The Regulated Expression of Epstein--Barr Virus. III. Proteins Specified by EBV During the Lytic Cycle

Abstract

SUMMARYThe experiments show that 30 virus-induced or virus-specified proteins were synthesized in Raft ceils after superinfection with Epstein-Barr virus (EBV) derived from P3HR1 cells. Using a combination of pulse labelling, application of cycloheximide blocks at different times post-infection, treatment with amino acid analogues and inhibition of DNA synthesis it was shown that three groups of proteins appear in Raji cells after superinfection; the synthesis of the proteins in any one group appears to be coordinately regulated. Amongst the six virus-induced proteins which were synthesized immediately after release from an early cycloheximide block one would expect to find those proteins essential for the transition from EBNA to EA synthesis. Using human sera with differing specificities for the various antigen groups 11 proteins were identified as being specifically precipitated by sera having high titres against the EBV-induced early antigen complex.

Hepatitis B virus surface antigen as a reporter of promoter activity

“…For the induction of the lytic cycle Raji cells were either induced chemically or superinfected with P3HR-1 virus (Bayliss and Wolf, 1981). Chemical induction was achieved by addition of 40 mM TPA and 3 mM * Na-butyrate to the culture medium after transfection.…”

“…(Schwarzmann et al, 1988;Leser et al, 1989), and translation and protein modification (Bayliss and Wolf, 1981;MarschalI et al, 1989). We developed a sensitive method to detect low-grade changes of gene activation on the promoter level.…”

An immunoprecipitation blocking assay for the analysis of EBV induced antigens

“…The beads were then collected by centrifugation, and 100 ~1 of an extract of superinfected Raji cells labelled with [35S] methionine (Bayliss and Wolf, 1981) were added to the antibody coated beads. The mixture was further shaken for 2 h. The beads were collected by centrifugation, washed 3 times in IP buffer and twice in distilled water.…”

“…When Raji cells are superinfected at high multiplicities with EBV derived from P3HRl cells they synthesize a large number of EBV specified proteins (Bayliss and Nonoyama, 1978, Wolf and Bayliss, 1978, Bayliss and Wolf, 1981. The success or failure to achieve a good superinfection is highly dependent upon the quality of both the virus concentrates and the target cells.…”

Expression of the Epstein-Barr virus 138-kDa early protein in Escherichia coli for the use as antigen in diagnostic tests

“…after induction of EBV-infected cells the ep138 is one of the most abundant early proteins (Bayliss and Wolf, 1981); sera from different NPC-patients contain antibodies against this protein (Wolf et al, 1984); the coding region was located in the BamHI-A fragment in an area with appropriate reading frames (Seibl and Wolf, 1985). Yanisch-Perron, et al, 1985) and plasmids pUC8, pUC9, pUC13 (Vieira and Messing, 1982), pEA305 (Amann et al, 1983), pKK240-11 (Amann and Brosius, 1985), pUR278, pUR288 (RUther and MUller-Hill, 1983) and pINIIIAl (Masui et al, 1984) were used.…”