Efficient expression of rat brain type IIA Na+ channel alpha subunits in a somatic cell line

Neuron. 1992 Jan;8(1):59-70. doi: 10.1016/0896-6273(92)90108-p.

Abstract

Type IIA rat brain Na+ channel alpha subunits were expressed in CHO cells by nuclear microinjection or by transfection using a vector containing both metallothionein and bacteriophage SP6 promoters. Stable cell lines expressing Na+ channels were isolated, and whole-cell Na+ currents of 0.9-14 nA were recorded. The mean level of whole-cell Na+ current (4.5 nA) corresponds to a cell surface density of approximately 2 channels active at the peak of the Na+ current per microns 2, a density comparable to that observed in the cell bodies of central neurons. The expressed Na+ channels had the voltage dependence, rapid activation and inactivation, and rapid recovery from inactivation characteristic of Na+ channels in brain neurons, bound toxins at neurotoxin receptor sites 1 and 3 with normal properties, and were posttranslationally processed to a normal mature size of 260 kd. Expression of Na+ channel cDNA in CHO cells driven by the metallothionein promoter accurately and efficiently reproduces native Na+ channel properties and provides a method for combined biochemical and physiological analysis of Na+ channel structure and function.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Blotting, Northern
  • Brain Chemistry*
  • CHO Cells
  • Cell Nucleus / physiology
  • Cricetinae
  • DNA / chemistry
  • DNA / genetics
  • Electric Conductivity
  • Gene Expression*
  • Macromolecular Substances
  • Microinjections
  • Molecular Sequence Data
  • Plasmids
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Receptors, Cholinergic / metabolism
  • Saxitoxin / metabolism
  • Saxitoxin / pharmacology
  • Sodium Channels / genetics*
  • Sodium Channels / physiology
  • Tetrodotoxin / metabolism
  • Tetrodotoxin / pharmacology
  • Transfection

Substances

  • Macromolecular Substances
  • RNA, Messenger
  • Receptors, Cholinergic
  • Sodium Channels
  • Saxitoxin
  • Tetrodotoxin
  • DNA