title: The Epstein-Barr virus open reading frame BDLF3 codes for a 100-150 kDa glycoprotein.
abstract: The Epstein-Barr virus (EBV) open reading frame BDLF3 is predicted to code for a glycoprotein on the basis that it contains sequences with signal peptide and transdomain characteristics and nine potential N-linked glycosylation sites. No sequential or positional homologues of BDLF3 have been located in other herpesviruses. A bacterial glutathione S-transferase (GST)-BDLF3 fusion protein was used to demonstrate that over one-third of EBV-immune human sera tested recognized the fusion protein but not GST alone on Western blots. The fusion protein was used to raise polyclonal sera in rabbits. A BDLF3 recombinant baculovirus was constructed using the full-length BDLF3 sequence (AcBDLF3). Rabbit anti-fusion protein sera and some human EBV-immune sera recognized products of approximately 30 and 55 kDa from AcBDLF3-infected insect cells by Western blotting. A peptide representing the carboxy-terminal amino acids 215-234 of the BDLF3 sequence was used to raise anti-peptide sera in rabbits. Anti-peptide serum detected a product by indirect immunofluorescence in acetone-fixed EBV-infected B cells from all cell lines tested. A diffuse band with a molecular mass of 100-150 kDa was detected by Western blot in B95-8 cell lysates, partially purified B95-8 virus and B95-8-infected cell membranes after probing with anti-BDLF3 peptide serum. This product was shown to be glycosylated after enzymatic deglycosylation of a B95-8 virus preparation using neuraminidase, O-glycosidase or N-glycosidase F. The BDLF3 protein products have no known function.
authors.affiliation: Department of Pathology and Microbiology, University of Bristol, School of Medical Sciences, UK.
authors.forename: L A
authors.initials: LA
authors.lastname: Nolan
authors.forename: A J
authors.initials: AJ
authors.lastname: Morgan
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001483:Base Sequence; D015153:Blotting, Western; D002460:Cell Line; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D004854:Herpesvirus 4, Human / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis; D011817:Rabbits / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000276:immunology; D018411:Spodoptera; D014158:Transcription, Genetic; D014162:Transfection
chemical_list: D000914:Antibodies, Viral; D017931:DNA Primers; D006023:Glycoproteins; D011993:Recombinant Fusion Proteins