Blocks both human ERG1/Kv11.1/KCNH2 potassium channels (in a reversible manner) (PubMed:14599291) and A-type voltage-gated potassium channels Kv4/KCND (in an irreversible manner) (PubMed:11457451, PubMed:12473099, PubMed:12637022). The presence of the Kv4-associated proteins DPP6 or DPP10 is mandatory to have high-affinity blockade of Kv4.2/KCND2 and Kv4.3/KCND3 channels (By similarity). In contrast, the presence of the Kv4-associated protein KChIP1/KCNIP1 does not enhance the affinity blockade (By similarity). May dispose of two functional faces (A and B); the two basic residues (Arg-40 and Lys-41) on the alpha-helix side of the peptide that blocks the hERG current (face A) and the typical dyad through which it blocks A-type currents on the beta-sheet side (face B) (PubMed:14599291). In adult rat brain, it binds to sites in the striatum, hippocampus, superior colliculus, and cerebellum. It shares the same target in rat brain than AaTX1 (AC Q867F4) and AmmTX3 (AC P60208). In DPP6 knockout mice, A-type currents are much less affected by the toxin than in wild-type mice (PubMed:23440961). Expressed by the venom gland. Has the structural arrangement of an alpha-helix connected to a beta-sheet by disulfide bonds (CSalpha/beta). Has no effect on Kv1.1/KCNA1, Kv1.2/KCNA2, Kv1.3/KCNA3, Kv7.1/KCNQ1, Kv7.1/KCNQ1+minK, and on Kir2.1/KCNJ2. Belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 15 subfamily.