Delta atracotoxins
| Delta atracotoxin Ar1a ( Atrax robustus ) | ||
|---|---|---|
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| Rod model from Robustoxin according to PDB 1QDP | ||
| Mass / length primary structure | 42 amino acids, 4.85 kDa | |
| Identifier | ||
| External IDs | ||
| Occurrence | ||
| Parent taxon | Hexathelidae | |
Delta atracotoxins (ACTX) are toxic peptides produced by some orthognathic spiders in their venom glands . They work in the body of insects and mammals by binding to certain calcium channels in the cell membrane of nerve cells . They are neurotoxins . All Delta-ACTX peptides are 42 amino acids long and show a high degree of homology with one another .
The ACTX family includes the Delta-ACTX-Ar1 (also: Robustoxin) from the funnel-web spider ( Atrax robustus ), Delta-ACTX-Hv1 (also: Versutoxin) from Hadronyche versutus , Magi 4 from Macrothele gigas and Delta-Missulenatoxin-Mb1a by Missulena bradleyi .
Atracotoxins bind to tetrodotoxin- sensitive calcium channels and prevent them from switching from active to inactive. This leads to an inhibition of the diffusion of calcium ions into the presynapse, whereby the triggering of action potentials in motor neurons and neurons of the autonomic nervous system is blocked.
Individual evidence
- ↑ a b c Swiss Institute of Bioinformatics (SIB): PROSITE documentation PDOC60018. ACTX family. Retrieved August 15, 2011 .