SURI and Kir6.1 subunits of K(ATP)-channels are co-localized in retinal glial (Müller) cells.
ATP-sensitive potassium channels (K(ATP)), unlike other inwardly rectifying potassium (Kir) channels, require two structurally diverse subunits to form functional channels: one member of the Kir6 channel family (Kir6.1 or Kir6.2), and one sulfonylurea receptor (SUR) of the ATP-binding cassette superfamily (SURI, SUR2A or SUR2B). We have previously shown that two pore-forming subunits of K(ATP)-channels are differently distributed in frog retina. Kir6.1 is localized in Miller (glial) cells, whereas Kir6.2 is found in neurons. Using immunocytochemistry, the present study reveals that in adult frog retina, SURI is restricted to Müller (glial) cells whereas SUR2A and SUR2B are found in neurons. These data suggest that functional K(ATP) channels in Müller cells may be formed by Kir6.1/SURI, and in neurons by Kir6.2/SUR2A and/or Kir6.2/SUR2B.
Eaton
Misty J
MJ
CMBN, Department of Biochemistry, Universidad Central del Caribe, Bayamén, PR, 00960-6032, USA.
Skatchkov
Serguei N
SN
Brune
Andreas
A
Biedermann
Bernd
B
Veh
Rüdiger W
RW
Reichenbach
Andreas
A
D018528:ATP-Binding Cassette Transporters; D000818:Animals; D009457:Neuroglia / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D015221:Potassium Channels / Q000378:metabolism*; D024661:Potassium Channels, Inwardly Rectifying / Q000378:metabolism*; D011894:Rana pipiens; D011955:Receptors, Drug / Q000378:metabolism*; D012160:Retina / Q000166:cytology / Q000378:metabolism*; D064233:Sulfonylurea Receptors; D014018:Tissue Distribution
D018528:ATP-Binding Cassette Transporters; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D011955:Receptors, Drug; D064233:Sulfonylurea Receptors