[16] Phospholipase C activity in Dictyostelium discoideum using endogenous nonradioactive phosphatidylinositol 4,5-bisphosphate as substrate

Loss of a prolyl oligopeptidase confers resistance to lithium by elevation of inositol (1,4,5) trisphosphate

“…Pellets were washed and resuspended in equal volumes of buffer A. Bradford assays confirmed equal protein levels in extracts. PLC and IP 5 dephosphorylation were measured by the production of IP 3 from pellet fractions at 22°C in the presence of 10 mM CaCl 2 and inhibitors of IP 3 breakdown, 25 mM LiCl and 250 μM diphosphoglycerate (Bominaar and Van Haastert, 1994; Van Dijken et al ., 1997). IP 5 (100 μM) (Sigma Chemical Co.) was added for the measurement of the conversion of IP 5 to IP 3 .…”

“…To determine the cause of the increased IP 3 concentration in the dpoA mutant, we examined synthesis and degradation of IP 3 . The breakdown of PIP 2 to IP 3 was examined in membrane fractions prepared from wild-type and dpoA mutant cells by the method described by Bominaar and Van Haastert (1994). This method assays the breakdown of endogenous PIP 2 by PLC and hence would be sensitive to changes in both PLC activity and PIP 2 concentration.…”

Mechanism of action of the nonlipophilic antiallergic drug eclazolast (REV 2871) in the inhibition of mediator release in a mast cell model

“…Effect of the drugs on the level of IP 3 was measured as presented previously [12], and was based on the method of Bominaar and Van Haastert [13].…”