Spider toxin

Spider toxin

Solution structure of omega-agatoxin-Aa4a from Agelenopsis aperta.[1]
Identifiers
Symbol Toxin_9
Pfam PF02819
Pfam clan CL0083
InterPro IPR004169
SCOP 1oav
SUPERFAMILY 1oav
OPM superfamily 120
OPM protein 1agg
Delta Atracotoxin
Identifiers
Symbol Atracotoxin
Pfam PF05353
InterPro IPR008017
SCOP 1qdp
SUPERFAMILY 1qdp
OPM protein 1vtx
Spider toxin CSTX family
Identifiers
Symbol Toxin_35
Pfam PF10530
InterPro IPR011142
PROSITE PDOC60029
Spider potassium channel inhibitory toxin
Identifiers
Symbol Toxin_12
Pfam PF07740
Pfam clan CL0083
InterPro IPR011696
SCOP 1d1h
SUPERFAMILY 1d1h
OPM protein 1qk6

Spider toxins are a family of proteins produced by spiders which function as neurotoxins. The mechanism of many spider toxins is through blockage of calcium channels.

A remotely related group of atracotoxins operate by opening sodium channels. Delta atracotoxin produces potentially fatal neurotoxic symptoms in primates by slowing the inactivation of voltage-gated sodium channels.[2] The structure of atracotoxin comprises a core beta region containing a triple-stranded a thumb-like extension protruding from the beta region and a C-terminal helix. The beta region contains a cystine knot motif, a feature seen in other neurotoxic polypeptides[2] and other spider toxins, of the CSTX family.

Spider potassium channel inhibitory toxins is another group of spider toxins. A representative of this group is hanatoxin, a 35 amino acid peptide toxin which was isolated from Chilean rose tarantula (Grammostola rosea, syn. G. spatulata) venom. It inhibits the drk1 voltage-gated potassium channel by altering the energetics of gating.[3] See also Huwentoxin-1 IPR013140.

See also

References

  1. ↑ PDB 1IVA; Reily MD, Holub KE, Gray WR, Norris TM, Adams ME (December 1994). "Structure-activity relationships for P-type calcium channel-selective omega-agatoxins". Nat. Struct. Biol. 1 (12): 853–6. doi:10.1038/nsb1294-853. PMID 7773772.
  2. ↑ 2.0 2.1 Mackay JP, King GF, Fletcher JI, Chapman BE, Howden ME (1997). "The structure of versutoxin (delta-atracotoxin-Hv1) provides insights into the binding of site 3 neurotoxins to the voltage-gated sodium channel". Structure 5 (11): 1525–1535. doi:10.1016/S0969-2126(97)00301-8. PMID 9384567.
  3. ↑ Shimada I, Sato K, Takahashi H, Kim JI, Min HJ, Swartz KJ (2000). "Solution structure of hanatoxin1, a gating modifier of voltage-dependent K(+) channels: common surface features of gating modifier toxins". J. Mol. Biol. 297 (3): 771–780. doi:10.1006/jmbi.2000.3609. PMID 10731427.

Further reading

  • Kim JI, Konishi S, Iwai H, Kohno T, Gouda H, Shimada I, Sato K, Arata Y (July 1995). "Three-dimensional solution structure of the calcium channel antagonist omega-agatoxin IVA: consensus molecular folding of calcium channel blockers". J. Mol. Biol. 250 (5): 659–71. doi:10.1006/jmbi.1995.0406. PMID 7623383.

This article incorporates text from the public domain Pfam and InterPro IPR008017