Effect of tunicamycin on the expression of functional brain neurotransmitter receptors and voltage-operated channels in Xenopus oocytes

doi:10.1016/0169-328X(88)90025-3

Molecular Brain Research

Volume 4, Issue 3, November 1988, Pages 191-199

https://doi.org/10.1016/0169-328X(88)90025-3 Get rights and content

Abstract

The role of N-glycosylation on the expression of functional brain neurotransmitter receptors and voltage-operated channels was studied by injecting Xenopus oocytes with mRNA from rat brain or chick optic lobe, and culturing them in the presence or absence of tunicamycin, an inhibitor of asparagine linked glycosylation. Electrophysiological recordings were then made to assess the amounts of functional receptors and channels present in the oocyte membrane. The appearance of γ-aminobutyric acid (GABA) receptors and voltage-activated Na⁺ channels was profoundly reduced. In contrast, the functional expression of kainate receptors, and voltage-activated K⁺ and Ca²⁺ channels was much less affected. Thus, it seems that kainate receptors, and K⁺ and Ca²⁺ channels can be expressed and function normally without being glycosylated. On the other hand, GABA receptors and Na⁺ channels may need to be N-glycosylated in order to function properly, or to ensure their correct insertion into the membrane.

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Research reportEffect of tunicamycin on the expression of functional brain neurotransmitter receptors and voltage-operated channels in Xenopus oocytes

Abstract

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

Cell

Biochem. Biophys. Res. Commun.

J. Biol. Chem.

Biochem. Biophys. Res. Commun.

J. Biol. Chem.

A transient calcium-dependent chloride current in the immature Xenopus oocyte

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Tunicamycin inhibits the expression of surface sodium channels in cultured muscle cells

J. Cell Physiol.

The influence of topology and glycosylation on the fate of heterologous secretory proteins made in Xenopus oocytes

Eur. J. Biochem.

Control of acetylcholine receptors in skeletal muscle

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α-Aminobutyric acid and benzodiazepine receptors: Copurification and characterization

Serotonin receptors induced by exogenous messenger RNA in Xenopus oocytes

Voltage-operated channels induced by foreign messenger RNA in Xenopus oocytes

Messenger RNA from human brain induces drug- and voltage-activated channels in Xenopus oocytes

Nature (Lond.)

Slowly inactivating potassium channels induced in Xenopus oocytes by messenger ribonucleic acid from Torpedo brain

J. Physiol. (Lond.)

Glutamate and kainate receptors induced by rat brain messenger RNA in Xenopus oocytes

Properties of human brain glycine receptors expressed in Xenopus oocytes

Research report
Effect of tunicamycin on the expression of functional brain neurotransmitter receptors and voltage-operated channels in Xenopus oocytes