QECLREIRVN NVQQEC