ω-agatoxin IVA
ω-agatoxin IVA is a peptide originally isolated from funnel web-spider venom Agelenopsis aperta. This peptide is a specific blocker of P/Q-type calcium channel (Cav2.1). It has been reported that ω-agatoxin IVA is a potent blocker of voltage-gated calcium channels in insect and vertebrate central neurons. The binding site for ω-agatoxin IVA has been localized in part to the extracellular S3–S4 loop in repeat IV of the α-1A Ca2+ channels, which is proximal to the S4 sensor domain. This is coherent with its functional effect (no pore-blocking activity, but gating modifier by a shift of channel activation towards more depolarized potentials). This makes this toxin a voltage-dependent blocker of P/Q calcium channels.
Peptides & proteins
145017-83-0
ω-aga IVA, omega agatoxin IVA
Mintz I.M.,et al. (1992) P-type calcium channels blocked by the spider toxin omega-Aga-IVA. Nature; Bourinet E, et al. (1999) Splicing of alpha 1A subunit gene generates phenotypic variants of P- and Q-type calcium channels. Nat Neurosci. ; Adams ME.(2004) Agatoxins: ion channel specific toxins from the American funnel web spider, Agelenopsis aperta.Toxicon A; Doering CJ, Zamponi GW. (2003) Molecular pharmacology of high voltage-activated calcium channels.J Bioenerg Biomembr.; Winterfield JR, Swartz KJ. (2000) A hot spot for the interaction of gating modifier toxins with voltage-dependent ion channels. J Gen Physiol.; King GF. (2007) Modulation of insect Ca(v) channels by peptidic spider toxins. Toxicon.; Wicher D, Penzlin H. (1998) omega-Toxins affect Na+ currents in neurosecretory insect neurons. Receptors Channels.; Wicher D, Penzlin H. (1997) Ca2+ currents in central insect neurons: electrophysiological and pharmacological properties. J Neurophysiol.
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