Regulated expression of K+ channel genes in electrically silent mammalian cells by linkage to beta-globin gene-activation elements.
Fundamental studies of the mechanism of human beta-like globin gene-expression have identified DNA sequences (locus control regions or LCRs) which directly influence the specific activation of beta-globin genes in erythroid cells. Here we report the first applications of LCR-mediated gene-activation to stable electrophysiological expression of several homomultimeric ion channel proteins. We describe expression driven from a native K+ channel gene promoter region, contiguous to an intronless coding sequence, within a single excised human genomic DNA fragment. In addition, cDNAs encoding both inactivating and non-inactivating mammalian K+ currents have been expressed by insertion between the promoter and second intron of the human beta-globin gene. Expression levels are characteristically independent of integration position and are proportional to LCR-gene copy number, a parameter specific for each clonal cell line. K+ channel expression is inducible by erythroid differentiation and has been demonstrated by electrophysiological recordings of cells taken directly from culture.
Shelton
P A
PA
ICI-University Joint Laboratory, University of Leicester, U.K.
Davies
N W
NW
Antoniou
M
M
Grosveld
F
F
Needham
M
M
Hollis
M
M
Brammar
W J
WJ
Conley
E C
EC
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D018076:DNA, Complementary / Q000235:genetics; D004594:Electrophysiology; D015672:Erythroid Precursor Cells / Q000378:metabolism; D005786:Gene Expression Regulation; D008040:Genetic Linkage; D005914:Globins / Q000235:genetics*; D006801:Humans; D008564:Membrane Potentials; D051379:Mice; D008957:Models, Genetic; D008969:Molecular Sequence Data; D015221:Potassium Channels / Q000235:genetics*; D015533:Transcriptional Activation
D018076:DNA, Complementary; D015221:Potassium Channels; D005914:Globins