Overview
The exact location of the disulfide bridges is currently unknown.
Centrifuge all products before use (10000 x g 5 min).
Alomone Labs SsdTx3 inhibits Kir6.2/SUR1 channels stably expressed in HEK-293 cells.A. The percent inhibition of KATP channels (comprising Kir6.2 + SUR1 subunits) stably expressed in HEK-293 cells, in the presence of different concentrations of SsdTx3 (#STS-670). The KATP channels were recorded using the whole cell patch clamp technique. An IC50 value of 376 nM was found for Ssd3a in this experiment.
B. A representative cell recording showing the KATP (Kir6.2 + SUR1) currents (I in nA) under control conditions (without toxin) compared to conditions with different concentrations of SsdTx3. The data indicated that the toxin-mediated inhibition was reversible.
SsdTx3 (kappa-scoloptoxin(15)-Ssd3a) is a toxin isolated from the venom of the centipede Scolopendra subspinipes dehaani, a species that inhabits Asia. SsdTx3 was found to be an inhibitor of hKATP channels by blocking the hKir6.2 pore co-expressed with hSUR1. Dose-Response curve of the hKATP channels inhibition revealed that SsdTx3 inhibits hKATP channels with a Kd values of 278nM1.
SsdTx belongs to a family of five proteins, discovered so far from a multiple centipede species, that target hKATP channel by blocking the hKir6.2 pore. They have conserved features of four cysteine residues and a P-P segment that contains positively charged residues important for blocking the K+ pore1.
ATP-sensitive K+ ion channels (KATP channels) can be found in many different tissues such as pancreatic β-cells, carried myocytes, skeletal muscle, smooth muscle and brain. KATP channels are responsible for linking between the cell metabolism and the membrane potential and therefore they are critical for the regulation of different cellular pathways2.
