ID   SCN3_MESMA              Reviewed;          85 AA.
AC   Q9BKJ0; Q6EN21; Q9GZC4;
DT   19-DEC-2001, integrated into UniProtKB/Swiss-Prot.
DT   19-DEC-2001, sequence version 2.
DT   03-AUG-2022, entry version 77.
DE   RecName: Full=Anti-neuroexcitation peptide 3;
DE            Short=BmKANEP3;
DE   AltName: Full=Anti-epilepsy peptide;
DE   AltName: Full=Anti-neuroexcitation peptide III;
DE            Short=ANEPIII;
DE   AltName: Full=Toxin KIM;
DE   Flags: Precursor;
OS   Mesobuthus martensii (Manchurian scorpion) (Buthus martensii).
OC   Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Chelicerata; Arachnida;
OC   Scorpiones; Buthida; Buthoidea; Buthidae; Mesobuthus.
OX   NCBI_TaxID=34649;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   TISSUE=Venom gland;
RA   Zhang J.-H., Hua Z.C., Zhu D.X.;
RT   "Cloning of anti-epilepsy peptide cDNA from scorpion Buthus martensii
RT   Karsch.";
RL   Submitted (JAN-1999) to the EMBL/GenBank/DDBJ databases.
RN   [2]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   TISSUE=Venom gland;
RA   Zhang J.-H., Hua Z.C., Zhu D.X.;
RT   "Cloning of anti-neuroexcitation peptide III (ANEP) cDNA from Scorpion
RT   Buthus martensii Karsch.";
RL   Submitted (MAR-2000) to the EMBL/GenBank/DDBJ databases.
RN   [3]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA].
RA   Zeng X.-C., Peng F., Li W.-X.;
RT   "Nucleotide sequence of scorpion toxin.";
RL   Submitted (JUN-2001) to the EMBL/GenBank/DDBJ databases.
RN   [4]
RP   FUNCTION.
RX   PubMed=11321163; DOI=10.1081/pb-100103371;
RA   Zhang J.-H., Hua Z.C., Xu Z., Zheng W.J., Zhu D.X.;
RT   "Expression of anti-neuroexcitation peptide (ANEP) of scorpion Buthus
RT   martensii Karsch in Escherichia coli.";
RL   Prep. Biochem. Biotechnol. 31:49-57(2001).
CC   -!- FUNCTION: Binds to sodium channels (Nav) and inhibits them (By
CC       similarity). Recombinant ANEP delays the convulsion seizure of model
CC       animals by 18% and shows anti-neuroexcitatory activity. {ECO:0000250,
CC       ECO:0000269|PubMed:11321163}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC   -!- DOMAIN: Has the structural arrangement of an alpha-helix connected to
CC       antiparallel beta-sheets by disulfide bonds (CS-alpha/beta).
CC       {ECO:0000305}.
CC   -!- SIMILARITY: Belongs to the long (4 C-C) scorpion toxin superfamily.
CC       Sodium channel inhibitor family. Beta subfamily. {ECO:0000305}.
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DR   EMBL; AF122003; AAG01571.1; -; mRNA.
DR   EMBL; AF242737; AAK28342.1; -; mRNA.
DR   EMBL; AY040630; AAK94768.1; -; Genomic_DNA.
DR   EMBL; AY040631; AAK94769.1; -; mRNA.
DR   AlphaFoldDB; Q9BKJ0; -.
DR   SMR; Q9BKJ0; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0019871; F:sodium channel inhibitor activity; IEA:InterPro.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR   GO; GO:0006952; P:defense response; IEA:InterPro.
DR   CDD; cd00107; Knot1; 1.
DR   Gene3D; 3.30.30.10; -; 1.
DR   InterPro; IPR044062; LCN-type_CS_alpha_beta_dom.
DR   InterPro; IPR003614; Scorpion_toxin-like.
DR   InterPro; IPR036574; Scorpion_toxin-like_sf.
DR   InterPro; IPR018218; Scorpion_toxinL.
DR   InterPro; IPR002061; Scorpion_toxinL/defensin.
DR   Pfam; PF00537; Toxin_3; 1.
DR   PRINTS; PR00285; SCORPNTOXIN.
DR   SMART; SM00505; Knot1; 1.
DR   SUPFAM; SSF57095; SSF57095; 1.
DR   PROSITE; PS51863; LCN_CSAB; 1.
PE   2: Evidence at transcript level;
KW   Disulfide bond; Ion channel impairing toxin; Neurotoxin; Secreted; Signal;
KW   Toxin; Voltage-gated sodium channel impairing toxin.
FT   SIGNAL          1..21
FT                   /evidence="ECO:0000255"
FT   CHAIN           22..85
FT                   /note="Anti-neuroexcitation peptide 3"
FT                   /id="PRO_0000035265"
FT   DOMAIN          22..82
FT                   /note="LCN-type CS-alpha/beta"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   DISULFID        31..81
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   DISULFID        35..56
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   DISULFID        42..63
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   DISULFID        46..65
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   CONFLICT        47
FT                   /note="K -> I (in Ref. 2; AAK28342)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   85 AA;  9271 MW;  C1D6C93A2F82F8C2 CRC64;
     MKLSLLLVIS ASMLIDGLVN ADGYIRGSNG CKISCLWGNE GCNKECKGFG AYYGYCWTWG
     LACWCEGLPD DKTWKSESNT CGGKK