A fifth Epstein-Barr virus nuclear protein (EBNA3C) is expressed in latently infected growth-transformed lymphocytes.
Three distantly homologous neighboring long open reading frames in the Epstein-Barr virus (EBV) genome are preceded by short open reading frames. The leftmost short and long open reading frames encode EBNA3, a nuclear protein which is slightly smaller (145 kilodaltons [kDa]) than two other nuclear proteins (150 to 155 kDa) detected in Western blots (immunoblots) of latently infected cell protein (K. Hennessy, F. Wang, E. Woodland-Bushman, and E. Kieff, Proc. Natl. Acad. Sci. USA 83:5693-5697, 1986; I. Joab, D. T. Rowe, M. Bodescot, J.-C. Nicolas, P. J. Farrell, and M. Perricaudet, J. Virol. 61:3340-3344, 1987). We have demonstrated that the most rightward short (BERF3) and long (BERF4) open reading frames are spliced in frame at the 3' end of a 5-kilobase latently infected cell RNA and that this RNA begins within or upstream of the EBV long internal repeat. EBV-immune human antibodies specific for the long open reading frame translation product identified a 155-kDa protein on Western blots of latently infected cell protein and specifically reacted with large nonnucleolar nuclear granules in every latently infected cell. Expression of the cDNA in BALB/c 3T3 cells resulted in translation of full-size EBNA3C but had no effect on cell morphology, contact inhibition, or serum independence.
Petti
L
L
Kovler Viral Oncology Laboratory, University of Chicago, Illinois 60637.
Sample
J
J
Wang
F
F
Kieff
E
E
D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D000918:Antibody Specificity; D000956:Antigens, Viral / Q000235:genetics*; D002460:Cell Line; D002846:Chromatography, Affinity; D004279:DNA, Viral / Q000235:genetics; D019309:Epstein-Barr Virus Nuclear Antigens; D005091:Exons; D005455:Fluorescent Antibody Technique; D005814:Genes, Viral; D004854:Herpesvirus 4, Human / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007118:Immunoassay; D008214:Lymphocytes / Q000382:microbiology*; D009687:Nuclear Proteins / Q000235:genetics* / Q000276:immunology
D000914:Antibodies, Viral; D000956:Antigens, Viral; D004279:DNA, Viral; D019309:Epstein-Barr Virus Nuclear Antigens; D007106:Immune Sera; D009687:Nuclear Proteins