Microheterogeneity in heteromultimeric assemblies formed by Shaker (Kv1) and Shaw (Kv3) subfamilies of voltage-gated K+ channels.
Single K+ channels were recorded in Xenopus oocytes injected with a 1:1 mixture of mRNAs coding for NGK1 (Kv1.2) and NGK2 (Kv3.1a) voltage-dependent K+ channels. A new class of channels of 18 pS conductance was observed, and was designated as NGK1,2 channels. According to their properties of activation voltages and open life times, four types of NGK1,2 channels with microheterogeneity were detected. The results suggest that voltage-dependent NGK1 Shaker and NGK2 Shaw K+ channels, from different subfamilies, assemble to form heteromultimeric K+ channels, giving rise to a mosaic of characteristics inherited from two parental channels.
Shahidullah
M
M
Department of Biophysics, Neuroinformation Research Institute, Kanazawa University School of Medicine, Japan.
Hoshi
N
N
Yokoyama
S
S
Higashida
H
H
D000818:Animals; D002462:Cell Membrane / Q000502:physiology; D004330:Drosophila / Q000235:genetics / Q000502:physiology; D004553:Electric Conductivity; D005260:Female; D066298:In Vitro Techniques; D015640:Ion Channel Gating; D051663:Kv1.2 Potassium Channel; D008564:Membrane Potentials; D009865:Oocytes / Q000502:physiology*; D015221:Potassium Channels / Q000096:biosynthesis / Q000502:physiology*; D024642:Potassium Channels, Voltage-Gated; D012333:RNA, Messenger / Q000378:metabolism; D051670:Shaw Potassium Channels; D013997:Time Factors; D014158:Transcription, Genetic; D014982:Xenopus laevis
C098254:Kcnc1 protein, rat; D051663:Kv1.2 Potassium Channel; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D012333:RNA, Messenger; D051670:Shaw Potassium Channels