ID   TXHM1_HERML             Reviewed;          37 AA.
AC   P85505;
DT   14-OCT-2008, integrated into UniProtKB/Swiss-Prot.
DT   14-OCT-2008, sequence version 1.
DT   25-MAY-2022, entry version 29.
DE   RecName: Full=Mu-thomitoxin-Hme1a {ECO:0000305};
DE            Short=Mu-TMTX-Hme1a {ECO:0000305};
DE   AltName: Full=Neurotoxin Hm-1 {ECO:0000303|PubMed:18606177};
OS   Heriaeus mellotteei (Crab spider) (Heriaeus oblongus).
OC   Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Chelicerata; Arachnida; Araneae;
OC   Araneomorphae; Entelegynae; Dionycha; Thomisidae; Heriaeus.
OX   NCBI_TaxID=504442;
RN   [1]
RP   PROTEIN SEQUENCE, FUNCTION, DISULFIDE BONDS, MASS SPECTROMETRY, AND
RP   AMIDATION AT PHE-37.
RC   TISSUE=Venom;
RX   PubMed=18606177; DOI=10.1016/j.toxicon.2008.05.018;
RA   Billen B., Vassilevski A., Nikolsky A., Tytgat J., Grishin E.;
RT   "Two novel sodium channel inhibitors from Heriaeus melloteei spider venom
RT   differentially interacting with mammalian channel's isoforms.";
RL   Toxicon 52:309-317(2008).
RN   [2]
RP   PROTEIN SEQUENCE, FUNCTION, DISULFIDE BONDS, MASS SPECTROMETRY, AND
RP   AMIDATION AT PHE-37.
RC   TISSUE=Venom;
RX   DOI=10.1134/S1990747809030027;
RA   Nikolsky A., Billen B., Vassilevski A., Filkin S., Tytgat J., Grishin E.;
RT   "Voltage-gated sodium channels are targets for toxins from the venom of the
RT   spider Heriaeus melloteei.";
RL   Biochemistry (Mosc.) Suppl. Series A 3:245-253(2009).
CC   -!- FUNCTION: Blocks the Nav1.2/SCN2A, Nav1.4/SCN4A, and Nav1.6/SCN8A
CC       sodium channels. Reduces the peak amplitude of the sodium current and
CC       negatively shifts the steady-state inactivation process. Does not shift
CC       the threshold potential of activation or the voltage corresponding to
CC       maximal current. Does not change the reversal potential of the sodium
CC       current. May act on site 1 of the receptor.
CC       {ECO:0000269|PubMed:18606177, ECO:0000269|Ref.2}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:18606177}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland. {ECO:0000305}.
CC   -!- DOMAIN: The presence of a 'disulfide through disulfide knot'
CC       structurally defines this protein as a knottin.
CC       {ECO:0000250|UniProtKB:P31328}.
CC   -!- PTM: Contains 3 disulfide bonds.
CC   -!- MASS SPECTROMETRY: Mass=4171.9; Method=MALDI;
CC       Evidence={ECO:0000269|PubMed:18606177};
CC   -!- MISCELLANEOUS: Does not inhibit the sodium channel Nav1.8/SCN10A sodium
CC       channel.
CC   -!- SIMILARITY: Belongs to the neurotoxin 01 (U2-agtx) family.
CC       {ECO:0000305}.
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DR   AlphaFoldDB; P85505; -.
DR   SMR; P85505; -.
DR   ArachnoServer; AS000759; mu-thomitoxin-Hme1a.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0017080; F:sodium channel regulator activity; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
PE   1: Evidence at protein level;
KW   Amidation; Direct protein sequencing; Disulfide bond;
KW   Ion channel impairing toxin; Knottin; Neurotoxin; Secreted; Toxin;
KW   Voltage-gated sodium channel impairing toxin.
FT   PEPTIDE         1..37
FT                   /note="Mu-thomitoxin-Hme1a"
FT                   /id="PRO_0000352650"
FT   MOD_RES         37
FT                   /note="Phenylalanine amide"
FT                   /evidence="ECO:0000269|PubMed:18606177, ECO:0000269|Ref.2"
FT   DISULFID        2..18
FT                   /evidence="ECO:0000250|UniProtKB:P31328"
FT   DISULFID        9..22
FT                   /evidence="ECO:0000250|UniProtKB:P31328"
FT   DISULFID        17..33
FT                   /evidence="ECO:0000250|UniProtKB:P31328"
SQ   SEQUENCE   37 AA;  4179 MW;  762FEED3CA16437F CRC64;
     GCIPYGKTCE FWSGPWCCAG KCKLNVWSMT LSCTRNF