Cytosolic localization of beta 3-subunit of heterotrimeric GTP binding protein in rat hearts.
The expression of three different subtypes of GTP binding protein beta-subunits (beta 1, beta 2 and beta 3) was examined in rat hearts at both mRNA and protein levels. Among three subtypes, beta 3 mRNA was more abundant in ventricles while beta 1 and beta 2 mRNAs were expressed ubiquitously among ventricles, atria and aortas. The immunodetectable beta 1- and beta 3-proteins were predominantly found in the cytosolic fraction of rat ventricles. In this study, we demonstrate ventricle-specific expression of beta 3-subunit and localization of G protein beta 3-subunit in the cytosol of rat hearts. This unusual cytosolic localization of G protein beta 3-subunit might indicate subtype-specific function of G protein beta (gamma)-subunits in rat hearts.
Muramoto
S
S
Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Sapporo, Japan.
Murakami
T
T
Urasawa
K
K
Kawaguchi
H
H
Kitabatake
A
A
D000818:Animals; D001011:Aorta / Q000378:metabolism; D015152:Blotting, Northern; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D002417:Cattle; D003600:Cytosol / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000032:analysis / Q000096:biosynthesis*; D015870:Gene Expression; D006325:Heart Atria; D006352:Heart Ventricles; D046911:Macromolecular Substances; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D011921:Rats, Inbred WKY; D012160:Retina / Q000378:metabolism
D046911:Macromolecular Substances; D012333:RNA, Messenger; D019204:GTP-Binding Proteins