Overview
Alternative Name M-TRTx-Gr1a, M-theraphotoxin-Gr1a, GsMTx4
Lyophilized Powder yes
Origin Grammostola rosea (Chilean rose) tarantula
Source Synthetic modified peptide
MW: 4723 Da
Form Lyophilized from double distilled water (ddH2O). May contain TFA as a residual counter ion.
Effective concentration 0.1 µM – 5 µM
Sequence GCLEFWWKCNPNDDKCCRPKLKCSKLFKLCNFSF-NH2
Modifications Phe34 - C-terminal amidation
ATTO Fluor-647N
Disulfide bonds between: Cys2-Cys17, Cys9-Cys23, and Cys16-Cys30
ATTO Fluor-647N
Disulfide bonds between: Cys2-Cys17, Cys9-Cys23, and Cys16-Cys30
Label ATTO-647N. ATTO dyes are characterized by strong absorption (high extinction coefficient), high fluorescence quantum yield, and high photo-stability. Maximum absorption 646 nm; maximum fluorescence 664 nm. The fluorescence is excited most efficiently in the range 625 - 660 nm. A suitable excitation source is the 647 nm line of the Krypton-Ion laser or a diode-laser emitting at 650 nm. It can be used in flow cytometry (FACS) using the red (637 nm) laser. The extent of labeling is one molecule of dye per one GsMTx-4 molecule.
Structure
Activity GsMTx-4 is an inhibitor of Na+ voltage-gated channels3 and cation-selective mechanosensitive channels1,2.
Shipping and storage The product is shipped as a lyophilized powder at room temperature. Upon receipt, store the product at -20°C. Protect from moisture. Avoid exposure to light.
Solubility Centrifuge the vial before adding solvent (10,000 x g for 5 minutes) to spin down all the powder to the bottom of the vial. The lyophilized product may be difficult to visualize. Add solvent directly to the centrifuged vial. Tap the vial to aid in dissolving the lyophilized product. Tilt and gently roll the liquid over the walls of the vial. Avoid vigorous vortexing. Light vortexing for up to 3 seconds is acceptable if needed. The product is lyophilized in 0.5 ml conical vial. The product is soluble in pure water to high-micromolar concentrations (5 µM - 1 mM). For long-term storage in solution, we recommend preparing a stock solution by dissolving the product in double distilled water (ddH2O) at a concentration between 100-1000x of the final working concentration. Divide the stock solution into small aliquots and store at -20°C. Before use, thaw the relevant vial(s) and dilute to the desired working concentration in your working buffer. Centrifuge all product preparations before use. It is recommended to prepare fresh solutions in working buffers just before use. Avoid multiple freeze-thaw cycles to maintain biological activity. Avoid exposure to light.
Storage of solutions Store the reconstituted solution at -20°C for the shortest time possible. Avoid multiple freeze-thaw cycles. We do not recommend storing the product in working solutions for longer than a day. Avoid exposure to light.
Our bioassay
Live cell imaging of GsMTx-4-ATTO Fluor-647N in differentiated PC-12 cells.Neurite outgrowth was induced in PC-12 cells through 10 days exposure to 100 ng/ml Native mouse NGF 2.5S protein (99%) (#N-240). (A-B) CellMask™ Actin 1X solution was applied for 30 minutes at 37ºC, resulting in a green fluorescence to visualize cellular membrane. (C-D) Following this, the same cells underwent incubation with 0.1 µM of GsMTx-4-ATTO Fluor-647N (#STG-100-FRN) at 37ºC, leading to red fluorescence indicative of GsMTx-4 binding sites. (E-F) Live imaging of the differentiated PC-12 cells allowed observation of GsMTx-4 distribution among the cells.
Unlabeled GsMTx-4 successfully blocks GsMTx-4-ATTO Fluor-647N binding.Neurite outgrowth was induced in PC-12 cells through 10 days exposure to 100 ng/ml Native mouse NGF 2.5S protein (99%) (#N-240). (A) CellMask™ Actin 1X solution was applied for 30 minutes at 37ºC, resulting in a green fluorescence to visualize cellular membrane. (B) Following this, the same cells underwent incubation with 100 µM of GsMTx-4 (#STG-100) and 0.1 µM of GsMTx-4-ATTO Fluor-647N (#STG-100-FRN) at 37ºC. (C) Live imaging of differentiated PC-12 cells demonstrates that GsMTx-4 successfully competes with GsMTx-4-ATTO Fluor-647N for binding sites.
Expression of GsMTx-4-Biotin in Rat DRG Frozen Sections.(A) Piezo1 (#APC-087) was applied for 60 minutes at 37ºC, followed by staining with goat anti-rabbit AlexaFluor-488, resulting in green fluorescence predominantly in DRG cells. (B) The same frozen sections underwent incubation with 0.3 µM of GsMTx-4-ATTO Fluor-647N (#STG-100-FRN) for 30 minutes at 37ºC, resulting in red fluorescence in DRG cells. (C) Cell nuclei were counterstained with Hoechst 33342, emitting blue fluorescence. (D) Co-localization of Piezo1 and GsMTx-4 in DRG cells (indicated by arrows) demonstrates that GsMTx-4 serves as a reliable biomarker for mechanosensitive channels.
Direct flow cytometry of GsMTx-4 in live intact rat PC-12 cells.___ PC-12 cells.
___ PC-12 cells + 0.1 µM GsMTx-4 (#STG-100).
___ PC-12 cells + 0.1 µM GsMTx-4 -ATTO Fluor-647N (#STG-100-FRN).
Alomone Labs GsMTx-4-ATTO Fluor-647N inhibits NaV1.7 channel currents heterologously expressed in Xenopus oocytes.A. Representative time course of GsMTx-4-ATTO Fluor-647N (#STG-100-FRN) 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 significantly inhibited by application of 0.5 μM GsMTx-4-ATTO Fluor-647N (green).
B. Superimposed traces of NaV1.7 channel currents in the absence (control) and presence (green) of 0.5 μM GsMTx-4-ATTO Fluor-647N (taken from the recording in A).
Scientific background
GsMTx-4 is a 34 amino acid peptidyl toxin originally isolated from the Grammostola rosea (Chilean rose) tarantula venom and belongs to the huwentoxin-1 family1.
This toxin inhibits different channels and in addition has antimicrobial activity. It blocks cation-selective mechanosensitive ion channels (strech-activated channels, SACs), without having an effect on whole-cell voltage-sensitive currents1. In addition, it inhibits atrial fibrillation2 as well as the membrane motor of outer hair cells3 at low doses. A medium toxicity on a large spectra of voltage-gated Na+ channels, namely NaV1.1, NaV1.2, NaV1.3, NaV1.4, NaV1.5, NaV1.6 and NaV1.7 was reported. GsMTx-4 also inhibits K+ channels KV11.1 and KV11.2, whereas it does not inhibit K+ channels KV1.1 (IC50 > 85 µM), KV1.4 (IC50 > 85 µM) and KV11.3 (IC50 = 53 µM)4. GsMTx-4 was also found to inhibit both TRPC1 and TRPC6 channels5,6, as well as Piezo1, the mechanosensitive channel7.
Antimicrobial activity is shown against several Gram-positive and Gram-negative bacteria as well8.
Target NaV1.7 channels, TRPC1, TRPC6, Piezo1
Lyophilized Powder
For research purposes only, not for human use
Last Update: 31/12/2024
Specifications
Citations
Citations
