Psalmotoxin 1  (Synonyms: PcTx1; Psalmopoeus cambridgei toxin-1)

Psalmotoxin 1 (PcTx1) is a protein toxin that can bind at subunit-subunit interfaces of acid-sensing ion channel 1a (ASIC1a). Psalmotoxin 1 is a potent and slective ASIC1a inhibitor (IC₅₀: 0.9 nM) by increasing the apparent affinity for H⁺ of ASIC1a. Psalmotoxin 1 can induce cell apoptosis, also inhibits cell migration, proferliration and invasion of cancer cells. Psalmotoxin 1 can be used in the research of cancers, or neurological disease^[1][3][4][6].

IC50: 0.9 nM (ASIC1a), 50 nM (ASIC1b, ASIC2a, and ASIC3)^[6].

Psalmotoxin 1 (20 nM, 125 s) inhibits ASIC1a currents by drastically shifting the steady-state desensitization curve to lower H⁺ concentrations^[1].
? Psalmotoxin 1 (30 nM) competes with Ca²⁺ in binding to ASIC1a channels^[1].
? Psalmotoxin 1 (100 or 200 ng, 24-72 h) significantly weakens the migration, proliferation and invasion of MCF-7 and MDA-MB-231 cells^[4].
? Psalmotoxin 1 (100 ng/mL, 24 h) significantly inhibits acid-induced increases in intracellular calcium and LDH release, induces cell apoptosis and cell cycle arrest in nucleus pulposus cells (NPCs)^[5].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Psalmotoxin 1 (i.c.v., 1 ng/kg, a single dose) is neuroprotective in a conscious model of stroke via direct inhibition of ASIC1a^[2].
? Psalmotoxin 1 (tail vein injection, 10 ng/kg, daily for 7 days) inhibits tumor growth in breast cancer mice model^[4].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

4689.39

C₂₀₀H₃₁₂N₆₂O₅₇S₆

880107-52-8

Solid

White to off-white

Glu-Asp-Cys-Ile-Pro-Lys-Trp-Lys-Gly-Cys-Val-Asn-Arg-His-Gly-Asp-Cys-Cys-Glu-Gly-Leu-Glu-Cys-Trp-Lys-Arg-Arg-Arg-Ser-Phe-Glu-Val-Cys-Val-Pro-Lys-Thr-Pro-Lys-Thr (Disulfide bridge: Cys3-Cys18, Cys10-Cys23, Cys17-Cys33)

EDCIPKWKGCVNRHGDCCEGLECWKRRRSFEVCVPKTPKT (Disulfide bridge: Cys3-Cys18, Cys10-Cys23, Cys17-Cys33)

Room temperature in continental US; may vary elsewhere.

Sealed storage, away from moisture

*In solvent : -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture)

• [1]. Chen X, et al. The tarantula toxin psalmotoxin 1 inhibits acid-sensing ion channel (ASIC) 1a by increasing its apparent H⁺ affinity. J Gen Physiol. 2005 Jul;126(1):71-9.  [Content Brief]

  [2]. Claudia A McCarthy, et al. PcTx1 affords neuroprotection in a conscious model of stroke in hypertensive rats via selective inhibition of ASIC1a. Neuropharmacology. 2015 Dec;99:650-7.  [Content Brief]

  [3]. Niko Joeres, et al. Functional and pharmacological characterization of two different ASIC1a/2a heteromers reveals their sensitivity to the spider toxin PcTx1. Sci Rep. 2016 Jun 9;6:27647. doi: 10.1038/srep27647.  [Content Brief]

  [4]. Chao Yang, et al. Overexpression of acid-sensing ion channel 1a (ASIC1a) promotes breast cancer cell proliferation, migration and invasion. Transl Cancer Res. 2020 Dec;9(12):7519-7530.  [Content Brief]

  [5]. Feng Cai, et al. Acid-sensing ion channel 1a regulates the survival of nucleus pulposus cells in the acidic environment of degenerated intervertebral discs. Iran J Basic Med Sci. 2016 Aug;19(8):812-820.  [Content Brief]

  [6]. P Escoubas, et al. Isolation of a tarantula toxin specific for a class of proton-gated Na+ channels. J Biol Chem. 2000 Aug 18;275(33):25116-21.  [Content Brief]