Shaker and ether-à-go-go K+ channel subunits fail to coassemble in Xenopus oocytes.
Members of different voltage-gated K+ channel subfamilies usually do not form heteromultimers. However, coassembly between Shaker and ether-à-go-go (eag) subunits, members of two distinct K+ channel subfamilies, was suggested by genetic and functional studies (Zhong and Wu. 1991. Science. 252: 1562-1564; Chen, M.-L., T. Hoshi, and C.-F. Wu. 1996. Neuron. 17:535-542). We investigated whether Shaker and eag form heteromultimers in Xenopus laevis oocytes using electrophysiological and biochemical approaches. Coexpression of Shaker and eag subunits produced K+ currents that were virtually identical to the sum of separate Shaker and eag currents, with no change in the kinetics of Shaker inactivation. According to the results of dominant negative and reciprocal coimmunoprecipitation experiments, the Shaker and eag proteins do not interact. We conclude that Shaker and eag do not coassemble to form heteromultimers in Xenopus oocytes.
Tang
C Y
CY
Department of Physiology, UCLA School of Medicine 90095-1751, USA.
Schulteis
C T
CT
Jiménez
R M
RM
Papazian
D M
DM
D000818:Animals; D055592:Biophysical Phenomena; D001703:Biophysics; D051638:Ether-A-Go-Go Potassium Channels; D005260:Female; D015870:Gene Expression; D066298:In Vitro Techniques; D007700:Kinetics; D046911:Macromolecular Substances; D009865:Oocytes / Q000378:metabolism; D015221:Potassium Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D018075:RNA, Complementary / Q000008:administration & dosage / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D051637:Shaker Superfamily of Potassium Channels; D014982:Xenopus laevis
D051638:Ether-A-Go-Go Potassium Channels; D046911:Macromolecular Substances; D015221:Potassium Channels; D018075:RNA, Complementary; D011994:Recombinant Proteins; D051637:Shaker Superfamily of Potassium Channels