Imperatoxin-A

Non Antibodies

Ryanodine receptors

The product is shipped as a lyophilized powder at room temperature. Upon receipt, store the product at -20°C. Protect from moisture.

3758 Da

A Ryanodine Receptor Modulator

Centrifuge the vial (10, 000 × g for 5 minutes) before adding solvent 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. Gently tap, tilt, and roll the vial to aid dissolution. Avoid vigorous vortexing; light vortexing for up to 3 seconds is acceptable if needed. The product is soluble in pure water at high micromolar concentrations (100 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.

7, 4

Pandinus imperator (Emperor scorpion)

10 - 300 nM

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 soluble in pure water at high micromolar concentrations (100 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.

Imperatoxin A (IpTxa) is a 33 amino acid natural peptidyl toxin isolated from the venom of scorpion Pandinus imperator. IpTxa interacts specifically and activates the sarcoplasmic reticulum Ca2+-release channel of skeletal and cardiac muscle (ryanodine receptor 1 and 2). It reversibly enhances binding of ryanodine to the receptors. The activating effect of IpTxa on skeletal ryanodine receptor is Ca2+-dependent, synergized by caffeine, and independent of other modulators of RyRs1-3.IpTxa increased the open probability of rabbit skeletal muscle RyRs by increasing the frequency of open events and decreasing the duration of the closed lifetimes.2IpTxa displays structural homology with an activating segment of the a1 subunit of the skeletal dihydropyridine receptor (II-III loop, segment Glu666-Leu690) which is putatively the native activator of ryanodine receptor. IpTxa and the segment Glu666-Leu690 activate RyRs in a similar manner and appear to compete for a common binding site on the ryanodine channel protein4. This suggest a common mechanism of IpTxa and dihydropyridine receptor for modulation of RyR4.