Exposure of susceptible neuroblastoma N2a cells to mouse scrapie prions leads to infection, as evidenced by the continued presence of the scrapie form of the prion protein (PrP(Sc)) and infectivity after 300 or more cell doublings. We find that exposure to phosphatidylinositol-specific phospholipase C (PIPLC) or to the monoclonal anti-prion protein (PrP) antibody 6H4 not only prevents infection...

Characterization of the Involvement of Integrins, Focal Adhesion Kinase, and Phospholipase C Enzymes Endogenous to the Oocyte in Bovine Fertilization and Oocyte Activation

Chemoattractants, including chemokines, play a central role in regulation of inflammatory reactions by attracting and activating leukocytes. These molecules have been found to regulate metabolism of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P(2)) via phospholipase C (PLC) and phosphoinositide 3-kinase (PI3K). Recent studies of mouse lines that lack PLC-(beta)2, PLC-(beta)3, or PI3K(gamm...

An extracellular phospholipase C was partially purified from Pseudomonas sp. strain KS3.2. The enzyme was composed of an approximately 18-kDa peptide. Maximal enzyme activity was found at pH 7.2 and 50 degrees C. The enzyme retained activity between pH 8 and 9, and 50% activity at about 52 degrees C for 30 min. The enzyme sample showed the highest activity on phosphatidylcholine and low activit...

We have examined the effects of phospholipase C pretreatment on Ca2+ transport in highly purified canine cardiac sarcolemmal vesicles. Na+-Ca2+ exchange, measured as Nai+-dependent Caz+ uptake, is stimulated when 10-70% of the membrane phospholipid has been hydrolyzed. Although the phospholipase C treatment also increases sarcolemmal passive Ca2+ flux, the membrane maintains a sufficient permea...

Phospholipase C-gamma1, a tyrosine kinase substrate, hydrolyses phosphatidylinositol 4,5-bisphosphate to produce inositol 1,4,5-trisphosphate and diacylglycerol, which act as second messenger moleculesto mobilize intracellular calcium and activate protein kinase C, respectively. We have investigated the role of phospholipase C-gamma1 in anoikis, or cell death, induced by the loss of extracellul...

Ca(2+) enters cells through an assortment of Ca(2+)-permeable channels that respond to different stimuli and couple to different cellular responses. Several different Ca(2+) entry pathways can be activated by receptors that stimulate phospholipase C (PLC). Both limbs of this signaling pathway (IP(3) and diacylglycerol), PLC itself, and its substrate (PIP(2)) contribute to the coordinate regulat...

Ca2+-mobilizing agonists, including hormones, neurotransmitters and growth factors, cause profound changes in cellular lipid metabolism. These changes are initiated by receptormediated activation of various phospholipases including phospholipase A2, phospholipase C and phospholipase D. Phospholipase A2 hydrolyses several phospholipids including phosphatidylinositol, phosphatidylcholine (PtdCho)...

BACKGROUND AND PURPOSE The hypothesis of calcium-induced neuronal damage has been proposed regarding brain ischemia. Phospholipase C is an enzyme that catalyzes the phosphodiesteratic cleavage of phosphatidylinositol. The cleavage of phosphatidylinositol 4,5-bisphosphate by phospholipase C yields 1,4,5-inositol triphosphate, which mediates intracellular release of calcium, and 1,2-diacylglycero...