Expression cloning of KCRF, a potassium channel regulatory factor.
By functional coexpression screening of a rat cDNA library in Xenopus oocytes, we have cloned a protein (KCRF: K Channel Regulatory Factor) that reduces currents of several K(+) channels: G protein-activated GIRK1/4 (K(ir)3.1/K(ir)3.4), inward rectifier IRK1 (K(ir)2.1), and voltage-dependent K(V)1.1/K(V)beta1.1. KCRF did not modulate two other K(+) channels: ROMK1 (K(ir)1.1) and GIRK1/2 (K(ir)3.1/K(ir)3.2) and the voltage-dependent L-type Ca(2+) channels. Western blot analysis showed that KCRF is ubiquitous in rat tissues. Biochemical and electrophysiological experiments revealed that coexpression of KCRF causes a decrease in the level of expression of IRK1 and K(V)1.1/K(V)beta1.1 proteins in the oocytes.
Department of Physiology and Pharmacology, Sackler School of Medicine, Ramat Aviv, 69978, Israel.
T
T
Keren-Raifman
T
T
Ivanina
Y
Y
Bismuth
N
N
Dascal
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D005260:Female; D015640:Ion Channel Gating / Q000235:genetics; D008969:Molecular Sequence Data; D009865:Oocytes; D015221:Potassium Channels / Q000378:metabolism*; D011506:Proteins / Q000235:genetics* / Q000378:metabolism*; D012326:RNA Splicing; D016601:RNA-Binding Proteins; D051381:Rats; D014981:Xenopus
D015221:Potassium Channels; D011506:Proteins; C413048:Prpf18 protein, rat; D016601:RNA-Binding Proteins