SCX3_CENSC
ID SCX3_CENSC Reviewed; 87 AA.
AC P01494; Q95WB9; Q95WC0;
DT 21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT 27-MAR-2002, sequence version 2.
DT 03-AUG-2022, entry version 121.
DE RecName: Full=Toxin CsEv3;
DE Short=CsE v3;
DE AltName: Full=Neurotoxin 3;
DE Flags: Precursor;
OS Centruroides sculpturatus (Arizona bark scorpion).
OC Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Chelicerata; Arachnida;
OC Scorpiones; Buthida; Buthoidea; Buthidae; Centruroides.
OX NCBI_TaxID=218467;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC TISSUE=Venom gland;
RX PubMed=11600153; DOI=10.1016/s0041-0101(01)00174-x;
RA Corona M., Valdez-Cruz N.A., Merino E., Zurita M., Possani L.D.;
RT "Genes and peptides from the scorpion Centruroides sculpturatus Ewing, that
RT recognize Na(+)-channels.";
RL Toxicon 39:1893-1898(2001).
RN [2]
RP PROTEIN SEQUENCE OF 20-84, FUNCTION, SUBCELLULAR LOCATION, TISSUE
RP SPECIFICITY, AND TOXIC DOSE.
RC TISSUE=Venom;
RX PubMed=4460885; DOI=10.1016/0003-9861(74)90082-4;
RA Babin D.R., Watt D.D., Goos S.M., Mlejnek R.V.;
RT "Amino acid sequences of neurotoxic protein variants from the venom of
RT Centruroides sculpturatus Ewing.";
RL Arch. Biochem. Biophys. 164:694-706(1974).
RN [3]
RP X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS), SEQUENCE REVISION, AND DISULFIDE
RP BONDS.
RX PubMed=7080025; DOI=10.1016/0041-0101(82)90137-4;
RA Fontecilla-Camps J.-C., Almassy R.J., Suddath F.L., Bugg C.E.;
RT "The three-dimensional structure of scorpion neurotoxins.";
RL Toxicon 20:1-7(1982).
RN [4]
RP X-RAY CRYSTALLOGRAPHY (3.0 ANGSTROMS) OF 20-84.
RX PubMed=6256740; DOI=10.1073/pnas.77.11.6496;
RA Fontecilla-Camps J.-C., Almassy R.J., Suddath F.L., Watt D.D., Bugg C.E.;
RT "Three-dimensional structure of a protein from scorpion venom: a new
RT structural class of neurotoxins.";
RL Proc. Natl. Acad. Sci. U.S.A. 77:6496-6500(1980).
RN [5]
RP X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS) OF 20-84, AND DISULFIDE BONDS.
RX PubMed=6631968; DOI=10.1016/s0022-2836(83)80159-4;
RA Almassy R.J., Fontecilla-Camps J.-C., Suddath F.L., Bugg C.E.;
RT "Structure of variant-3 scorpion neurotoxin from Centruroides sculpturatus
RT Ewing, refined at 1.8 A resolution.";
RL J. Mol. Biol. 170:497-527(1983).
RN [6]
RP X-RAY CRYSTALLOGRAPHY (1.2 ANGSTROMS) OF 20-84.
RX PubMed=1522588; DOI=10.1016/0022-2836(92)90694-f;
RA Zhao B., Carson M., Ealick S.E., Bugg C.E.;
RT "Structure of scorpion toxin variant-3 at 1.2-A resolution.";
RL J. Mol. Biol. 227:239-252(1992).
CC -!- FUNCTION: Beta toxins bind voltage-independently at site-4 of sodium
CC channels (Nav) and shift the voltage of activation toward more negative
CC potentials thereby affecting sodium channel activation and promoting
CC spontaneous and repetitive firing (By similarity). Induces immediate
CC paralysis in crickets after injection, with a total paralysis occurring
CC within 15-30 minutes and lasting for 1-2 hours. Is also lethal to
CC vertebrate (chicks) when injected in very high dosages (more that 100
CC mg/kg). {ECO:0000250, ECO:0000269|PubMed:4460885}.
CC -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:4460885}.
CC -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC {ECO:0000269|PubMed:4460885}.
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 -!- TOXIC DOSE: PD(50) is 255 mg/kg of insects (crickets).
CC {ECO:0000269|PubMed:4460885}.
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; AF338461; AAL23429.1; -; mRNA.
DR EMBL; AF338462; AAL23430.1; -; mRNA.
DR PDB; 2SN3; X-ray; 1.20 A; A=20-84.
DR PDBsum; 2SN3; -.
DR AlphaFoldDB; P01494; -.
DR SMR; P01494; -.
DR EvolutionaryTrace; P01494; -.
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 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 3D-structure; Amidation; Direct protein sequencing; Disulfide bond;
KW Ion channel impairing toxin; Neurotoxin; Secreted; Signal; Toxin;
KW Voltage-gated sodium channel impairing toxin.
FT SIGNAL 1..19
FT /evidence="ECO:0000269|PubMed:4460885"
FT PEPTIDE 20..84
FT /note="Toxin CsEv3"
FT /id="PRO_0000035290"
FT DOMAIN 20..85
FT /note="LCN-type CS-alpha/beta"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT MOD_RES 84
FT /note="Cysteine amide"
FT /evidence="ECO:0000255"
FT DISULFID 31..84
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT DISULFID 35..60
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT DISULFID 44..65
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT DISULFID 48..67
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT VARIANT 6
FT /note="Missing (in CsEv3B*)"
FT VARIANT 26
FT /note="N -> K (in CsEv3A)"
FT VARIANT 29
FT /note="T -> D (in CsEv3A)"
FT VARIANT 35
FT /note="C -> Y (in CsEv3B*)"
FT VARIANT 46
FT /note="K -> T (in CsEv3A)"
FT TURN 27..29
FT /evidence="ECO:0007829|PDB:2SN3"
FT HELIX 42..49
FT /evidence="ECO:0007829|PDB:2SN3"
FT TURN 51..53
FT /evidence="ECO:0007829|PDB:2SN3"
FT STRAND 56..61
FT /evidence="ECO:0007829|PDB:2SN3"
FT STRAND 64..69
FT /evidence="ECO:0007829|PDB:2SN3"
SQ SEQUENCE 87 AA; 9480 MW; 761857AB95031A8E CRC64;
MNSLLMITAC LFLIGTVWAK EGYLVNKSTG CKYGCLKLGE NEGCDKECKA KNQGGSYGYC
YAFACWCEGL PESTPTYPLP NKSCGKK
