Requirement for phosphatidylinositol transfer protein in epidermal growth factor signaling.
Stimulation of phosphatidylinositol-4,5-bisphosphate (PIP2) hydrolysis is a widespread mechanism for receptor-mediated signaling in eukaryotes. Cytosolic phosphatidylinositol transfer protein (PITP) is necessary for guanosine triphosphate (GTP)-dependent hydrolysis of PIP2 by phospholipase C-beta (PLC-beta), but the role of PITP is unclear. Stimulation of phospholipase C-gamma (PLC-gamma) in A431 human epidermoid carcinoma cells treated with epidermal growth factor (EGF) required PITP. Stimulation of PI-4 kinase in cells treated with EGF also required PITP. Coprecipitation studies revealed an EGF-dependent association of PITP with the EGF receptor, with PI-4 kinase, and with PLC-gamma.
Kauffmann-Zeh
A
A
Protein Biochemistry Group, Ludwig Institute for Cancer Research, University College London School of Medicine, UK.
Thomas
G M
GM
Ball
A
A
Prosser
S
S
Cunningham
E
E
Cockcroft
S
S
Hsuan
J J
JJ
D019870:1-Phosphatidylinositol 4-Kinase; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism / Q000502:physiology*; D003600:Cytosol / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000378:metabolism / Q000502:physiology*; D066246:ErbB Receptors / Q000378:metabolism; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism / Q000502:physiology; D008565:Membrane Proteins; D010716:Phosphatidylinositols / Q000378:metabolism; D051966:Phospholipase C gamma; D049294:Phospholipid Transfer Proteins; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism; D011485:Protein Binding; D051381:Rats; D015398:Signal Transduction / Q000502:physiology*; D014407:Tumor Cells, Cultured; D010738:Type C Phospholipases / Q000378:metabolism / Q000502:physiology
D002352:Carrier Proteins; D007527:Isoenzymes; D008565:Membrane Proteins; D010716:Phosphatidylinositols; D049294:Phospholipid Transfer Proteins; D004815:Epidermal Growth Factor; D017853:Phosphotransferases (Alcohol Group Acceptor); D019870:1-Phosphatidylinositol 4-Kinase; D066246:ErbB Receptors; D010738:Type C Phospholipases; D051966:Phospholipase C gamma