ID   TX1B_MONBA              Reviewed;          38 AA.
AC   P0DUC2;
DT   02-DEC-2020, integrated into UniProtKB/Swiss-Prot.
DT   02-DEC-2020, sequence version 1.
DT   25-MAY-2022, entry version 6.
DE   RecName: Full=Mu/omega-theraphotoxin-Mb1b {ECO:0000305|PubMed:28475112};
DE            Short=Mu/omega-TRTX-Mb1b {ECO:0000303|PubMed:28475112};
OS   Monocentropus balfouri (Socotra Island blue baboon tarantula).
OC   Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Chelicerata; Arachnida; Araneae;
OC   Mygalomorphae; Theraphosidae; Monocentropus.
OX   NCBI_TaxID=2053173;
RN   [1]
RP   PROTEIN SEQUENCE, FUNCTION, AMIDATION AT SER-38, MASS SPECTROMETRY,
RP   SUBCELLULAR LOCATION, RECOMBINANT EXPRESSION, TOXIC DOSE, AND BIOASSAY.
RC   TISSUE=Venom;
RX   PubMed=28475112; DOI=10.3390/toxins9050155;
RA   Smith J.J., Herzig V., Ikonomopoulou M.P., Dziemborowicz S., Bosmans F.,
RA   Nicholson G.M., King G.F.;
RT   "Insect-active toxins with promiscuous pharmacology from the african
RT   theraphosid spider Monocentropus balfouri.";
RL   Toxins 9:0-0(2017).
CC   -!- FUNCTION: Paralytic toxin on insects that inhibits voltage-gated sodium
CC       (Nav) and calcium (Cav) channels in P.americana (American cockroach)
CC       dorsal unpaired median (DUM) neurons, and also inhibits the B.germanica
CC       (German cockroach) Nav channel (BgNaV1) (PubMed:28475112). May act as a
CC       gating-modifier toxin on Nav and as a pore blocker on Cav
CC       (PubMed:28475112). In vivo, reversibly paralyzes both L.cuprina
CC       (Australian sheep blowfly) and M.domestica (housefly), but does not
CC       affect larvae of H.armigera (cotton bollworms) (PubMed:28475112).
CC       {ECO:0000269|PubMed:28475112}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:28475112}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC       {ECO:0000305|PubMed:28475112}.
CC   -!- DOMAIN: The presence of a 'disulfide through disulfide knot'
CC       structurally defines this protein as a knottin.
CC       {ECO:0000250|UniProtKB:P0DM12}.
CC   -!- MASS SPECTROMETRY: Mass=4147.00; Method=MALDI;
CC       Evidence={ECO:0000269|PubMed:28475112};
CC   -!- TOXIC DOSE: PD(50) is 5.6+-0.2 nmol/g when intra-thoracically injected
CC       into L.cuprina blowflies (at 30 minutes post-injection).
CC       {ECO:0000269|PubMed:28475112}.
CC   -!- TOXIC DOSE: PD(50) is 6.0+-0.2 nmol/g when intra-thoracically injected
CC       into L.cuprina blowflies (at 1 hour post-injection).
CC       {ECO:0000269|PubMed:28475112}.
CC   -!- TOXIC DOSE: PD(50) is 7.7+-0.5 nmol/g when intra-thoracically injected
CC       into L.cuprina blowflies (at 2 hours post-injection).
CC       {ECO:0000269|PubMed:28475112}.
CC   -!- MISCELLANEOUS: Possibly exists in two forms, due to cis-trans
CC       isomerization of Pro-5 or Pro-22. {ECO:0000269|PubMed:28475112}.
CC   -!- SIMILARITY: Belongs to the neurotoxin 10 (Hwtx-1) family. 28 (Jztx-11)
CC       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   AlphaFoldDB; P0DUC2; -.
DR   SMR; P0DUC2; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0005246; F:calcium channel regulator activity; IEA:UniProtKB-KW.
DR   GO; GO:0008200; F:ion channel inhibitor activity; IEA:InterPro.
DR   GO; GO:0017080; F:sodium channel regulator activity; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR   InterPro; IPR011696; Huwentoxin-1.
DR   Pfam; PF07740; Toxin_12; 1.
PE   1: Evidence at protein level;
KW   Amidation; Calcium channel impairing toxin; Direct protein sequencing;
KW   Disulfide bond; Ion channel impairing toxin; Knottin; Neurotoxin; Secreted;
KW   Toxin; Voltage-gated calcium channel impairing toxin;
KW   Voltage-gated sodium channel impairing toxin.
FT   CHAIN           1..38
FT                   /note="Mu/omega-theraphotoxin-Mb1b"
FT                   /evidence="ECO:0000269|PubMed:28475112"
FT                   /id="PRO_0000451472"
FT   MOD_RES         38
FT                   /note="Serine amide"
FT                   /evidence="ECO:0000269|PubMed:28475112"
FT   DISULFID        7..21
FT                   /evidence="ECO:0000250|UniProtKB:P0DM12"
FT   DISULFID        14..26
FT                   /evidence="ECO:0000250|UniProtKB:P0DM12"
FT   DISULFID        20..33
FT                   /evidence="ECO:0000250|UniProtKB:P0DM12"
SQ   SEQUENCE   38 AA;  4156 MW;  9DA490388BDD258D CRC64;
     GVDKPGCRYM FGGCVQDDDC CPHLGCKRKG LYCAWDAS