Do voltage-gated Kv1.1 and inward rectifier Kir2.1 potassium channels form heteromultimers?
Possible heteromultimer formation between Kv- and Kir-type K+ channels was investigated, in connection with the known functional diversity of K+ channels in vivo. Voltage-clamp experiments were performed on Xenopus oocytes, either injected with concatenated Kir2.1-Kv1.1 mRNA, or co-injected with Kv1.1 and Kir2.1 mRNA. K+ currents could be approximated by the algebraic sum of the 2 K+ current types alone. The tandem construct did not show functional expression, although it could be detected by Western blotting. We conclude that Kv1.1 and Kir2.1 alpha-subunit proteins fail to assemble and do not contribute functional diversity to K+ channels.
Tytgat
J
J
University of Leuven, Laboratory of Toxicology, Belgium. jan.tytgat@med.kuleuven.ac.be
Buyse
G
G
Eggermont
J
J
Droogmans
G
G
Nilius
B
B
Daenens
P
P
D000818:Animals; D015153:Blotting, Western; D003001:Cloning, Molecular; D015870:Gene Expression; D015640:Ion Channel Gating / Q000502:physiology*; D009865:Oocytes; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D024661:Potassium Channels, Inwardly Rectifying; D011487:Protein Conformation; D012333:RNA, Messenger / Q000378:metabolism; D014982:Xenopus laevis
D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D012333:RNA, Messenger