Insertion of a SNS‐specific tetrapeptide in S3–S4 linker of D4 accelerates recovery from inactivation of skeletal muscle voltage‐gated Na channel μ1 in HEK293 cells

FEBS Letters

Waxman, S.G¹  Cummins, T.R¹  Ishikawa, K¹  Dib-Hajj, S.D¹ 

[1] Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA

关键词: Voltage dependence;    Na current kinetics;    Channel repriming;    TTX;   

DOI  :  10.1016/S0014-5793(97)01154-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Na channel subunits αSNS (PN3) and αμ1(SkM1) produce slowly inactivating/TTX-resistant and rapidly inactivating/TTX-sensitive currents, respectively. αSNS (PN3) current recovers from inactivation (reprimes) rapidly. Sequence alignment identified the tetrapeptide SLEN, in the S3–S4 linker of D4, as αSNS-specific. To determine whether SLEN endows Na channels with slow kinetics and/or rapid repriming, we analyzed the transient Na current produced by a chimera μ1SLEN in HEK293 cells. Neither kinetics nor voltage dependence of activation and inactivation was affected. However, repriming was twice as fast as in the wild type at −100 mV. This suggests that SLEN may contribute to the rapid repriming of TTX-resistant Na current.

【 授权许可】

Unknown