K+ channel toxin α-KTx 5.4
A Blocker of KCa2 Channels
    Cat #: STT-400
    Alternative Name K+ channel toxin α-KTx 5.4
  • Lyophilized Powder
  • Bioassay Tested
  • Origin Synthetic peptide
    MW: 3458.16 Da.
    Purity: >98% (HPLC)
    Effective concentration 500 pM - 50 nM.
    Modifications Disulfide bonds between Cys3-Cys21, Cys8-Cys26, and Cys12-Cys28. Tyr31 - C terminal amidation.
    • Tamapin
    Molecular formula C146H238N44O41S6
    Activity Tamapin blocks KCa2 channels. Tamapin displays a remarkable selectivity for KCa2.2 versus KCa2.1 channels1.
    1. Pedarzani, P. et al. (2002) J. Biol. Chem277, 46101.
    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 four weeks at 4°C or three months at -20°C.
    Our bioassay
    • Tamapin
      Alomone Labs Tamapin completely inhibits KCa2.2 (SK2) currents heterologously expressed in Xenopus oocytes.
      Current traces recorded at +5 mV. At the indicated time (arrow) 25 nl of 100 mM CaClwas injected into the oocyte in order to activate outward current. 100 nM Tamapin (#STT-400) were perfused for 1 min (green) to completely inhibit the current.
    References - Scientific background
    1. Rodriguez de la Vega, R.C. and Possani, L.D. (2004) Toxicon 43, 865.
    2. Pedarzani, P. et al. (2002) J. Biol. Chem277, 46101.
    Scientific background Tamapin is a 31 amino acid peptidyl toxin, isolated from the venom of the Indian red scorpion, Mesobuthus tamulus, and is classified as α-5.4 scorpion toxin family1 with three disulfide bridges. Native Tamapin blocks KCa2 channels in pyramidal neurons of the hippocampus as well as in cell lines expressing distinct KCa2 channel subunits. Tamapin displays a remarkable selectivity for KCa2.2 (SK2/KCNN2, IC50 = 24 pM) versus KCa2.1 (SK1/KCNN1, approx 1750 fold) and KCa2.3 (SK3/KCNN3) channels2.
    Target KCa2 K+ channels
    Net Peptide Content: 100%
    Last update: 24/02/2020

    Tamapin (#STT-400) is a highly pure, synthetic, and biologically active peptide toxin.

    For research purposes only, not for human use



    Scientific Background


    Product citations
    1. Chubanov, V. et al. (2012) Br. J. Pharmacol. 166, 1357.
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