CST (BART BARF0) family viral RNAs are expressed in several types of Epstein-Barr virus (EBV) infection, including EBV-associated cancers.Many different spliced forms of these RNAs have been described; here we have clarified the structures of some of the more abundant splicing patterns. We report the first cDNAs representing a full-length CST mRNA from a clone library and further characterize the transcription start. The relative abundance of splicing patterns and genomic analysis of the open reading frames (ORFs) suggest that, in addition to the much studied BARF0 ORF, there may be important products made from some of the upstream ORFs in the CST RNAs. Potential biological functions are identified for two of these. The product of the RPMS1 ORF is shown to be a nuclear protein that can bind to the CBF1 component of Notch signal transduction. RPMS1 can inhibit the transcription activation induced through CBF1 by NotchIC or EBNA-2. The protein product of another CST ORF, A73, is shown to be a cytoplasmic protein which can interact with the cell RACK1 protein. Since RACK1 modulates signaling from protein kinase C and Src tyrosine kinases, the results suggest a possible role for CST products in growth control, perhaps consistent with the abundant transcription of CST RNAs in cancers such as nasopharyngeal carcinoma.In several types of infection, in addition to the well-established EBNA, LMP and EBER genes, Epstein-Barr virus (EBV) has been found to express various spliced RNAs transcribed rightward from the region spanning 150,000 to 161,000 on the B95-8 EBV genetic map. These have been referred to as complementary strand transcripts (CSTs), BamHI A rightward transcripts (BARTs), or the BARF0 RNAs. RNAs of this type were originally identified in cDNA made from the C15 xenograft culture of nasopharyngeal carcinoma (NPC) tissue (17). Similar RNAs were subsequently found in various EBV-positive NPC tumor biopsies and xenografts, Burkitt's lymphoma, lymphoid cell lines (LCLs) (3,6,11,15,19,31,43), and biopsies of oral hairy leukoplakia (24). Expression of CST RNAs has also been demonstrated in peripheral blood of normal human carriers of EBV (5), sera from NPC patients have been found to immunoprecipitate a protein product of the BARF0 open reading frame (ORF) made in vitro (12), and cytotoxic T lymphocytes that respond to a peptide derived from BARF0 have been identified in EBV-infected people (22).A very complicated picture of alternatively spliced CST RNAs has built up (36, 38), but some of the proposed structures have been deduced using very sensitive reverse transcription (RT)-PCR methods or have been only single isolates from cDNA libraries, and thus they may yet represent very minor species within the family of RNAs that can be expressed. Predominant sizes of the RNAs expressed have been deduced from Northern blots, but these have only partly been related to the spliced RNA structures. In addition, the coding content of the CST RNAs remains uncertain. Most attention has focused on the BARF0 ORF, particularly a sp...

Doxorubicin (DOX), a commonly used antitumor agent, is often accompanied by its dosage-dependent cardiotoxicity, which incorporates ferroptosis in its pathogenesis. Protein arginine methyltransferase 4 (PRMT4) is a transcription regulator involved in the modulation of oxidative stress and autophagy, but its role in DOX-induced cardiomyopathy (DIC) and ferroptosis remains elusive. Herein, we aimed to investigate the involvement and the underlying mechanisms of PRMT4 in the pathogenesis of DIC. Our present study revealed that the expression level of PRMT4 was markedly decreased in DOX-treated cardiomyocytes. Interestingly, it is noted that PRMT4 overexpression accelerated ferroptosis to aggravate DIC, while its gene disruption or pharmaceutical inhibition exhibited the opposite effect. Mechanistically, our observation demonstrated that PRMT4 interacted with the nuclear factor erythroid 2-related factor 2 (Nrf2) to promote its enzymatic methylation, which restricted the nuclear translocation of Nrf2 and subsequently suppressed the transcription of glutathione peroxidase 4 (GPX4). Importantly, the detrimental role of PRMT4 in DOXinduced cardiomyocyte ferroptosis was abolished by Nrf2 activation or Fer-1 administration. Collectively, our data reveal that PRMT4 inhibits Nrf2/GPX4 signaling to accelerate ferroptosis in DIC, suggesting that targeting PRMT4 may present as a potential preventive strategy against the development of DIC.

In Epstein-Barr virus (EBV)-associated tumors in nonimmunocompromised patients, EBV gene expression is highly restricted. EBV-encoded nuclear antigen (EBNA)-1 is expressed, whereas the immunogenic and proliferative EBNAs are not. This pattern of EBNA expression is generated by usage of the BamHI-Q promoter (Qp). We have determined that the JAK/STAT pathway positively regulates Qp activity. Epstein-Barr virus (EBV) is a ubiquitous herpesvirus that is carried by the majority of the population as a latent, persistent infection. Primary exposure to EBV may result in infectious mononucleosis, and EBV is also associated with both B cell and epithelial malignancies (1). Different forms of EBV latency are recognized, and these are defined by the extent of latent viral gene expression (2). During primary exposure, EBV infection of B cells gives rise to a population of cells that express the full spectrum of EBV-encoded nuclear antigens (EBNAs) and latency membrane proteins (LMPs) as well as the BamHI-A rightward transcripts and the polymerase III transcribed, noncoding EBERs. This expression pattern, which has been termed latency III (3), is also seen in lymphoblastoid cell lines in culture. Among the genes expressed in latency III are those for the growth-proliferative and highly immunogenic EBNA-2-and EBNA-3-family proteins (4). The question of how a lifelong latent infection could persist in the face of an active cytotoxic T cell response has recently been clarified by the recognition that in vivo latency in healthy EBVseropositive individuals takes place in resting B cells with a memory B cell phenotype (5, 6). In these cells, EBV gene expression is extremely limited. The only viral transcripts consistently detected are those for LMP-2A and the BamHI-A rightward transcripts (7-9). EBV-associated tumors demonstrate a third pattern of latency-gene expression (latency I/II) in which only EBNA-1 and the BamHI-A rightward transcripts are expressed (latency I) or there is variable expression of the latency membrane proteins LMP-1, LMP-2A, and LMP-2B in additon to EBNA-1 and the BamHI-A rightward transcripts (latency II) (1).

Background and purposeStroke is the second leading cause of death worldwide and the leading cause of mortality and long-term disability in China, but its underlying risk genes and pathways are far from being comprehensively understood. We here describe the design and methods of whole genome sequencing (WGS) for 10 914 patients with acute ischaemic stroke or transient ischaemic attack from the Third China National Stroke Registry (CNSR-III).MethodsBaseline clinical characteristics of the included patients in this study were reported. DNA was extracted from white blood cells of participants. Libraries are constructed using qualified DNA, and WGS is conducted on BGISEQ-500 platform. The average depth is intended to be greater than 30× for each subject. Afterwards, Sentieon software is applied to process the sequencing data under the Genome Analysis Toolkit best practice guidance to call genotypes of single nucleotide variants (SNVs) and insertion-deletions. For each included subject, 21 fingerprint SNVs are genotyped by MassARRAY assays to verify that DNA sample and sequencing data originate from the same individual. The copy number variations and structural variations are also called for each patient. All of the genetic variants are annotated and predicted by bioinformatics software or by reviewing public databases.ResultsThe average age of the included 10 914 patients was 62.2±11.3 years, and 31.4% patients were women. Most of the baseline clinical characteristics of the 10 914 and the excluded patients were balanced.ConclusionsThe WGS data together with abundant clinical and imaging data of CNSR-III could provide opportunity to elucidate the molecular mechanisms and discover novel therapeutic targets for stroke.