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

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

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism*
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Blotting, Northern
  • Cloning, Molecular
  • DNA, Complementary
  • Molecular Sequence Data
  • Potassium Channels / genetics*
  • Potassium Channels, Inwardly Rectifying*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Sequence Homology, Amino Acid
  • Sequence Homology, Nucleic Acid
  • Xenopus

Substances

  • DNA, Complementary
  • Kcnj1 protein, rat
  • Potassium Channels
  • Potassium Channels, Inwardly Rectifying
  • RNA, Messenger
  • Adenosine Triphosphate