Overview
Alternative Name K+ channel toxin ShK, Toxin κ-stichotoxin-She3a, Kappa-stichotoxin-She3a, κ-SHTX-She3a
Lyophilized Powder yes
Origin Modified synthetic peptide originated from Stichodactyla helianthus (Caribbean sea anemone).
MW: ~4627 Da
Purity: >99% (HPLC)
Form Lyophilized powder.
Effective concentration 1-100 nM.
Sequence RSCIDTIPKSRCTAFQCKHSMKYRLSFCRKTCGTC.
Modifications Cys3-Cys35, Cys12-Cys28, Cys17-Cys32.
Label ATTO-590. ATTO dyes are characterized by strong absorption (high extinction coefficient), high fluorescence quantum yield, and high photo-stability. ATTO-590 maximum absorption is 593 nm and maximum fluorescence is at 622 nm. The fluorescence is excited most efficiently in the 575-610 nm range. The extent of labeling is 1 molecule of dye per molecule ShK.
Structure
Activity Stichodactyla Toxin blocks KV1.3, KV1.1, KV1.4, and KV1.6 at subnanomolar concentrations and KV3.2 channels at 1000-fold higher concentration than that required to inhibit KV1.3 channels1-3.
References-Activity
- Pennington, M.W. et al. (1995) Int. J. Pept. Protein Res. 46, 354.
- Beeton, C. et al. (2003) J. Biol. Chem. 278, 9928.
- Middleton, R.E. et al. (2003) Biochemistry 42, 13698.
Accession number P29187.
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 (10000 x g 5 min).
Storage of solutions Up to two weeks at 4°C or three months at -20°C.
Our bioassay
Live cell imaging of Stichodactyla Toxin-ATTO Fluor-590 in differentiated PC-12 cells.Neurite outgrowth was induced in PC12 cells through 10 days exposure to 100 ng/ml Native mouse NGF 2.5S protein (>95%) (#N-100). (A,D) CellMask™ Actin 1X solution was applied for 30 minutes, resulting in a green fluorescence to visualize cellular membrane. (B,E) Following this, the same cells underwent incubation with 0.3 µM of Stichodactyla Toxin-ATTO Fluor-590 for 10 minutes at 370C, followed by PBSX1 wash, leading to red fluorescence indicative of the distribution of KV channels. (C,F) Live imaging of the differentiated PC-12 cells allowed observation of Stichodactyla toxin distribution among the cells.
Binding of Stichodactyla Toxin-ATTO Fluor-590 to Purkinje cells in the rat cerebellum.Lightly-fixed floating rat brain sections were labeled with Stichodactyla Toxin-ATTO Fluor-590 (#STS-400-AR), (100 nM). A. Staining of Purkinje cells in the cerebellum (arrows). B. Staining of neurons in the deep cerebellar nuclei (arrows). DAPI is used as the counterstain (blue).
Direct flow cytometry of Stichodactyla Toxin in live intact rat PC-12 cells.___ PC-12 cells.
___ PC-12 cells + 0.1 µM ShK (Stichodactyla Toxin) (#STS-400).
___ PC-12 cells + 0.1 µM Stichodactyla Toxin-ATTO Fluor-590 (#STS-400-AR).
Direct flow cytometry of Stichodactyla Toxin in PC-12-derived extracellular vesicles (EVs).___ PC-12-derived EVs.
___ PC-12-derived EVs + 50 nM ShK (Stichodactyla Toxin) (#STS-400).
___ PC-12-derived EVs + 50 nM Stichodactyla Toxin-ATTO Fluor-590 (#STS-400-AR).
Alomone Labs Stichodactyla Toxin-ATTO Fluor-590 blocks KV1.3 channels expressed in Xenopus oocytes.A. Representative time course of Stichodactyla Toxin-ATTO Fluor-590 (#STS-400-AR) inhibition of KV1.3 current. Membrane potential was held at -100 mV, current was elicited by a 100 ms voltage ramp to +60 mV every 10 sec, and significantly inhibited by 10 nM Stichodactyla Toxin-ATTO Fluor-590 (green). B. Superimposed traces of KV1.3 current after application of control (black) and of 10 nM Stichodactyla Toxin-ATTO Fluor-590 (green), taken from the recording in A.
Scientific background
ShK (Stichodactyla Toxin) is a peptide toxin originally isolated from the nematocyst of the sea anemone Stichodactyla helianthus1.
ShK blocks KV1.3, KV1.1, KV1.4, and KV1.6 at subnanomolar concentrations and KV3.2 channels at 1000-fold higher concentration than that required to inhibit KV1.3 channels. It has been shown to block KV current in DRG neurons, to displace radioactive Dendrotoxin from brain synaptosomes1 and inhibit I125-Charybdotoxin binding to Jurkat T lymphocytes with an IC50 of 32 pM2,4.
Evidence also suggests that native KV currents in the central nervous system, which are predominantly carried by KV1.2 channels, are highly sensitive to this toxin5.
A fluorescently labeled synthetic ShK is used to recognize and to sort KV1.3 containing lymphocytes4,6.
Target KV1.1, KV1.3, KV1.4, KV1.6 channels
Peptide Content: 100%
Lyophilized Powder
For research purposes only, not for human use
Last Update: 18/11/2024
Specifications
Citations
Citations
