Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

A cDNA clone encoding an inwardly-rectifying potassium channel subunit (Kir6.2) was isolated from an insulinoma cDNA library. The mRNA is strongly expressed in brain, skeletal muscle, cardiac muscle and in insulinoma cells, weakly expressed in lung and kidney and not detectable in spleen, liver or testis. Heterologous expression of Kir6.2 in HEK293 cells was only observed when the cDNA was cotransfected with that of the sulphonylurea receptor (SUR). Whole-cell Kir6.2/SUR currents were K(+)-selective, time-independent and showed weak inward rectification. They were blocked by external barium (5 mM), tolbutamide (Kd = 4.5 microM) or quinine (20 microM) and by 5 mM intracellular ATP. The single-channel conductance was 73 pS. Single-channel activity was voltage-independent and was blocked by 1 mM intracellular ATP or 0.5 mM tolbutamide. We conclude that the Kir6.2/SUR channel complex comprises the ATP-sensitive K-channel.

Original publication

DOI

10.1016/0014-5793(95)01369-5

Type

Journal article

Journal

FEBS Lett

Publication Date

27/12/1995

Volume

377

Pages

338 - 344

Keywords

ATP-Binding Cassette Transporters, Adenosine Triphosphate, Amino Acid Sequence, Animals, Brain, DNA, Complementary, Electric Conductivity, Electrophysiology, Gene Library, Insulinoma, Islets of Langerhans, Mice, Molecular Sequence Data, Muscle, Skeletal, Myocardium, Potassium Channel Blockers, Potassium Channels, Potassium Channels, Inwardly Rectifying, Receptors, Drug, Sequence Analysis, DNA, Sequence Homology, Amino Acid, Sulfonylurea Receptors, Tissue Distribution, Transfection