Characterization of a potassium channel toxin from the Caribbean Sea anemone Stichodactyla helianthus
Castañeda, Sotolongo, Amor, Stöcklin, Anderson, Harvey, Engström, Wernstedt, Karlsson (1995) Characterization of a potassium channel toxin from the Caribbean Sea anemone Stichodactyla helianthus Toxicon (IF: 2.6) 33(5) 603-13Abstract
A peptide toxin, ShK, that blocks voltage-dependent potassium channels was isolated from the whole body extract of the Caribbean sea anemone Stichodactyla helianthus. It competes with dendrotoxin I and alpha-dendrotoxin for binding to synaptosomal membranes of rat brain, facilities acetylcholine release at an avian neuromuscular junction and suppresses K+ currents in rat dorsal root ganglion neurones in culture. Its amino acid sequence is R1SCIDTIPKS10RCTAFQCKHS20MKYRLSFCRK30TCGTC35. There is no homology with other K+ channel-blocking peptides, except for BgK from the sea anemone Bunodosoma granulifera. ShK and BgK appear to be in a different structural class from other toxins affecting K+ channels.
Links
http://www.ncbi.nlm.nih.gov/pubmed/7660365http://dx.doi.org/10.1016/0041-0101(95)00013-c
