用针对钠离子和钾离子通道信使核糖核酸的互补脱氧核糖核酸探针阻断非洲爪蟾卵母细胞中的离子通道表达。

Blockade of ion channel expression in Xenopus oocytes with complementary DNA probes to Na+ and K+ channel mRNAs.

作者信息

Lotan I, Volterra A, Dash P, Siegelbaum S A, Goelet P

机构信息

Department of Pharmacology, Howard Hughes Medical Institute, Columbia University, New York, New York 10032.

出版信息

Neuron. 1988 Dec;1(10):963-71. doi: 10.1016/0896-6273(88)90153-5.

DOI:10.1016/0896-6273(88)90153-5

PMID:2856090

Abstract

Ionic currents were recorded from Xenopus oocytes injected with RNA isolated from chick or mouse brain. Three currents were studied: a rapid tetrodotoxin-sensitive Na+ current (Ina), an early outward K+ current sensitive to 4-aminopyridine (IA), and an inward current activated by the excitatory amino acid receptor agonist kainate. Oligonucleotides (60-80 bases long) complementary to rat brain Na+ channel sequences were prehybridized to chick brain RNA. These DNA sequences, upon injection into oocytes, specifically inhibited expression of INa relative to IA and the kainate-induced current in a dose-dependent manner. By contrast, prehybridization of oligonucleotides complementary to sequences either from the Drosophila Shaker locus (which codes for an early K+ current in Drosophila muscle) or from a homologous clone from mouse brain did not block the expression of the early outward K+ current induced in the oocytes by mRNA from chick or mouse brain. This method provides a convenient means for testing the functional role of cloned DNA species.

摘要

从注射了从鸡或小鼠大脑中分离出的RNA的非洲爪蟾卵母细胞中记录离子电流。研究了三种电流：一种对河豚毒素敏感的快速Na⁺电流（Ina）、一种对4-氨基吡啶敏感的早期外向K⁺电流（IA）以及一种由兴奋性氨基酸受体激动剂海人酸激活的内向电流。与大鼠脑Na⁺通道序列互补的寡核苷酸（60 - 80个碱基长）与鸡脑RNA进行预杂交。将这些DNA序列注射到卵母细胞中后，相对于IA和海人酸诱导的电流，它们以剂量依赖的方式特异性抑制Ina的表达。相比之下，与果蝇Shaker基因座（其编码果蝇肌肉中的早期K⁺电流）的序列或来自小鼠脑的同源克隆序列互补的寡核苷酸预杂交，并不会阻断由鸡或小鼠脑mRNA在卵母细胞中诱导产生的早期外向K⁺电流的表达。这种方法为测试克隆DNA物种的功能作用提供了一种便捷手段。