Sodium channel modulating activity in a δ‐conotoxin from an Indian marine snail

FEBS Letters

Pal, Prajna P²  Balaram, P²  Dhawan, Ritu³  Ramaswami, Mani¹  Sikdar, S.K²  Ramasamy, P²  Sudarslal, S²  Krishnan, K.S¹  Lala, Anil K³  Sarma, Siddhartha P²  Majumdar, Sriparna² 

[1] Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai 400 005, India;Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India;Department of Chemistry, Indian Institute of Technology, Mumbai 400 076, India

关键词: δ-Conotoxin;    Sodium channel;    Conus peptide;    Mass spectrometry;    Conus amadis;   

DOI  :  10.1016/S0014-5793(03)01016-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A 26 residue peptide (Am 2766) with the sequence CKQAGESCDIFSQNCCVG-TCAFICIE-NH₂ has been isolated and purified from the venom of the molluscivorous snail, Conus amadis, collected off the southeastern coast of India. Chemical modification and mass spectrometric studies establish that Am 2766 has three disulfide bridges. C-terminal amidation has been demonstrated by mass measurements on the C-terminal fragments obtained by proteolysis. Sequence alignments establish that Am 2766 belongs to the δ-conotoxin family. Am 2766 inhibits the decay of the sodium current in brain rNav1.2a voltage-gated Na⁺ channel, stably expressed in Chinese hamster ovary cells. Unlike δ-conotoxins have previously been isolated from molluscivorous snails, Am 2766 inhibits inactivation of mammalian sodium channels.

【 授权许可】

Unknown