ID   CKL_CONLY               Reviewed;         101 AA.
AC   P69745;
DT   26-APR-2005, integrated into UniProtKB/Swiss-Prot.
DT   26-APR-2005, sequence version 1.
DT   03-AUG-2022, entry version 48.
DE   RecName: Full=Conantokin-L {ECO:0000303|PubMed:12350383};
DE            Short=Con-L {ECO:0000303|PubMed:12350383};
DE   Flags: Precursor;
OS   Conus lynceus (Lynceus cone).
OC   Eukaryota; Metazoa; Spiralia; Lophotrochozoa; Mollusca; Gastropoda;
OC   Caenogastropoda; Neogastropoda; Conoidea; Conidae; Conus; Phasmoconus.
OX   NCBI_TaxID=289038;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], SYNTHESIS OF 81-99, FUNCTION,
RP   GAMMA-CARBOXYGLUTAMATION AT GLU-83; GLU-84; GLU-91 AND GLU-95, AND
RP   AMIDATION AT ASN-99.
RC   TISSUE=Venom duct;
RX   PubMed=12350383; DOI=10.1016/s0920-1211(02)00101-8;
RA   Jimenez E.C., Donevan S., Walker C., Zhou L.-M., Nielsen J., Cruz L.J.,
RA   Armstrong H., White H.S., Olivera B.M.;
RT   "Conantokin-L, a new NMDA receptor antagonist: determinants for
RT   anticonvulsant potency.";
RL   Epilepsy Res. 51:73-80(2002).
CC   -!- FUNCTION: Conantokins inhibit N-methyl-D-aspartate (NMDA) receptors.
CC       This toxin is far less potent as an anticonvulsant compound than
CC       conantokin-R. It induces sleep-like symptoms in mice.
CC       {ECO:0000269|PubMed:12350383}.
CC   -!- COFACTOR:
CC       Name=Ca(2+); Xref=ChEBI:CHEBI:29108;
CC         Evidence={ECO:0000250|UniProtKB:P58806};
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420;
CC         Evidence={ECO:0000250|UniProtKB:P58806};
CC       Note=Divalent cations stabilize the toxin the in alpha-helix
CC       conformation. {ECO:0000250|UniProtKB:P58806};
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000305|PubMed:12350383}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom duct.
CC       {ECO:0000305|PubMed:12350383}.
CC   -!- MISCELLANEOUS: The mature peptide does not contain cysteine residue.
CC       {ECO:0000305}.
CC   -!- MISCELLANEOUS: Stabilized by divalent cations. Calcium or magnesium.
CC       {ECO:0000250|UniProtKB:P58806}.
CC   -!- SIMILARITY: Belongs to the conotoxin B superfamily. {ECO:0000305}.
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DR   AlphaFoldDB; P69745; -.
DR   SMR; P69745; -.
DR   ConoServer; 1374; Conantokin-L 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   Amidation; Calcium; 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..21
FT                   /evidence="ECO:0000255"
FT   PROPEP          22..80
FT                   /evidence="ECO:0000305|PubMed:12350383"
FT                   /id="PRO_0000035062"
FT   PEPTIDE         81..99
FT                   /note="Conantokin-L"
FT                   /evidence="ECO:0000305|PubMed:12350383"
FT                   /id="PRO_0000035063"
FT   BINDING         91
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         95
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         83
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:12350383"
FT   MOD_RES         84
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:12350383"
FT   MOD_RES         91
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:12350383"
FT   MOD_RES         95
FT                   /note="4-carboxyglutamate"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:12350383"
FT   MOD_RES         99
FT                   /note="Asparagine amide"
FT                   /evidence="ECO:0000250|UniProtKB:P07231,
FT                   ECO:0000305|PubMed:12350383"
SQ   SEQUENCE   101 AA;  11181 MW;  BB9A7F6F10CC9D5F CRC64;
     MQLYTYLYLL VPLVTFHLIL GTGTLDHGGA LTERRSTDAI ALKPEPVLLQ KSSARSTDDN
     GNDRLTQMKR ILKKRGNKAR GEEEVAKMAA ELAREDAVNG K