TY - JOUR
T1 - Characterization of gene organization and generation of heterogeneous mRNA species of rat ISK protein
AU - Iwai, Masazumi
AU - Masu, Masayuki
AU - Tsuchida, Kunihiro
AU - Mori, Takahide
AU - Ohkubo, Hiroaki
AU - Nakanishi, Shigetada
PY - 1990/8
Y1 - 1990/8
N2 - The ISK protein is a novel, probably epithelial potassium channel which differs from conventional potassium channels in its structure, electrophysiology, and tissue distribu tion. In this investigation, we isolated and analyzed genomic and cDNA clones coding for the rat ISK protein to characterize the structural organization and expression pattern of the ISK protein gene. This analysis, together with primer extension and RNase protection experiments, indicated that the ISK protein mRNA is initiated from two different upstream exons and then encoded by an uninterrupted downstream exon covering the protein-coding and the 3′-untranslated regions of the mRNA. RNA blot hybridization analysis showed additional generation of several large species of mRNAs which result from Inclusion of a part of the intron sequence and the 3′-flanking region of the ISK protein gene. Thus, the single ISK protein gene is involved in the production of multiple species of mRNAs through a variety of cellular mechanisms including transcription initiation at different sites, alterna tive RNA splicing, and polyadenylation at different sites. The heterogeneity of the ISK protein mRNM may be associated with the emergence of the functional and regulatory diversity observed for potassium ion permeation in epithelial cells.
AB - The ISK protein is a novel, probably epithelial potassium channel which differs from conventional potassium channels in its structure, electrophysiology, and tissue distribu tion. In this investigation, we isolated and analyzed genomic and cDNA clones coding for the rat ISK protein to characterize the structural organization and expression pattern of the ISK protein gene. This analysis, together with primer extension and RNase protection experiments, indicated that the ISK protein mRNA is initiated from two different upstream exons and then encoded by an uninterrupted downstream exon covering the protein-coding and the 3′-untranslated regions of the mRNA. RNA blot hybridization analysis showed additional generation of several large species of mRNAs which result from Inclusion of a part of the intron sequence and the 3′-flanking region of the ISK protein gene. Thus, the single ISK protein gene is involved in the production of multiple species of mRNAs through a variety of cellular mechanisms including transcription initiation at different sites, alterna tive RNA splicing, and polyadenylation at different sites. The heterogeneity of the ISK protein mRNM may be associated with the emergence of the functional and regulatory diversity observed for potassium ion permeation in epithelial cells.
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U2 - 10.1093/oxfordjournals.jbchem.a123181
DO - 10.1093/oxfordjournals.jbchem.a123181
M3 - Article
C2 - 2229022
AN - SCOPUS:0025329834
VL - 108
SP - 200
EP - 206
JO - Journal of Biochemistry
JF - Journal of Biochemistry
SN - 0021-924X
IS - 2
ER -