A novel pathway for the formation of phosphatidylinositol 3,4-bisphosphate. Phosphorylation of phosphatidylinositol 3-monophosphate by phosphatidylinositol-3-monophosphate 4-kinase

Journal Article · Tue Dec 25 04:00:00 EST 1990 · Journal of Biological Chemistry; (USA)

OSTI ID:6213494

Yamamoto, K; Graziani, A; Carpenter, C; Cantley, L C; Lapetina, E G ^[1]

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1. Burroughs Wellcome Co., Research Triangle Park, NC (USA)

Three polyphosphoinositides containing phosphate at the D-3 position of the inositol ring can be generated in vitro by phosphorylation of phosphatidylinositol, phosphatidylinositol 4-phosphate, and phosphatidylinositol 4,5-bisphosphate by a phosphatidylinositol-3-kinase. An alternative pathway for in vivo synthesis of one of these lipids was recently suggested: phosphatidylinositol 3,4-bisphosphate could be produced by phosphorylation of phosphatidylinositol 3-phosphate at the D-4 position of the inositol ring. Here we demonstrate the presence of an enzyme in human platelets that phosphorylates (32P)phosphatidylinositol 3-phosphate to produce (32P)phosphatidylinositol 3,4-bisphosphate. This enzyme is Mg2(+)-dependent and its apparent molecular mass is approximately 150 kDa as estimated by sucrose gradient centrifugation and gel filtration chromatography. Unlike the major phosphatidylinositol-4-kinase in platelets that is stimulated by the detergent Nonidet P-40, the phosphatidylinositol-3-phosphate-4-kinase is inhibited by Nonidet P-40. Both activities are also differentiated by the action of adenosine. The discovery of this new enzyme raises the possibility that multiple pathways exists for generating D-3 phosphorylated phosphoinositides.

• OSTI ID: 6213494
• Journal Information: Journal of Biological Chemistry; (USA), Journal Name: Journal of Biological Chemistry; (USA) Vol. 265:36; ISSN JBCHA; ISSN 0021-9258
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADENOSINE
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BIOLOGICAL PATHWAYS
BLOOD
BLOOD CELLS
BLOOD PLATELETS
BODY FLUIDS
CHEMICAL REACTIONS
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
ENZYME ACTIVITY
ENZYMES
ESTERS
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
LIPIDS
LIQUID COLUMN CHROMATOGRAPHY
MAMMALS
MAN
MATERIALS
METABOLISM
NUCLEI
NUCLEOSIDES
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOLIPIDS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHORYLATION
PHOSPHOTRANSFERASES
PRIMATES
RADIOISOTOPES
RIBOSIDES
SEPARATION PROCESSES
TRACER TECHNIQUES
TRANSFERASES
VERTEBRATES