α-Conotoxin EI

An Antagonist of α1/β1/γ/δ nAChR
    Cat #: STC-900
  • Lyophilized Powder
  • Bioassay Tested
  • Origin Synthetic peptide
    MW: 2094 Da.
    Purity: >98% (HPLC)
    Effective concentration 500 nM - 1 µM.
    Sequence RDXCCYHPTCNMSNPQIC.
    Modifications Disulfide bonds between Cys4-Cys10, Cys5-Cys18. Cys18 - C-terminal amidation, X = Hydroxyproline.
      • α-Conotoxin EI
    Molecular formula C83H126N27O27S5.
    CAS No.: 170663-33-9.
    Activity A selective blocker of α1/β1/γ/δ nAChR.
    Shipping and storage Shipped at room temperature. Product as supplied can be stored intact at room temperature for several weeks. For longer periods, it should be stored at -20°C.
    Solubility Any aqueous buffer. Centrifuge all product preparations before use (10000 x g 5 min).
    Storage of solutions Up to two weeks at 4°C or three months at -20°C.
      • α-Conotoxin EI
        Alomone Labs α-Conotoxin EI inhibits α1/β1/γ/δ nAChR channels heterologously expressed in Xenopus oocytes.
        A. Time course of α-Conotoxin EI (#STC-900) action on muscle α1/β1/γ/δ nAChR. Current amplitudes were plotted as a function of time. Membrane potential was held at -80 mV and oocytes were stimulated by exposure to 10 μM acetylcholine and 3 µM PNU-120596 stimulation every 100 seconds. 0.5 µM (for 4.5 min, green) and 1 µM (for 4.5 min, red) α-Conotoxin EI was perfused during the period marked by the bar, as indicated. B. Superimposed traces of muscle nAChR channel current in the absence (black) and presence of 0.5 µM (green) or 1 µM (red) α-Conotoxin EI (taken from the experiment in A).
    References - Scientific background
      • The nicotinic acetylcholine receptors (nAChRs) are a family of ligand-gated ion channels that are widely expressed throughout the central and peripheral nervous systems. The best characterized nAChR is the receptor at the neuromuscular junction, with four different subunits in a pentameric array, (α1)2β1γδ1.

        Small peptide toxins of Conus origin known as the Aα-conotoxins are highly useful tools for exploring ligand nAChR interactions. α-Conotoxins are known to be selective and potent competitive antagonists of nicotinic acetylcholine receptors2.

        α-Conotoxin EI is a 18 amino acid peptidyl toxin, originally isolated from the Conus ermineus (Athlantic fish-hunting cone) venom. In Torpedo nAChRs, α-conotoxin EI selectively binds the agonist site near the α/δ subunit interface. In mammalian nAChRs α-conotoxin EI shows high affinity for both the α/δ and α/γ subunit interfaces (with some preference for the α/δ site)3.

        The unique binding preference of α-conotoxin EI to the α/δ subunit interface makes it a valuable structural template for superposition of various α-conotoxin possessing distinct receptor subtype specificities4.

    Target α1/β1/γ/δ nAChR
    Net Peptide Content: 100%
    Last update: 20/08/2019

    α-Conotoxin EI (#STC-900) is a highly pure, synthetic, and biologically active peptide toxin.

    For research purposes only, not for human use