Conserved Site

Huwentoxin, conserved site-1 (IPR013140)

Short name: Huwentoxin_CS1


The spider venoms often contain many active peptides such as neurotoxins, lectins, inhibitors to enzyme, etc. These peptides are very important for the spider's hunting and defending. During the long history of spider evolution, the peptides evolved into different structures and functions. Despite their different biological functions the following peptides appear to have evolved from the same ancestors and belong to the huwentoxin-1 family [PMID: 14757201]:

  • Ornithoctonus huwena (Chinese bird spider) (Selenocosmia huwena) huwentoxin-I (HWTX-I), a 33 amino acid peptide, which can block the N-type high-voltage activated calcium channels [PMID: 8212049].
  • O. huwena (Chinese bird spider) (Selenocosmia huwena) huwentoxin-IIIa (HWTX-IIIa).
  • O. huwena (Chinese bird spider) (Selenocosmia huwena) huwentoxin-IV (HWTX-IV), a 35 amino acid peptide, which is an inhibitor of tetrodotoxin (TTX) sensitive voltage-gated sodium channel [PMID: 12827284].
  • O. huwena (Chinese bird spider) (Selenocosmia huwena) huwentoxin-V (HWTX-V), a 35 amino acid insecticidal toxin which can reversibly paralyze in insects [PMID: 12893056].
  • O. huwena (Chinese bird spider) (Selenocosmia huwena) huwenlectin-I (SHL-I), a 32 amino acid peptide with haemagglutination activity but almost no neurotoxin activity.
  • Selenocosmia hainana (Chinese bird spider) Hainantoxin-I (HNTX-I), Hainantoxin-III (HNTX-III), Hainantoxin-IV (HNTX-IV) and Hainantoxin-V (HNTX-V) [PMID: 12727268].
  • Brachypelma smithii (Mexican red knee tarantula) Venom protein 5.
  • Grammostola rosea (Chilean rose tarantula) (Grammostola spatulata) voltage sensor toxin 1.

Peptides of the huwentoxin type I family contain 6 cysteine residues involved in three disulphide bonds. The three disulphide bridges have been assigned as C1-C4, C2-C5 and C3-C6. HWTX-I adopts a compact structure consisting of a small triple-stranded antiparallel beta-sheet and five beta-turns.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns