Functional analysis of two Kir6.2 (KCNJ11) mutations, K170T and E322K, causing neonatal diabetes. by Tarasov, A, Girard, C, Larkin, B, Tammaro, P, Flanagan, SE, Ellard, S, Ashcroft, F

“…K(ATP) channels were expressed in Xenopus oocytes, and the heterozygous state was simulated by coexpression of wild-type and mutant Kir6.2 with SUR1 (the beta cell type of sulphonylurea receptor (SUR)). …”

A novel mutation causing DEND syndrome: a treatable channelopathy of pancreas and brain. by Shimomura, K, Horster, F, De Wet, H, Flanagan, SE, Ellard, S, Hattersley, A, Wolf, N, Ashcroft, F, Ebinger, F

“…We carried out electrophysiologic analysis of wild-type and mutant K(ATP) channels heterologously expressed in Xenopus oocytes. RESULTS: We identified a novel Kir6.2 mutation (I167L) causing DEND syndrome. …”

An in-frame deletion in Kir6.2 (KCNJ11) causing neonatal diabetes reveals a site of interaction between Kir6.2 and SUR1. by Craig, T, Shimomura, K, Holl, R, Flanagan, SE, Ellard, S, Ashcroft, F

“…DESIGN: Wild-type and mutant Kir6.2/SUR1 channels were examined by heterologous expression in Xenopus oocytes. RESULTS: The Kir6.2-28Delta32 mutation produced a significant decrease in ATP inhibition and an increase in whole-cell K(ATP) currents, explaining the diabetes of the patient. …”

A Kir6.2 mutation causing severe functional effects in vitro produces neonatal diabetes without the expected neurological complications. by Tammaro, P, Flanagan, SE, Zadek, B, Srinivasan, S, Woodhead, H, Hameed, S, Klimes, I, Hattersley, A, Ellard, S, Ashcroft, F

“…Functional properties of wild-type and mutant channels were examined by electrophysiology in Xenopus oocytes. RESULTS: Heterozygous (het) and homozygous L164P K(ATP) channels showed a marked reduction in channel inhibition by ATP. …”

Switching from insulin to oral sulfonylureas in patients with diabetes due to Kir6.2 mutations. by Pearson, E, Flechtner, I, Njølstad, P, Malecki, M, Flanagan, SE, Larkin, B, Ashcroft, F, Klimes, I, Codner, E, Iotova, V, Slingerland, A, Shield, J, Robert, J, Holst, J, Clark, P, Ellard, S, Søvik, O, Polak, M, Hattersley, A

“…The response of mutant K(ATP) channels to the sulfonylurea tolbutamide was assayed in xenopus oocytes. RESULTS: A total of 44 patients (90 percent) successfully discontinued insulin after receiving sulfonylureas. …”

Mutations of the same conserved glutamate residue in NBD2 of the sulfonylurea receptor 1 subunit of the KATP channel can result in either hyperinsulinism or neonatal diabetes. by Männikkö, R, Flanagan, SE, Sim, X, Segal, D, Hussain, K, Ellard, S, Hattersley, A, Ashcroft, F

“…Wild-type and mutant K_ATP channels were expressed in <em>Xenopus laevis</em> oocytes and studied with electrophysiological methods.…”