ID   TXMG4_MACGS             Reviewed;         105 AA.
AC   P83560;
DT   27-JUN-2003, integrated into UniProtKB/Swiss-Prot.
DT   22-AUG-2003, sequence version 2.
DT   25-MAY-2022, entry version 85.
DE   RecName: Full=Delta-hexatoxin-Mg1a;
DE            Short=Delta-HXTX-Mg1a;
DE   AltName: Full=Neurotoxin magi-4;
DE   Flags: Precursor;
OS   Macrothele gigas (Japanese funnel web spider).
OC   Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Chelicerata; Arachnida; Araneae;
OC   Mygalomorphae; Macrothelidae; Macrothele.
OX   NCBI_TaxID=223896 {ECO:0000305};
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 63-85, FUNCTION,
RP   SUBCELLULAR LOCATION, TISSUE SPECIFICITY, TOXIC DOSE, AND MASS
RP   SPECTROMETRY.
RC   TISSUE=Venom;
RX   PubMed=12860384; DOI=10.1016/s0014-5793(03)00666-5;
RA   Corzo G., Gilles N., Satake H., Villegas E., Dai L., Nakajima T., Haupt J.;
RT   "Distinct primary structures of the major peptide toxins from the venom of
RT   the spider Macrothele gigas that bind to sites 3 and 4 in the sodium
RT   channel.";
RL   FEBS Lett. 547:43-50(2003).
RN   [2]
RP   STRUCTURE BY NMR OF 63-105, FUNCTION, AND SYNTHESIS OF 63-105.
RX   PubMed=19592486; DOI=10.1074/jbc.m109.030841;
RA   Yamaji N., Little M.J., Nishio H., Billen B., Villegas E., Nishiuchi Y.,
RA   Tytgat J., Nicholson G.M., Corzo G.;
RT   "Synthesis, solution structure, and phylum selectivity of a spider {delta}-
RT   toxin that slows inactivation of specific voltage-gated sodium channel
RT   subtypes.";
RL   J. Biol. Chem. 284:24568-24582(2009).
CC   -!- FUNCTION: Selectively slows channel inactivation of mammalian
CC       Nav1.1/SCN1A, Nav1.3/SCN3A, and Nav1.6/SCN8A and shows higher affinity
CC       for insect Nav1/para channels (site 3). Induces tonic repetitive firing
CC       of nerve impulses in insect neurons accompanied by plateau potentials.
CC       {ECO:0000269|PubMed:12860384, ECO:0000269|PubMed:19592486}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:12860384,
CC       ECO:0000305}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC       {ECO:0000269|PubMed:12860384, ECO:0000305}.
CC   -!- DOMAIN: The presence of a 'disulfide through disulfide knot'
CC       structurally defines this protein as a knottin. {ECO:0000250}.
CC   -!- MASS SPECTROMETRY: Mass=5150.0; Method=MALDI;
CC       Evidence={ECO:0000269|PubMed:12860384};
CC   -!- TOXIC DOSE: LD(50) 0.15 pmol/g by intracranial injection into mice.
CC       {ECO:0000269|PubMed:12860384}.
CC   -!- TOXIC DOSE: LD(50) is 1.2 nmol/kg in lepidopteran larvae.
CC       {ECO:0000269|PubMed:12860384}.
CC   -!- SIMILARITY: Belongs to the neurotoxin 06 (delta-actx) family.
CC       {ECO:0000305}.
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DR   EMBL; AB105149; BAC80149.1; -; mRNA.
DR   PDB; 2ROO; NMR; -; A=63-105.
DR   PDBsum; 2ROO; -.
DR   AlphaFoldDB; P83560; -.
DR   BMRB; P83560; -.
DR   SMR; P83560; -.
DR   TCDB; 8.B.6.2.2; the ca(2+) channel-targeting spider toxin (cst) family.
DR   ArachnoServer; AS000382; delta-hexatoxin-Mg1a.
DR   EvolutionaryTrace; P83560; -.
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   InterPro; IPR008017; Atracotoxin_delta.
DR   Pfam; PF05353; Atracotoxin; 1.
DR   PROSITE; PS60018; DELTA_ACTX; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Cleavage on pair of basic residues;
KW   Direct protein sequencing; Disulfide bond; Ion channel impairing toxin;
KW   Knottin; Neurotoxin; Secreted; Signal; Toxin;
KW   Voltage-gated sodium channel impairing toxin.
FT   SIGNAL          1..18
FT                   /evidence="ECO:0000255"
FT   PROPEP          19..60
FT                   /id="PRO_0000035529"
FT   PEPTIDE         63..105
FT                   /note="Delta-hexatoxin-Mg1a"
FT                   /id="PRO_0000035530"
FT   DISULFID        63..77
FT   DISULFID        70..82
FT   DISULFID        76..93
FT   DISULFID        78..105
FT   STRAND          66..69
FT                   /evidence="ECO:0007829|PDB:2ROO"
FT   HELIX           73..75
FT                   /evidence="ECO:0007829|PDB:2ROO"
FT   STRAND          81..84
FT                   /evidence="ECO:0007829|PDB:2ROO"
FT   HELIX           86..88
FT                   /evidence="ECO:0007829|PDB:2ROO"
FT   STRAND          89..94
FT                   /evidence="ECO:0007829|PDB:2ROO"
FT   STRAND          100..102
FT                   /evidence="ECO:0007829|PDB:2ROO"
SQ   SEQUENCE   105 AA;  12289 MW;  0DDBC59A6102C9A1 CRC64;
     MKTLVIACVA LVLVVVHGEV IEEVNEKQLQ ESVEEKYSLL QRLEKLDEAI TAEENRNSRV
     RRCGSKRAWC KEKKDCCCGY NCVYAWYNQQ SSCERKWKYL FTGEC