一种新型内向整流ATP依赖性钾通道ROMK6（Kir1.1f）的克隆与功能表达

Cloning and functional expression of a novel isoform of ROMK inwardly rectifying ATP-dependent K+ channel, ROMK6 (Kir1.1f).

作者信息

Kondo C, Isomoto S, Matsumoto S, Yamada M, Horio Y, Yamashita S, Takemura-Kameda K, Matsuzawa Y, Kurachi Y

机构信息

Department of Pharmacology II, Faculty of Medicine, Osaka University, Suita, Japan.

出版信息

FEBS Lett. 1996 Dec 9;399(1-2):122-6. doi: 10.1016/s0014-5793(96)01302-6.

DOI:10.1016/s0014-5793(96)01302-6

PMID:8980134

Abstract

We have identified from rat kidney a novel isoform of ROMK/Kir1.1, designated ROMK6/Kir1.1f. ROMK6 was nearly identical to ROMK1, but possessed an 122-bp insertion in the 5' region. Its deduced amino acid sequence was shorter by 19 amino acids than that of ROMK1 in the amino-terminus. Unlike other previously reported ROMK isoforms, ROMK6 mRNA was ubiquitously expressed in various tissues, including kidney, brain, heart, liver, pancreas and skeletal muscle. Xenopus oocytes injected with ROMK6 cRNA expressed a Ba2+-sensitive weakly inwardly rectifying K+ current. These results indicate that ROMK6 is a novel functional K+ channel and might be involved in K+ secretion in various tissue.

摘要

我们已从大鼠肾脏中鉴定出一种新型的ROMK/Kir1.1同工型，命名为ROMK6/Kir1.1f。ROMK6与ROMK1几乎完全相同，但在5'区域有一个122bp的插入片段。其推定的氨基酸序列在氨基末端比ROMK1短19个氨基酸。与其他先前报道的ROMK同工型不同，ROMK6 mRNA在包括肾脏、大脑、心脏、肝脏、胰腺和骨骼肌在内的各种组织中普遍表达。注射了ROMK6 cRNA的非洲爪蟾卵母细胞表达出一种对Ba2+敏感的弱内向整流K+电流。这些结果表明，ROMK6是一种新型的功能性K+通道，可能参与各种组织中的K+分泌。