IS3 peptide‐formed ion channels in rat skeletal muscle cell membranes

FEBS Letters

Bao, Lin¹  Zhou, Pei-Ai¹  Zhang, Ren-Ji¹  Jiang, Yun²  Sha, Yin-Lin²  Miao, Zhen-Wei²  Tang, You-Chi² 

[1] College of Life Sciences, Peking University, Beijing 100871, PR China;College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, PR China

关键词: Synthetic peptide;    IS3 channel;    Na+ selective channel;    Single channel recording;    Cultured rat myotube membrane;    IS3 peptide;    a synthetic peptide corresponding to the transmembrane segment 3 of repeat I from rat brain Na+ channel type I;   

DOI  :  10.1016/S0014-5793(99)00249-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A 22-mer peptide, identical to the primary sequence of domain I segment 3 (IS3) of rat brain sodium channel I, was synthesized. With the patch clamp cell-attached technique, single channel currents could be recorded from the patches of cultured rat myotube membranes when the patches were held at hyperpolarized potentials and the electrode solution contained NaCl and 1 μM IS3, indicating that IS3 incorporated into the membranes and formed ion channels. The single channel conductances of IS3 channels were distributed heterogeneously, but mainly in the range of 10–25 pS. There was a tendency that the mean open time and open probability of IS3 channels increased and the mean close time decreased with the increasing of hyperpolarized membrane potentials. IS3 channels are highly selective for Na⁺ and Li⁺ but not for Cl⁻ and K⁺, similar to the authentic Na⁺ channels.

【 授权许可】

Unknown