Identification of glycyrrhizin-binding protein kinase as casein kinase II and characterization of its associated phosphate acceptors in mouse liver.
Two forms (G-I and G-II kinases) of casein kinase II(CK-II) in a partially purified CK-II fraction (Mono Q fraction) of mouse liver were separated by means of glycyrrhizin (GL)-affinity column chromatography. Biochemical characterization revealed that these two GL-binding kinases were identical to CK-II. Two phosphate acceptors [p99 (pI 7.0) and p56] copurified with CK-II were identified as ERp99 (Hsp-90-family protein) and calreticulin, respectively. Another protein [p100 (pI 9.0)], which crossreacted with anti-serum against human glucocorticoid receptor (GR), was associated with ERp99. Phosphorylation of p99 [a hetero-complex of p99 (pI 7.0) and p100 (pI 9.0)] and p56 by CK-II in vitro was stimulated significantly by low levels (1-3 microM) of GL, but inhibited significantly at doses above 20 microM. However, no effect of GL on autophosphorylation of ERp99 was detected. The data provided here suggest that GL can regulate CK-II-mediated phosphorylation involved in the GL-induced biological effects in mammalian cells.
Harada
S
S
Laboratory of Genetical Biochemistry, Kitasato University, School of Allied Health Sciences, Sagamihara, Japan.
Karino
A
A
Shimoyama
Y
Y
Shamsa
F
F
Ohtsuki
K
K
D000818:Animals; D047390:Casein Kinase II; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D006034:Glycyrrhetinic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D019695:Glycyrrhizic Acid; D008099:Liver / Q000378:metabolism*; D051379:Mice; D010710:Phosphates / Q000378:metabolism*; D010766:Phosphorylation; D011233:Precipitin Tests; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000302:isolation & purification* / Q000378:metabolism
D010710:Phosphates; D019695:Glycyrrhizic Acid; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases; D006034:Glycyrrhetinic Acid