guangxitoxin-1E

Guangxitoxin-1E (GxTx-1E) is a 36-amino acid peptidyl neurotoxin originally isolated from the venom of the tarantula *Plesiophrictus guangxiensis* (also known as *Chilobrachys guangxiensis*). It acts as a potent and selective gating modifier of voltage-gated potassium channels, primarily targeting Kv2.1 (KCNB1) and Kv2.2 (KCNB2) with nanomolar affinity, and to a lesser extent Kv4.3 (KCND3). By binding to the voltage-sensing domains of these channels, guangxitoxin-1E shifts their activation to more depolarized potentials, effectively inhibiting potassium efflux. In pancreatic beta cells, this blockade broadens action potentials, enhances glucose-stimulated calcium oscillations, and increases insulin secretion. Guangxitoxin-1E is widely utilized as a research-use-only (RUO) laboratory tool to investigate the physiological roles of Kv2 channels in neuronal excitability and endocrine function.

Other names

GxTx-1EGxTx1EGxTx 1Eguangxitoxin 1Eguangxitoxin1Eguangxitoxin-1Eκ-TRTX-Pg1aκ-Theraphotoxin-Pg1a