Molecular cloning and functional expression of a novel potassium channel beta-subunit from human atrium.
We report the cloning and functional expression of a novel K+ channel beta-subunit from human atrium, hKv beta 3. hKv beta 3 is highly homologous to the two beta-subunits cloned from rat brain, Kv beta 1 and Kv beta 2, but has an essentially unique stretch of 79 N-terminal residues. Upon expression in Xenopus oocytes, hKv beta 3 accelerates the inactivation of co-injected hKv1.4 currents and induces fast inactivation of non-inactivating co-injected hKv1.5 currents. By contrast, hKv beta 3 had no effect on hKv1.1, hKv1.2, or hKv2.1 currents. Thus, hKv beta 3 represents a third type of K+ channel beta-subunit which modulates the kinetics of a unique subset of channels in the Kv1 subfamily.
Majumder
K
K
Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030.
De Biasi
M
M
Wang
Z
Z
Wible
B A
BA
D000595:Amino Acid Sequence; D000818:Animals; D016275:Atrial Function; D001483:Base Sequence; D003001:Cloning, Molecular; D006801:Humans; D015640:Ion Channel Gating / Q000235:genetics*; D008564:Membrane Potentials; D008969:Molecular Sequence Data; D009865:Oocytes; D015221:Potassium Channels / Q000096:biosynthesis / Q000235:genetics* / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014981:Xenopus
D015221:Potassium Channels; D012333:RNA, Messenger