A NOVEL ATP-DEPENDENT INWARD RECTIFIER POTASSIUM CHANNEL EXPRESSED PREDOMINANTLY IN GLIAL-CELLS

被引：216

作者：

TAKUMI, T

ISHII, T

HORIO, Y

MORISHIGE, K

TAKAHASHI, N

YAMADA, M

YAMASHITA, T

KIYAMA, H

SOHMIYA, K

NAKANISHI, S

KURACHI, Y

机构：

[1] OSAKA UNIV, FAC MED, BIOMED RES CTR, DEPT PHARMACOL 2, SUITA, OSAKA 565, JAPAN

[2] OSAKA UNIV, FAC MED, BIOMED RES CTR, DEPT OBSTET & GYNECOL, SUITA, OSAKA 565, JAPAN

[3] OSAKA UNIV, FAC MED, BIOMED RES CTR, DEPT NEUROANAT, SUITA, OSAKA 565, JAPAN

[4] KYOTO UNIV, FAC MED, INST IMMUNOL, KYOTO 60601, JAPAN

来源：

JOURNAL OF BIOLOGICAL CHEMISTRY | 1995年 / 270卷 / 27期

关键词：

D O I：

10.1074/jbc.270.27.16339

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

We have isolated a novel inward rectifier K+ channel predominantly expressed in glial cells of the central nervous system. Its amino acid sequence exhibited 53% identity with ROMK1 and approximately 40% identity with other inward rectifier K+ channels. Xenopus oocytes injected with cRNA derived from this clone expressed a K+ current, which showed classical inward rectifier K+ channel characteristics. Intracenular Mg . ATP was required to sustain channel activity in excised membrane patches, which is consistent with a Walker type-ii ATP-binding domain on this clone. We designate this new clone as K-AB-2 (the second type of inward rectifying K+ channel with an ATP-binding domain). In situ hybridization showed K-AB-2 mRNA to be expressed predominantly in glial cells of the cerebellum and forebrain. This is the first description of the cloning of a glial cell inward rectifier potassium channel, which may be responsible for K+ buffering action of glial cells in the brain.

引用

页码：16339 / 16346

页数：8