ID   TX35A_PHONI             Reviewed;          85 AA.
AC   P61229;
DT   10-MAY-2004, integrated into UniProtKB/Swiss-Prot.
DT   10-MAY-2004, sequence version 1.
DT   25-MAY-2022, entry version 43.
DE   RecName: Full=U1-ctenitoxin-Pn1a {ECO:0000305};
DE            Short=U1-CNTX-Pn1a {ECO:0000305};
DE   AltName: Full=Toxin Pn4B {ECO:0000303|PubMed:10758278};
DE   Flags: Precursor;
OS   Phoneutria nigriventer (Brazilian armed spider) (Ctenus nigriventer).
OC   Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Chelicerata; Arachnida; Araneae;
OC   Araneomorphae; Entelegynae; Lycosoidea; Ctenidae; Phoneutria.
OX   NCBI_TaxID=6918;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   TISSUE=Venom gland;
RX   PubMed=10758278; DOI=10.1016/s0041-0101(99)00237-8;
RA   Penaforte C.L., Prado V.F., Prado M.A.M., Romano-Silva M.A.,
RA   Guimaraes P.E.M., De Marco L., Gomez M.V., Kalapothakis E.;
RT   "Molecular cloning of cDNAs encoding insecticidal neurotoxic peptides from
RT   the spider Phoneutria nigriventer.";
RL   Toxicon 38:1443-1449(2000).
CC   -!- FUNCTION: Insecticidal neurotoxin that reversibly inhibits the N-
CC       methyl-D-aspartate (NMDA)-subtype of ionotropic glutamate receptor
CC       (GRIN) and inhibits inactivation of insect sodium channels (Nav). In
CC       vivo, is highly toxic to insects. {ECO:0000250|UniProtKB:P59367}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000250|UniProtKB:P59367}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC       {ECO:0000305|PubMed:10758278}.
CC   -!- DOMAIN: The presence of a 'disulfide through disulfide knot'
CC       structurally defines this protein as a knottin. {ECO:0000305}.
CC   -!- SIMILARITY: Belongs to the neurotoxin 03 (Tx2) family. 05 subfamily.
CC       {ECO:0000305}.
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DR   AlphaFoldDB; P61229; -.
DR   ArachnoServer; AS000282; U1-ctenitoxin-Pn1a.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0035792; C:host cell postsynaptic membrane; IEA:UniProtKB-KW.
DR   GO; GO:0017080; F:sodium channel regulator activity; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
PE   3: Inferred from homology;
KW   Disulfide bond; Ion channel impairing toxin;
KW   Ionotropic glutamate receptor inhibitor; Knottin; Neurotoxin;
KW   Postsynaptic neurotoxin; Secreted; Signal; Toxin;
KW   Voltage-gated sodium channel impairing toxin.
FT   SIGNAL          1..16
FT                   /evidence="ECO:0000255"
FT   PROPEP          17..34
FT                   /evidence="ECO:0000250"
FT                   /id="PRO_0000035511"
FT   CHAIN           35..81
FT                   /note="U1-ctenitoxin-Pn1a"
FT                   /evidence="ECO:0000305|PubMed:10758278"
FT                   /id="PRO_0000035512"
FT   PROPEP          82..85
FT                   /evidence="ECO:0000305"
FT                   /id="PRO_0000035513"
FT   DISULFID        35..49
FT                   /evidence="ECO:0000305"
FT   DISULFID        42..55
FT                   /evidence="ECO:0000305"
FT   DISULFID        46..81
FT                   /evidence="ECO:0000305"
FT   DISULFID        48..65
FT                   /evidence="ECO:0000305"
FT   DISULFID        57..63
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   85 AA;  9462 MW;  8F991D554DFCE723 CRC64;
     MKVAIVFLSL LVLAFASESI EENREEFPVE ESARCGDINA PCQSDCDCCG YSVTCDCYWS
     SSCKCRESLF PLGMALRKAF CQNKI