TY - JOUR
T1 - Inhibition of CDP-DG:iNositol transferase by inostamycin
AU - Imoto, Masaya
AU - Taniguchi, Yoshiko
AU - Umezawa, Kazuo
PY - 1992/8
Y1 - 1992/8
N2 - Inostamycin, a novel microbial secondary metabolite, inhibited [3H]inositol and 32P1 incorporation into phosphatidylinositol (PtdIns) induced by epidermal growth factor (EGF) in cultured A431 cells, the IC50 being 0.5 μg/ml, without inhibiting macromolecular synthesis. The drug inhibited cellular inositol phosphate formation only when it was added at the same time as labeled inositol. It was found to inhibit in vitro CDP-DG:inositol transferase activity of the A431 cell membrane, the IC50 being about 0.02 μg/ml. It did not inhibit tyrosine kinase, PtdIns phospholipase C, or PtdIns kinase. Therefore, inhibition of PtdIns turnover by inostamycin must be due to the inhibition of CDP-DG:inositol transferase. Thus, inostamycin is a novel inhibitor of CDP-DG:inositol transferase.
AB - Inostamycin, a novel microbial secondary metabolite, inhibited [3H]inositol and 32P1 incorporation into phosphatidylinositol (PtdIns) induced by epidermal growth factor (EGF) in cultured A431 cells, the IC50 being 0.5 μg/ml, without inhibiting macromolecular synthesis. The drug inhibited cellular inositol phosphate formation only when it was added at the same time as labeled inositol. It was found to inhibit in vitro CDP-DG:inositol transferase activity of the A431 cell membrane, the IC50 being about 0.02 μg/ml. It did not inhibit tyrosine kinase, PtdIns phospholipase C, or PtdIns kinase. Therefore, inhibition of PtdIns turnover by inostamycin must be due to the inhibition of CDP-DG:inositol transferase. Thus, inostamycin is a novel inhibitor of CDP-DG:inositol transferase.
UR - http://www.scopus.com/inward/record.url?scp=0026776047&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0026776047&partnerID=8YFLogxK
U2 - 10.1093/oxfordjournals.jbchem.a123894
DO - 10.1093/oxfordjournals.jbchem.a123894
M3 - Article
C2 - 1328172
AN - SCOPUS:0026776047
SN - 0021-924X
VL - 112
SP - 299
EP - 302
JO - Journal of biochemistry
JF - Journal of biochemistry
IS - 2
ER -