A sea anemone polypeptide toxin inhibiting the ASIC3 acid-sensitive channel

作者：Kozlov S A^*; Osmakov D I; Andreev Ya A; Koshelev S G; Gladkikh I N; Monastyrnaya M M; Kozlovskaya E P; Grishin E V

来源：Russian Journal of Bioorganic Chemistry, 2012, 38(6): 578-583.

DOI：10.1134/S1068162012060064

• ASIC3 receptors
• electrophysiological studies
• polypeptide toxins
• proton-sensitive channels
• sea anemones

A polypeptide toxin pi-AnmTX Hcr 1b-1 with a molecular mass of 4537 Da was isolated from the whole extract of the sea anemone Heteractis crispa by multistage liquid chromatography. According to a homology search using the BLAST algorithm, the novel toxin was referred to the group of the known sea anemone toxins BDS and APETx with the homology of the amino acid sequence not exceeding 50%. In electrophysiological studies on the receptors expressed in Xenopus laevis oocytes the toxin inhibited the amplitude of the fast component of the integral ASIC3 current. The calculated IC50 value was 5.5 +/- 1.0 mu M. Among the known polypeptide blockers of ASIC3 channels the pi-AnmTX Hcr 1b-1 toxin was the least potent inhibitor, which can be explained, in our opinion, by a small amount of charged amino acid residues in its structure.

• 出版日期2012-11