Use of Cloned Epstein-Barr Virus DNA to Identify Genes that Determine the Fate of Viral Infection

Summary

Transcription of the Epstein-Barr virus (EBV) genome during different cell-virus interactions was analyzed to identify the loci containing genes which may be responsible for determining the fate of an EBV infection. Transcriptionally active regions of the genome were detected by hybridization of ³²P-labeled cDNA (reverse-transcribed from infected-cell RNA) to the different cloned Bam Hl restriction endonuclease fragments of EBV DNA. Analysis of the transcription in restringently infected cells indicated that, in the absence of complete virus replication, transcription of the viral genome is limited to the W-Y-H region of the Bam Hl restriction map. During permissive or productive infection, transcription of approximately 90% of the viral DNA was detected. Analysis of the immediate-early transcription and transcription kinetics during permissive infection indicated that the Bam H1 M region is transcribed first following the onset of productive replication. Transcription of this region was not detected in restringently infected cells or during primary infection of adult human B lymphocytes. This suggests that expression of a gene(s) within the Bam Hl M region is required to initiate the productive cycle of virus replication. Suppression of this gene may therefore be a prerequisite to immortalization of B lymphocytes by EBV.