{{Short description|Family of toxins produced by spiders}} {{Pfam_box | Symbol = Toxin_9 | Name = Spider toxin | image = 1IVA.pdb.png | width = | caption = Solution structure of omega-agatoxin-Aa4a from ''Agelenopsis aperta''.<ref name="pmid7773772">{{PDB|1IVA}}; {{cite journal |vauthors=Reily MD, Holub KE, Gray WR, Norris TM, Adams ME | title = Structure-activity relationships for P-type calcium channel-selective omega-agatoxins | journal = Nat. Struct. Biol. | volume = 1 | issue = 12 | pages = 853–6 |date=December 1994 | pmid = 7773772 | doi = 10.1038/nsb1294-853 | s2cid = 42176867 }}</ref> | Pfam= PF02819 | Pfam_clan = CL0083 | InterPro= IPR004169 | SMART= | Prosite = | SCOP = 1oav | TCDB = | OPM family= 112 | OPM protein= 1agg | PDB= }} {{Pfam_box | Symbol = Atracotoxin | Name = Delta Atracotoxin | image = | width = | caption = | Pfam= PF05353 | InterPro= IPR008017 | SMART= | Prosite = | SCOP = 1qdp | TCDB = | OPM family= | OPM protein= 1vtx | PDB= }} {{Pfam_box | Symbol = Toxin_35 | Name = Spider toxin CSTX family | image = | width = | caption = | Pfam= PF10530 | InterPro= IPR011142 | SMART= | PROSITE = PDOC60029 | SCOP = | TCDB = | OPM family= | OPM protein= | PDB= }} {{Pfam_box | Symbol = Toxin_12 | Name = Spider potassium channel inhibitory toxin | image = | width = | caption = | Pfam= PF07740 | Pfam_clan = CL0083 | InterPro= IPR011696 | SMART= | Prosite = | SCOP = 1d1h | TCDB = | OPM family= 112 | OPM protein= 1qk6 | PDB= }} '''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 from the venom of the Sydney funnel-web spider produces potentially fatal neurotoxic symptoms in primates by slowing the inactivation of voltage-gated sodium channels.<ref name="PUB00010496">{{cite journal |vauthors=Mackay JP, King GF, Fletcher JI, Chapman BE, Howden ME |title=The structure of versutoxin (delta-atracotoxin-Hv1) provides insights into the binding of site 3 neurotoxins to the voltage-gated sodium channel |journal=Structure |volume=5 |issue=11 |pages=1525–1535 |year=1997 |pmid=9384567 |doi=10.1016/S0969-2126(97)00301-8|doi-access=free }}</ref> 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<ref name="PUB00010496" /> 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.<ref name="PUB00015236">{{cite journal |vauthors=Shimada I, Sato K, Takahashi H, Kim JI, Min HJ, Swartz KJ |title=Solution structure of hanatoxin1, a gating modifier of voltage-dependent K(+) channels: common surface features of gating modifier toxins |journal=J. Mol. Biol. |volume=297 |issue=3 |pages=771–780 |year=2000 |pmid=10731427 |doi=10.1006/jmbi.2000.3609}}</ref> See also Huwentoxin-1.<ref>{{InterPro|IPR013140}}</ref>
==See also== * Raventoxin
==References== {{reflist}}
==Further reading== {{refbegin}} * {{cite journal |vauthors=Kim JI, Konishi S, Iwai H, Kohno T, Gouda H, Shimada I, Sato K, Arata Y | title = Three-dimensional solution structure of the calcium channel antagonist omega-agatoxin IVA: consensus molecular folding of calcium channel blockers | journal = J. Mol. Biol. | volume = 250 | issue = 5 | pages = 659–71 |date=July 1995 | pmid = 7623383 | doi = 10.1006/jmbi.1995.0406 }} {{refend}}
{{InterPro content|IPR008017}}
{{DEFAULTSORT:Spider Toxin}} Category:Protein domains * Category:Peripheral membrane proteins