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β/ω-theraphotoxin-Tp2a-Biotin, Protoxin-2-Biotin, PT-II-Biotin, ProTx2-Biotin, Protoxin2-Biotin

A Blocker of NaV1.7 and NaV1.5 Channels and some T-Type Ca2+ Channels Conjugated to Biotin

Cat #: STP-100-B
Alternative Name β/ω-theraphotoxin-Tp2a-Biotin, Protoxin-2-Biotin, PT-II-Biotin, ProTx2-Biotin, Protoxin2-Biotin
Lyophilized Powder yes
  • Bioassay Tested
  • Origin Synthetic peptide
    MW: 4053 Da
    Purity: >98% (HPLC)
    Form Lyophilized Powder.
    Effective concentration 10-500 nM.
    Modifications Disulfide bonds between Cys2-Cys16, Cys9-Cys21, and Cys15-Cys25.
    Label Biotin at the N-terminus.
    Activity ProTx-II inhibits NaV channels1. ProTx-II could also modulate T-type Ca2+ channels at higher concentrations2.
    1. Middleton, R.E. et al. (2002) Biochemistry 41, 14734.
    2. Hall, E.O. et al. (2010) FASEB J24, 608.14.
    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 (1000 X g 5 min).
    Storage of solutions Up to one week at 4°C or three months at -20°C.
    Our bioassay
    • Alomone Labs ProTx-II-Biotin inhibits NaV1.7 channels expressed in Xenopus oocytes.
      Alomone Labs ProTx-II-Biotin inhibits NaV1.7 channels expressed in Xenopus oocytes.
      A. Time course of ProTx-II-Biotin (#STP-100-B) inhibition of NaV1.7 channels current. Membrane potential was held at -100 mV, current was elicited by a 100 ms voltage step to 0 mV every 10 sec, and was significantly inhibited by 200 nM ProTx-II-Biotin (bar), applied for 4.5 min. B. Superimposed traces of NaV1.7 current upon application of control and of 200 nM ProTx-II-Biotin (as indicated), taken from the recording shown in A.
    • Alomone Labs ProTx-II-Biotin specifically binds avidin.
      Alomone Labs ProTx-II-Biotin specifically binds avidin.
      SDS-PAGE resolved purified ProTx-II-Biotin (#STP-100-B) specifically binds peroxidase-conjugated avidin, showing a dose-dependent ECL signal at ~4 kDa, absent for the same amount of unlabeled ProTx-II (#STP-100).
    References - Scientific background
    1. Middleton, R.E. et al. (2002) Biochemistry 41, 14734.
    2. Smith, J.J. et al. (2005) J. Biol. Chem280, 11127.
    3. Smith, J.J. et al. (2007) J. Biol. Chem. 282, 12687.
    Scientific background

    ProTx-II is a peptidyl toxin originally produced in Thrixopelma pruriens, the Peruvian green velvet tarantula. It was identified as a voltage-gated Na+ channel (NaV) blocker which inhibits both tetrodotoxin-sensitive and tetrodotoxin-resistant channels1.

    Binding of ProTx-II to an extracellular domain of NaV channel, probably to a hydrophobic site3, inhibits current by shifting the channel activation to more positive potentials1-2.

    ProTx-II Inhibits NaV1.2, NaV1.3, NaV1.5, NaV1.6, NaV1.7, and NaV1.8. It is a significantly more potent inhibitor against NaV1.7 than the other NaV channel subtypes1.

    ProTx-II was also found as an effective modulator which shifts the voltage dependence activity of T-type Ca2+channel1.

    Target NaV Na+ channels and T-type Ca2+ channels
    Peptide Content: 100%
    Last update: 19/10/2022

    ProTx-II-Biotin (#STP-100-B) is a highly pure, synthetic, and biologically active conjugated peptide toxin.

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    For research purposes only, not for human use
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