ID   SCX4_LEIHE              Reviewed;          65 AA.
AC   P83644;
DT   15-DEC-2003, integrated into UniProtKB/Swiss-Prot.
DT   01-OCT-2003, sequence version 1.
DT   03-AUG-2022, entry version 61.
DE   RecName: Full=Toxin Lqh4;
DE   AltName: Full=Lqh IV;
DE            Short=LqhIV;
DE   AltName: Full=Toxin IV;
OS   Leiurus hebraeus (Deathstalker scorpion) (Leiurus quinquestriatus
OS   hebraeus).
OC   Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Chelicerata; Arachnida;
OC   Scorpiones; Buthida; Buthoidea; Buthidae; Leiurus.
OX   NCBI_TaxID=6884 {ECO:0000305};
RN   [1] {ECO:0000305}
RP   PROTEIN SEQUENCE, FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY, TOXIC
RP   DOSE, MASS SPECTROMETRY, AMIDATION AT ARG-65, CIRCULAR DICHROISM ANALYSIS,
RP   AND 3D-STRUCTURE MODELING.
RC   TISSUE=Venom {ECO:0000305};
RA   Corzo G., Villegas E., Nakajima T.;
RT   "Isolation and structural characterization of a peptide from the venom of
RT   scorpion with toxicity towards invertebrates and vertebrates.";
RL   Protein Pept. Lett. 8:385-393(2001).
RN   [2]
RP   IDENTIFICATION BY MASS SPECTROMETRY.
RX   PubMed=16551474; DOI=10.1016/j.toxicon.2006.01.015;
RA   Nascimento D.G., Rates B., Santos D.M., Verano-Braga T., Barbosa-Silva A.,
RA   Dutra A.A.A., Biondi I., Martin-Eauclaire M.-F., De Lima M.E.,
RA   Pimenta A.M.C.;
RT   "Moving pieces in a taxonomic puzzle: venom 2D-LC/MS and data clustering
RT   analyses to infer phylogenetic relationships in some scorpions from the
RT   Buthidae family (Scorpiones).";
RL   Toxicon 47:628-639(2006).
CC   -!- FUNCTION: Alpha toxins bind voltage-independently at site-3 of sodium
CC       channels (Nav) and inhibit the inactivation of the activated channels,
CC       thereby blocking neuronal transmission (By similarity).
CC       Intracerebroventricular injection into mice induces immediate
CC       convulsions and urination followed by death. Is toxic to insects and
CC       mice. {ECO:0000250, ECO:0000269|Ref.1}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|Ref.1, ECO:0000305}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland. {ECO:0000269|Ref.1,
CC       ECO:0000305}.
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   -!- MASS SPECTROMETRY: Mass=7211.3; Method=MALDI;
CC       Evidence={ECO:0000269|Ref.1};
CC   -!- TOXIC DOSE: LD(50) is 20.3 +/- 3.0 mg/kg to the insect S.litura.
CC       {ECO:0000269|Ref.1}.
CC   -!- SIMILARITY: Belongs to the long (4 C-C) scorpion toxin superfamily.
CC       Sodium channel inhibitor family. Alpha subfamily. {ECO:0000305}.
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DR   AlphaFoldDB; P83644; -.
DR   SMR; P83644; -.
DR   GO; GO:0005576; C:extracellular region; NAS:UniProtKB.
DR   GO; GO:0019871; F:sodium channel inhibitor activity; NAS:UniProtKB.
DR   GO; GO:0090729; F:toxin activity; IDA:UniProtKB.
DR   GO; GO:0006952; P:defense response; IDA:UniProtKB.
DR   GO; GO:0035821; P:modulation of process of another organism; IDA:UniProtKB.
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   1: Evidence at protein level;
KW   Amidation; Direct protein sequencing; Disulfide bond;
KW   Ion channel impairing toxin; Neurotoxin; Secreted; Toxin;
KW   Voltage-gated sodium channel impairing toxin.
FT   CHAIN           1..65
FT                   /note="Toxin Lqh4"
FT                   /id="PRO_0000066785"
FT   DOMAIN          3..65
FT                   /note="LCN-type CS-alpha/beta"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   MOD_RES         65
FT                   /note="Arginine amide"
FT                   /evidence="ECO:0000269|Ref.1"
FT   DISULFID        13..64
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   DISULFID        17..37
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   DISULFID        23..47
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT   DISULFID        27..49
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
SQ   SEQUENCE   65 AA;  7220 MW;  283442461C2B9E40 CRC64;
     GVRDAYIADD KNCVYTCGAN SYCNTECTKN GAESGYCQWF GKYGNACWCI KLPDKVPIRI
     PGKCR