Summary: Toxin with inhibitor cystine knot ICK or Knottin scaffold
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Spider toxin Edit Wikipedia article
|Spider toxin CSTX family|
|Spider potassium channel inhibitory toxin|
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. 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 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. See also Huwentoxin-1 InterPro: IPR013140.
- doi:10.1038/nsb1294-853. PMID 7773772.; 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.
- 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.
- 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.
- 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.
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Toxin with inhibitor cystine knot ICK or Knottin scaffold Provide feedback
Spider toxins of the CSTX family are ion channel toxins containing an inhibitor cystine knot (ICK) structural motif or Knottin scaffold. The four disulfide bonds present in the CSTX spider toxin family are arranged in the following pattern: 1-4, 2-5, 3-8 and 6-7. CSTX-1 is the most important component of C. salei venom in terms of relative abundance and toxicity and therefore is likely to contribute significantly to the overall toxicity of the whole venom. CSTX-1 blocked rat neuronal L-type, but no other types of HVA Cav channels . Interestingly, the omega-toxins from Phoneutria nigriventer venom (another South American species also belonging to the Ctenidae family) are included as they carry the same disulfide bond arrangement. suggestive that CSTX-1 may interact with Cav channels. Calcium ion voltage channel heteromultimer containing an L-type pore-forming alpha1-subunit is the most probable candidate for the molecular target of CSTX-1 and these toxins .
Kuhn-Nentwig L, Schaller J, Kampfer U, Imboden H, Malli H, Nentwig W; , Arch Insect Biochem Physiol. 2000;44:101-111.: A lysine rich C-terminal tail is directly involved in the toxicity of CSTX-1, a neurotoxic peptide from the venom of the spider Cupiennius salei. PUBMED:10897091 EPMC:10897091
Schalle J, Kampfer U, Schurch S, Kuhn-Nentwig L, Haeberli S, Nentwig W; , Cell Mol Life Sci. 2001;58:1538-1545.: CSTX-9, a toxic peptide from the spider Cupiennius salei: amino acid sequence, disulphide bridge pattern and comparison with other spider toxins containing the cystine knot structure. PUBMED:11693532 EPMC:11693532
Kubista H, Mafra RA, Chong Y, Nicholson GM, Beirao PS, Cruz JS, Boehm S, Nentwig W, Kuhn-Nentwig L; , Neuropharmacology. 2007;52:1650-1662.: CSTX-1, a toxin from the venom of the hunting spider Cupiennius salei, is a selective blocker of L-type calcium channels in mammalian neurons. PUBMED:17517422 EPMC:17517422
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR019553
Spider toxins of the CSTX family are ion channel toxins containing an inhibitor cystine knot (ICK) structural motif or Knottin scaffold. The four disulphide bonds present in the CSTX spider toxin family are arranged in the following pattern: 1-4, 2-5, 3-8 and 6-7. CSTX-1 is the most important component of Cupiennius salei (Wandering spider) venom in terms of relative abundance and toxicity and therefore is likely to contribute significantly to the overall toxicity of the whole venom. CSTX-1 blocked rat neuronal L-type, but no other types of HVA Cav channels [PUBMED:17517422]. Interestingly, the omega-toxins from Phoneutria nigriventer (Brazilian armed spider) venom (another South American species also belonging to the Ctenidae family) are included as they carry the same disulphide bond arrangement. suggested that CSTX-1 may interact with Cav channels. Calcium ion voltage channel heteromultimer containing an L-type pore-forming alpha1-subunit is the most probable candidate for the molecular target of CSTX-1 these toxins [PUBMED:17517422].
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
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This clan contains a set of related small protein toxins and what appears to be the functionally distinct Albumin I domain. All members of this clan have a knottin-like fold. Additional information about this clan may be found from .
The clan contains the following 34 members:ACI44 Agouti Albumin_I Albumin_I_a Antifungal_pept Antimicrobial25 Argos Atracotoxin CART CBM_1 Chi-conotoxin Conotoxin LEAP-2 Mu-conotoxin Omega-toxin Tachystatin_A Tachystatin_B Toxin_11 Toxin_12 Toxin_16 Toxin_18 Toxin_20 Toxin_21 Toxin_22 Toxin_23 Toxin_24 Toxin_27 Toxin_28 Toxin_30 Toxin_35 Toxin_7 Toxin_9 UPF0506 Viral_cys_rich
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.
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|Previous IDs:||Toxin_35; Toxin35_;|
|Author:||Finn R, Coggill P|
|Number in seed:||9|
|Number in full:||0|
|Average length of the domain:||0.00 aa|
|Average identity of full alignment:||0 %|
|Average coverage of the sequence by the domain:||0.00 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 26740544 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||8|
|Download:||download the raw HMM for this family|
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How the sunburst is generated
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Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
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Since we reduce the species tree to only the eight main taxonomic levels, sequences that are mapped to the sub-species level in the tree would not normally be shown. Rather than leave out these species, we map them instead to their parent species. So, for example, for sequences belonging to one of the Vibrio cholerae sub-species in the NCBI taxonomy, we show them instead as belonging to the species Vibrio cholerae.
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The tree shows the occurrence of this domain across different species. More...
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For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
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We use the NCBI species tree to group organisms according to their taxonomy and this forms the structure of the displayed tree. Note that in some cases the trees are too large (have too many nodes) to allow us to build an interactive tree, but in most cases you can still view the tree in a plain text, non-interactive representation. Those species which are represented in the seed alignment for this domain are highlighted.
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