Dual-function toxin that inhibits both serine proteases (trypsin) and voltage-gated potassium channels (Kv). The toxin is more active on Kv1.1/KCNA1 (78% inhibition), than on Kv1.2/KCNA2 (10% inhibition), and Kv1.3/KCNA3 (28% inhibition), although a high dose (5 uM) is needed. The inhibition of potassium channels is voltage-dependent. Expressed by the venom gland. LD(50) is 256 +/- 23 ug/kg by injection into the fourth ventricle of the adult mouse brain. Belongs to the venom Kunitz-type family. 02 (native) subfamily.