Sulfonylurea receptor 1 and Kir6.2 expression in the novel human insulin-secreting cell line NES2Y.
NES2Y is a proliferating human insulin-secreting cell line that we have derived from a patient with persistent hyperinsulinemic hypoglycemia of infancy. This disease is characterized by unregulated insulin release despite profound hypoglycemia. NES2Y cells, like beta-cells isolated from the patient of origin, lack functional ATP-sensitive potassium channels (KATP) and also carry a defect in the insulin gene-regulatory transcription factor PDX1. Here, we report that the NES2Y beta-cells that are transfected with the genes encoding the components of KATP channels in beta-cells, sulfonylurea receptor (SUR) 1 and Kir6.2, have operational KATP channels and show normal intracellular Ca2+ and secretory responses to glucose. However, these cells, designated NESK beta-cells, have impaired insulin gene transcription responses to glucose. NES2Y beta-cells that are transfected with either Kir6.2 or SUR1 alone do not express functional KATP channels and have impaired intracellular free Ca2+ concentration-signaling responses to depolarization-dependent beta-cell agonists. These findings document that in NES2Y beta-cells, coexpression of both subunits is critically required for fully operational KATP channels and KATP channel-dependent signaling events. This article further characterizes the properties of the novel human beta-cell line, NES2Y, and documents the usefulness of these cells in diabetes-related research.
Macfarlane
W M
WM
School of Biochemistry and Genetics, University of Newcastle upon Tyne, UK.
O'Brien
R E
RE
Barnes
P D
PD
Shepherd
R M
RM
Cosgrove
K E
KE
Lindley
K J
KJ
Aynsley-Green
A
A
James
R F
RF
Docherty
K
K
Dunne
M J
MJ
D018528:ATP-Binding Cassette Transporters; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling; D002460:Cell Line; D004594:Electrophysiology; D006801:Humans; D007328:Insulin / Q000235:genetics / Q000378:metabolism*; D000078790:Insulin Secretion; D007425:Intracellular Membranes / Q000378:metabolism; D007515:Islets of Langerhans / Q000378:metabolism* / Q000502:physiology; D009994:Osmolar Concentration; D015221:Potassium Channels / Q000235:genetics / Q000378:metabolism*; D024661:Potassium Channels, Inwardly Rectifying; D011955:Receptors, Drug / Q000378:metabolism*; D064233:Sulfonylurea Receptors; D014158:Transcription, Genetic; D014162:Transfection
C577507:ABCC8 protein, human; D018528:ATP-Binding Cassette Transporters; D007328:Insulin; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D011955:Receptors, Drug; D064233:Sulfonylurea Receptors; D002118:Calcium