385 1155 


Blocker of voltage-gated sodium channels and T-type Cav

Protoxin I (ProTx-I; β-theraphotoxin-Tp1a) is a toxin that was originally isolated from the venom of Thrixopelma pruriens (Peruvian green velvet tarantula). This toxin reversibly inhibits the tetrodotoxin (TTX)-resistant channel Nav1.8 (IC50 = 27 nM) and Nav1.2, Nav1.5 and Nav1.7 with IC50 values between 50 and 100 nM. Furthermore, ProTx-I shifts the voltage dependence activity of T-type Cav3.1 channels (IC50= 50 nM) without affecting the voltage dependence of inactivation. Biotin-ProTx-I is a biotin-tagged version of ProTx-I.

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AA sequence: Glu-Cys2-Arg-Tyr-Trp-Leu-Gly-Gly-Cys9-Ser-Ala-Gly-Gln-Thr-Cys15-Cys16-Lys-His-Leu-Val-Cys21-Ser-Arg-Arg-His-Gly-Trp-Cys28-Val-Trp-Asp-Gly-Thr-Phe-Ser-OH
Disulfide bridges: Cys2-Cys16, Cys9-Cys21, Cys15-Cys28
Length (aa): 35
Formula of ProTx-I: C171H245N53O47S6
Molecular Weight of ProTx-I: 3987.50 Da
Tag: Biotin
Appearance: White lyophilized solid
Solubility: water or saline buffer
CAS number: Not available
Source: Synthetic
Purity rate: > 95 %

Two tarantula peptides inhibit activation of multiple sodium channels

ProTx-I and ProTx-II: gating modifiers of voltage-gated sodium channels

Tarantula toxin ProTx-I differentiates between human T-type voltage-gated Ca2+ Channels Cav3.1 and Cav3.2

A Tarantula-Venom Peptide Antagonizes the TRPA1 Nociceptor Ion Channel by Binding to the S1-S4 Gating Domain

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