SIXA_MESMA
ID SIXA_MESMA Reviewed; 85 AA.
AC Q9XY87;
DT 07-DEC-2004, integrated into UniProtKB/Swiss-Prot.
DT 01-NOV-1999, sequence version 1.
DT 03-AUG-2022, entry version 76.
DE RecName: Full=Beta-insect depressant toxin BmKITa;
DE Short=BmK ITa;
DE AltName: Full=BmK dITAP3;
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], PROTEIN SEQUENCE OF 22-54, AMIDATION AT GLY-82,
RP ELECTROPHYSIOLOGICAL CHARACTERIZATION, AND MASS SPECTROMETRY.
RC TISSUE=Venom, and Venom gland;
RX PubMed=12472844; DOI=10.1034/j.1399-3011.2003.21020.x;
RA Wang C.-G., Ling M.-H., Chi C.-W., Wang D.-C., Pelhate M.;
RT "Purification of two depressant insect neurotoxins and their gene cloning
RT from the scorpion Buthus martensi Karsch.";
RL J. Pept. Res. 61:7-16(2003).
RN [2]
RP NUCLEOTIDE SEQUENCE [MRNA] OF 22-85, PROTEIN SEQUENCE OF 22-36, MASS
RP SPECTROMETRY, AND FUNCTION.
RC TISSUE=Venom, and Venom gland;
RX PubMed=11566364; DOI=10.1016/s0167-4838(01)00241-2;
RA Guan R.-J., Wang C.-G., Wang M., Wang D.-C.;
RT "A depressant insect toxin with a novel analgesic effect from scorpion
RT Buthus martensii Karsch.";
RL Biochim. Biophys. Acta 1549:9-18(2001).
RN [3]
RP X-RAY CRYSTALLOGRAPHY (2.6 ANGSTROMS).
RX PubMed=11526329; DOI=10.1107/s0907444901011210;
RA Guan R.-J., Xiang Y., Wang M., Li G.-P., Wang D.-C.;
RT "Crystallization and preliminary X-ray analysis of a depressant insect
RT toxin from the scorpion Buthus martensii Karsch.";
RL Acta Crystallogr. D 57:1313-1315(2001).
CC -!- FUNCTION: Depressant insect beta-toxins cause a transient contraction
CC paralysis followed by a slow flaccid paralysis. They bind voltage-
CC independently at site-4 of sodium channels (Nav) and shift the voltage
CC of activation toward more negative potentials thereby affecting sodium
CC channel activation and promoting spontaneous and repetitive firing.
CC This toxin also displays an evident analgesic effect but is devoid of
CC any toxicity on mice. {ECO:0000269|PubMed:11566364}.
CC -!- SUBCELLULAR LOCATION: Secreted.
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 -!- MASS SPECTROMETRY: Mass=6732.1; Method=Electrospray;
CC Evidence={ECO:0000269|PubMed:12472844};
CC -!- MASS SPECTROMETRY: Mass=6722.7; Mass_error=10.8; Method=MALDI;
CC Evidence={ECO:0000269|PubMed:11566364};
CC -!- SIMILARITY: Belongs to the long (4 C-C) scorpion toxin superfamily.
CC Sodium channel inhibitor family. Beta subfamily. {ECO:0000305}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; AF064821; AAD31592.1; -; mRNA.
DR AlphaFoldDB; Q9XY87; -.
DR SMR; Q9XY87; -.
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 1: Evidence at protein level;
KW 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..21
FT /evidence="ECO:0000269|PubMed:11566364,
FT ECO:0000269|PubMed:12472844"
FT CHAIN 22..82
FT /note="Beta-insect depressant toxin BmKITa"
FT /id="PRO_0000035205"
FT DOMAIN 22..82
FT /note="LCN-type CS-alpha/beta"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01210"
FT MOD_RES 82
FT /note="Glycine amide"
FT /evidence="ECO:0000269|PubMed:12472844"
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 66
FT /note="Q -> E (in Ref. 2)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 85 AA; 9312 MW; CCE46711BAF21DAC CRC64;
MKLFLLLLIS ASMLIDGLVN ADGYIRGSNG CKVSCLWGNE GCNKECRAYG ASYGYCWTWG
LACWCQGLPD DKTWKSESNT CGGKK
