Novel transcription from the Epstein-Barr virus terminal EcoRI fragment, DIJhet, in a nasopharyngeal carcinoma

Abstract

Transcription of Epstein-Barr virus (EBV) genes in epithelial tissue, one of the two principal cell types infected by EBV, is not well characterized. EBV transcription in a nasopharyngeal carcinoma established in nude mice, C15, has been analyzed by using strand-specific RNA probes and sequence analysis of a C15 cDNA library. In C15, two equally abundant mRNAs of 3.7 and 2.8 kilobases (kb) are encoded by the sequences that encode latent membrane protein (LMP). Hybridization with probes specific for the 3' end of the LMP mRNA to Northern (RNA) blots and sequence analysis of cDNAs representing the messages indicated that the 3.7and 2.8-kb mRNAs are 3' coterminal. Sequence analysis of additional cDNAs revealed an mRNA that is spliced identically to the LMP mRNA but is initiated 5' to the promoter for LMP. A probe representing the sequences contained within the cDNA which are 5' to the LMP promoter identffied the 3.7-kb mRNA in C15 and a low-abundance 3.7-kb mRNA in B95-8 RNA. These data indicate that transcription of the LMP-encoding sequences is complex and that LMP can be expressed from an additional RNA in both nasopharyngeal carcinoma and lymphoid cells. Hybridization with BamHI-A identified a predominant 4.8-kb mRNA and two less abundant larger-molecular-weight mRNAs transcribed in C15. These mRNAs are consistently expressed in all passages in nude mice of the C15 tumor. Hybridization with strand-specific probes and sequence analysis of three cDNAs revealed that these mRNAs are transcribed from left to right. Sequence analysis of cDNAs representing the 3' end of the mRNAs identified an open reading frame that could potentially encode a protein 4948 on July 6, 2020 by guest

Transcriptional expression of Epstein‐Barr virus genes and proto‐oncogenes in North African nasopharyngeal carcinoma

“…tematically in individual cell specimens; however, in view of the complexity of BARFO transcription [Hitt et al, 1989;Gilligan et al, 1990;Chen et al, 1992;Karran et al, 1992;Zhang and Ooka, 19951, further studies using riboprobes are necessaiy to confirm our observations. The transforming early gene BARF1 Lwei and Ooka, 1989;Wei et al, 19941 did not give rise to sufficiently abundant transcripts to be detectable by the 32PP-cDNA method, but weak bands were detected in 2 of 5 biopsies after Northern blotting and detection using a riboprobe.…”

The role of Epstein‐Barr virus–encoded microRNA BART7 status of resection margins in the prediction of local recurrence after salvage nasopharyngectomy for recurrent nasopharyngeal carcinoma

“…12 Furthermore, there is intense production of the rightward transcripts, called BARTs (Bam HI-A rightward transcripts), through the Bam H1A restriction fragment of the EBV genome. 13,14 These appear to be a major source of EBV-encoded microRNAs (miRs) called miR-BARTs. 15,16 Wong et al used high-throughput analysis to demonstrate the up-regulation of multiple EBVencoded miRNAs in NPC.…”

Epstein-Barr virus (EBV)-encodedBARF1 gene is expressed in nasopharyngeal carcinoma and EBV-associated gastric carcinoma tissues in the absence of lytic gene expression

“…The BamHI-A fragment of the EBV genome encodes two different genes, BARTs and BARF1. BARTs is located at 150,000-161,000 bp of B95-8 EBV DNA [Gilligan et al, 1990]. BARTs has several distinctly spliced forms which are 3 0 -end coterminal [Gilligan et al, 1990;Sadler and Raab-Traub, 1995;Zhang et al, 2001].…”

“…BARTs is located at 150,000-161,000 bp of B95-8 EBV DNA [Gilligan et al, 1990]. BARTs has several distinctly spliced forms which are 3 0 -end coterminal [Gilligan et al, 1990;Sadler and Raab-Traub, 1995;Zhang et al, 2001]. The BARF1 gene is located at the downstream of BARTs (at positions 165,449-166,189 bp), encodes 221 amino acids, and is translated into 31-33 kDa proteins [Zhang et al, 1988].…”