Certificate of Analysis

ProTx-II-Biotin

Name: ProTx-II-Biotin
Brand: Alomone Labs
SKU: STP-100-B

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

A Blocker of Na_V1.7 and Na_V1.5 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.

Sequence Biotin-YCQKWMWTCDSERKCCEGMVCRLWCKKKLW.

Modifications Disulfide bonds between Cys²-Cys¹⁶, Cys⁹-Cys²¹, and Cys¹⁵-Cys²⁵.

Label Biotin at the N-terminus.

Structure

Activity ProTx-II inhibits Na_V channels¹. ProTx-II could also modulate T-type Ca²⁺ channels at higher concentrations².

References-Activity

Middleton, R.E. et al. (2002) Biochemistry 41, 14734.
Hall, E.O. et al. (2010) FASEB J. 24, 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 Na_V1.7 channels expressed in Xenopus oocytes.
A. Time course of ProTx-II-Biotin (#STP-100-B) inhibition of Na_V1.7 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 Na_V1.7 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.
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).

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 (Na_V) blocker which inhibits both tetrodotoxin-sensitive and tetrodotoxin-resistant channels¹.

Binding of ProTx-II to an extracellular domain of Na_V channel, probably to a hydrophobic site³, inhibits current by shifting the channel activation to more positive potentials^1-2.

ProTx-II Inhibits Na_V1.2, Na_V1.3, Na_V1.5, Na_V1.6, Na_V1.7, and Na_V1.8. It is a significantly more potent inhibitor against Na_V1.7 than the other Na_V channel subtypes¹.

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

Target Na_V Na⁺ channels and T-type Ca²⁺ channels

Peptide Content: 100%

Lyophilized Powder

Last update: 19/10/2022

For research purposes only, not for human use

Specifications

Citations

Applications

Scientific Background

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