EBV membrane receptor (CR2) is phosphorylated by protein kinase C (PKC) in the early stages of virus entry into lymphoblastoid cells line (Raji).
Labeling the EBV membrane with octadecylrhodamine-b-chloride (R18) we were able to monitor spectrofluorometrically the early events of EBV fusion, under conditions in which we could affect PKC activity. Binding of EBV to Raji cells induces PKC translocation from the cytosol to the plasma membrane and 32P incorporation into its cellular receptor CR2. CR2 phosphorylation is completely inhibited when cells are preincubated with the PKC inhibitor calphostin c. This treatment also generates a strong inhibition of EBV fusion. Taken together this result suggests a key role of CR2 phosphorylation in the EBV entry into Raji cells.
Aquino
A
A
Dipartimento di Medicina Sperimentale Scienze Biochimiche, University Tor Vergata, Rome, Italy.
Lisi
A
A
Pozzi
D
D
Ravagnan
G
G
Grimaldi
S
S
D000255:Adenosine Triphosphate / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D005456:Fluorescent Dyes; D004854:Herpesvirus 4, Human / Q000502:physiology*; D006801:Humans; D015759:Ionomycin / Q000494:pharmacology; D007700:Kinetics; D008223:Lymphoma; D008561:Membrane Fusion / Q000187:drug effects; D009281:Naphthalenes; D010710:Phosphates / Q000378:metabolism; D010761:Phosphorus Radioisotopes; D010766:Phosphorylation; D011083:Polycyclic Compounds / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D017464:Receptors, Complement 3d; D011991:Receptors, Virus / Q000187:drug effects / Q000378:metabolism*; D012235:Rhodamines; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D005456:Fluorescent Dyes; D009281:Naphthalenes; D010710:Phosphates; D010761:Phosphorus Radioisotopes; D011083:Polycyclic Compounds; D017464:Receptors, Complement 3d; D011991:Receptors, Virus; D012235:Rhodamines; D015759:Ionomycin; D000255:Adenosine Triphosphate; D011493:Protein Kinase C; C058819:calphostin C; D013755:Tetradecanoylphorbol Acetate; C044542:octadecyl Rhodamine B chloride