Post-translational modifications of Epstein Barr virus BARF1 oncogene-encoded polypeptide.
Epstein-Barr virus is associated with several human lymphomas and carcinomas, and its BARF1 oncogene encodes a protein that is thought to play an important role in carcinogenesis. A BARF1 recombinant adenovirus expression system, which led us to discover the macromolecular size of the cleaved and secreted form of the BARF1 protein in the native state and its mitogenic capacity on various cell lines in culture, was used further to investigate the structure and maturation of the BARF1 protein. We recently reported biophysical studies that showed dimer-based oligomerization of the BARF1 polypeptide. Here, new data are presented that confirm post-translational modifications predicted from the BARF1 sequence: phosphorylation on serine and threonine, and N- and O-glycosylation. The N- and O-glycans were partially characterized and it was demonstrated that both modifications are required for active secretion of the BARF1 protein via the classical pathway.
de Turenne-Tessier
Mireille
M
Virologie et Pathologie Humaine, CNRS FRE3011, Université Lyon 1, Faculté de Médecine RTH Laennec, rue G. Paradin, F-69372 Lyon, France.
Ooka
Tadamasa
T
Virologie et Pathologie Humaine, CNRS FRE3011, Université Lyon 1, Faculté de Médecine RTH Laennec, rue G. Paradin, F-69372 Lyon, France.
D015180:Electrophoresis, Gel, Two-Dimensional; D006031:Glycosylation; D006367:HeLa Cells; D004854:Herpesvirus 4, Human / Q000235:genetics*; D006801:Humans; D009857:Oncogenes; D011134:Polysaccharides / Q000032:analysis; D011499:Protein Processing, Post-Translational; D014764:Viral Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism
C086495:BARF1 protein, Human herpesvirus 4; D011134:Polysaccharides; D014764:Viral Proteins