Viral reprogramming of host transcription initiation.

Viruses are master remodelers of the host cell environment in support of infection and virus production. For example, viruses typically regulate cell gene expression through modulating canonical cell promoter activity. Here, we show that Epstein Barr virus (EBV) replication causes 'de novo' transcription initiation at 29674 new transcription start sites throughout the cell genome. De novo transcription initiation is facilitated in part by the unique properties of the viral pre-initiation complex (vPIC) that binds a TATT[T/A]AA, TATA box-like sequence and activates transcription with minimal support by additional transcription factors. Other de novo promoters are driven by the viral transcription factors, Zta and Rta and are influenced by directional proximity to existing canonical cell promoters, a configuration that fosters transcription through existing promoters and transcriptional interference. These studies reveal a new way that viruses interact with the host transcriptome to inhibit host gene expression and they shed light on primal features driving eukaryotic promoter function.

Parental protective and risk factors regarding cannabis use in adolescence: A national sample from the Chilean school population.

Background: Research has increased our understanding of the parental factors associated with the initiation and development of cannabis use disorder in adolescents, but few studies about this have been performed in middle- or low-income countries.Objective: First, to examine whether perceived past parental drug use, parental monitoring, and attitude toward adolescent cannabis use are associated with general and problematic cannabis use in Chilean adolescents. Second, to explore whether perceived past parental drug use weakens the associations of protective factors with general and problematic adolescent cannabis use.Methods: Regression analyses were performed on cross-sectional data from a multistage probabilistic sample stratified by clusters (municipalities, school and grade) of 43,060 students (47% male, mean age 15.5 years) from grades 8 to 12, which was collected from the Chilean National School Survey on Drug Use (2013).Results: Perceived past parental drug use increased the likelihood of adolescent cannabis use in general, but not its problematic use. Parental monitoring of adolescents' whereabouts and parental opposition to adolescent cannabis use decreased the likelihood of adolescent cannabis use in general, as well as problematic use. Perceived past parental drug use only interacted with parental monitoring of school activities.Conclusions: In line with research from the United States, the Netherlands and Spain, parental monitoring of adolescents' whereabouts and a strong parental opposition to cannabis use appear to be protective factors, irrespective of past parental use. However, the effectiveness of monitoring adolescents' school activities seems to decrease when parents are perceived as having used drugs in the past.

Circular RNAs add diversity to androgen receptor isoform repertoire in castration-resistant prostate cancer.

Deregulated expression of circular RNAs (circRNAs) is associated with various human diseases, including many types of cancer. Despite their growing links to cancer, there has been limited characterization of circRNAs in metastatic castration-resistant prostate cancer, the major cause of prostate cancer mortality. Here, through the analysis of an exome-capture RNA-seq dataset from 47 metastatic castration-resistant prostate cancer samples and ribodepletion and RNase R RNA-sequencing of patient-derived xenografts (PDXs) and cell models, we identified 13 circRNAs generated from the key prostate cancer driver gene-androgen receptor (AR). We validated and characterized the top four most abundant, clinically relevant AR circRNAs. Expression of these AR circRNAs was upregulated during castration-resistant progression of PDXs. The upregulation was not due to global increase of circRNA formation in these tumors. Instead, the levels of AR circRNAs correlated strongly with that of the linear AR transcripts (both AR and AR variants) in clinical samples and PDXs, indicating a transcriptional mechanism of regulation. In cultured cells, androgen suppressed the expression of these AR circRNAs and the linear AR transcripts, and the suppression was attenuated by an antiandrogen. Using nuclear/cytoplasmic fractionation and RNA in-situ hybridization assays, we demonstrated predominant cytoplasmic localization of these AR circRNAs, indicating likely cytoplasmic functions. Overall, this is the first comprehensive characterization of circRNAs arising from the AR gene. With greater resistance to exoribonuclease compared to the linear AR transcripts and detectability of AR circRNAs in patient plasma, these AR circRNAs may serve as surrogate circulating markers for AR/AR-variant expression and castration-resistant prostate cancer progression.

The Epstein Barr virus circRNAome.

Our appreciation for the extent of Epstein Barr virus (EBV) transcriptome complexity continues to grow through findings of EBV encoded microRNAs, new long non-coding RNAs as well as the more recent discovery of over a hundred new polyadenylated lytic transcripts. Here we report an additional layer to the EBV transcriptome through the identification of a repertoire of latent and lytic viral circular RNAs. Utilizing RNase R-sequencing with cell models representing latency types I, II, and III, we identified EBV encoded circular RNAs expressed from the latency Cp promoter involving backsplicing from the W1 and W2 exons to the C1 exon, from the EBNA BamHI U fragment exon, and from the latency long non-coding RPMS1 locus. In addition, we identified circular RNAs expressed during reactivation including backsplicing from exon 8 to exon 2 of the LMP2 gene and a highly expressed circular RNA derived from intra-exonic backsplicing within the BHLF1 gene. While expression of most of these circular RNAs was found to depend on the EBV transcriptional program utilized and the transcription levels of the associated loci, expression of LMP2 exon 8 to exon 2 circular RNA was found to be cell model specific. Altogether we identified over 30 unique EBV circRNAs candidates and we validated and determined the structural features, expression profiles and nuclear/cytoplasmic distributions of several predominant and notable viral circRNAs. Further, we show that two of the EBV circular RNAs derived from the RPMS1 locus are detected in EBV positive clinical stomach cancer specimens. This study increases the known EBV latency and lytic transcriptome repertoires to include viral circular RNAs and it provides an essential foundation and resource for investigations into the functions and roles of this new class of EBV transcripts in EBV biology and diseases.

Global transcript structure resolution of high gene density genomes through multi-platform data integration.

Annotation of herpesvirus genomes has traditionally been undertaken through the detection of open reading frames and other genomic motifs, supplemented with sequencing of individual cDNAs. Second generation sequencing and high-density microarray studies have revealed vastly greater herpesvirus transcriptome complexity than is captured by existing annotation. The pervasive nature of overlapping transcription throughout herpesvirus genomes, however, poses substantial problems in resolving transcript structures using these methods alone. We present an approach that combines the unique attributes of Pacific Biosciences Iso-Seq long-read, Illumina short-read and deepCAGE (Cap Analysis of Gene Expression) sequencing to globally resolve polyadenylated isoform structures in replicating Epstein-Barr virus (EBV). Our method, Transcriptome Resolution through Integration of Multi-platform Data (TRIMD), identifies nearly 300 novel EBV transcripts, quadrupling the size of the annotated viral transcriptome. These findings illustrate an array of mechanisms through which EBV achieves functional diversity in its relatively small, compact genome including programmed alternative splicing (e.g. across the IR1 repeats), alternative promoter usage by LMP2 and other latency-associated transcripts, intergenic splicing at the BZLF2 locus, and antisense transcription and pervasive readthrough transcription throughout the genome.

New Noncoding Lytic Transcripts Derived from the Epstein-Barr Virus Latency Origin of Replication, oriP, Are Hyperedited, Bind the Paraspeckle Protein, NONO/p54nrb, and Support Viral Lytic Transcription.

UNLABELLED: We have previously shown that the Epstein-Barr virus (EBV) likely encodes hundreds of viral long noncoding RNAs (vlncRNAs) that are expressed during reactivation. Here we show that the EBV latency origin of replication (oriP) is transcribed bi-directionally during reactivation and that both leftward (oriPtLs) and rightward (oriPtRs) transcripts are largely localized in the nucleus. While the oriPtLs are most likely noncoding, at least some of the oriPtRs contain the BCRF1/vIL10 open reading frame. Nonetheless, oriPtR transcripts with long 5' untranslated regions may partially serve noncoding functions. Both oriPtL and oriPtR transcripts are expressed with late kinetics, and their expression is inhibited by phosphonoacetic acid. RNA sequencing (RNA-seq) analysis showed that oriPtLs and oriPtRs exhibited extensive "hyperediting" at their Family of Repeat (FR) regions. RNA secondary structure prediction revealed that the FR region of both oriPtLs and oriPtRs may form large evolutionarily conserved and thermodynamically stable hairpins. The double-stranded RNA-binding protein and RNA-editing enzyme ADAR was found to bind to oriPtLs, likely facilitating editing of the FR hairpin. Further, the multifunctional paraspeckle protein, NONO, was found to bind to oriPt transcripts, suggesting that oriPts interact with the paraspeckle-based innate antiviral immune pathway. Knockdown and ectopic expression of oriPtLs showed that it contributes to global viral lytic gene expression and viral DNA replication. Together, these results show that these new vlncRNAs interact with cellular innate immune pathways and that they help facilitate progression of the viral lytic cascade. IMPORTANCE: Recent studies have revealed that the complexity of lytic herpesviral transcriptomes is significantly greater than previously appreciated with hundreds of viral long noncoding RNAs (vlncRNAs) being recently discovered. Work on cellular lncRNAs over the past several years has just begun to give us an initial appreciation for the array of functions they play in complex formation and regulatory processes in the cell. The newly identified herpesvirus lncRNAs are similarly likely to play a variety of different functions, although these functions are likely tailored to specific needs of the viral infection cycles. Here we describe novel transcripts derived from the EBV latency origin of replication. We show that they are hyperedited, that they interact with a relatively newly appreciated antiviral pathway, and that they play a role in facilitating viral lytic gene expression. These investigations are a starting point to unraveling the complex arena of vlncRNA function in herpesvirus lytic replication.

Kinetic and structural analysis of fluorescent peptides on cotton cellulose nanocrystals as elastase sensors.

Human neutrophil elastase (HNE) and porcine pancreatic elastase (PPE) are serine proteases with destructive proteolytic activity. Because of this activity, there is considerable interest in elastase sensors. Herein we report the synthesis, characterization, and kinetic profiles of tri- and tetrapeptide substrates of elastase as glycine-esterified fluorescent analogs of cotton cellulose nanocrystals (CCN). The degree of substitution of peptide incorporated in CCN was 3-4 peptides per 100 anhydroglucose units. Glycine and peptide-cellulose-nanocrystals revealed crystallinity indices of 79 and 76%, respectively, and a crystallite size of 58.5 Å. A crystallite model of the peptide-cellulose conjugate is shown. The tripeptide conjugate of CCN demonstrated five-fold greater efficiency in HNE than the tripeptide in solution judged by its kcat/Km of 33,515. The sensor limits of detection at 2mg of the tri- and tetrapeptide CCN conjugates over a 10 min reaction time course were 0.03 U/mL PPE and 0.05 U/mL HNE, respectively.

High-throughput RNA sequencing-based virome analysis of 50 lymphoma cell lines from the Cancer Cell Line Encyclopedia project.

UNLABELLED: Using high-throughput RNA sequencing data from 50 common lymphoma cell culture models from the Cancer Cell Line Encyclopedia project, we performed an unbiased global interrogation for the presence of a panel of 740 viruses and strains known to infect human and other mammalian cells. This led to the findings of previously identified infections by Epstein-Barr virus (EBV), Kaposi's sarcoma herpesvirus (KSHV), and human T-lymphotropic virus type 1 (HTLV-1). In addition, we also found a previously unreported infection of one cell line (DEL) with a murine leukemia virus. High expression of murine leukemia virus (MuLV) transcripts was observed in DEL cells, and we identified four transcriptionally active integration sites, one being in the TNFRSF6B gene. We also found low levels of MuLV reads in a number of other cell lines and provided evidence suggesting cross-contamination during sequencing. Analysis of HTLV-1 integrations in two cell lines, HuT 102 and MJ, identified 14 and 66 transcriptionally active integration sites with potentially activating integrations in immune regulatory genes, including interleukin-15 (IL-15), IL-6ST, STAT5B, HIVEP1, and IL-9R. Although KSHV and EBV do not typically integrate into the genome, we investigated a previously identified integration of EBV into the BACH2 locus in Raji cells. This analysis identified a BACH2 disruption mechanism involving splice donor sequestration. Through viral gene expression analysis, we detected expression of stable intronic RNAs from the EBV BamHI W repeats that may be part of long transcripts spanning the repeat region. We also observed transcripts at the EBV vIL-10 locus exclusively in the Hodgkin's lymphoma cell line, Hs 611.T, the expression of which were uncoupled from other lytic genes. Assessment of the KSHV viral transcriptome in BCP-1 cells showed expression of the viral immune regulators, K2/vIL-6, K4/vIL-8-like vCCL1, and K5/E2-ubiquitin ligase 1 that was significantly higher than expression of the latency-associated nuclear antigen. Together, this investigation sheds light into the virus composition across these lymphoma model systems and provides insights into common viral mechanistic principles. IMPORTANCE: Viruses cause cancer in humans. In lymphomas the Epstein-Barr virus (EBV), Kaposi's sarcoma herpesvirus (KSHV) and human T-lymphotropic virus type 1 are major contributors to oncogenesis. We assessed virus-host interactions using a high throughput sequencing method that facilitates the discovery of new virus-host associations and the investigation into how the viruses alter their host environment. We found a previously unknown murine leukemia virus infection in one cell line. We identified cellular genes, including cytokine regulators, that are disrupted by virus integration, and we determined mechanisms through which virus integration causes deregulation of cellular gene expression. Investigation into the KSHV transcriptome in the BCP-1 cell line revealed high-level expression of immune signaling genes. EBV transcriptome analysis showed expression of vIL-10 transcripts in a Hodgkin's lymphoma that was uncoupled from lytic genes. These findings illustrate unique mechanisms of viral gene regulation and to the importance of virus-mediated host immune signaling in lymphomas.

Sarna sarcóptica: comunicación de un brote en un grupo familiar y su mascota / Sarcoptic mange: report of an outbreak in a family and their pet

Scabies caused by the genus Sarcoptes scabiei var canis is a prevalent infection in dogs and affects abandoned, malnourished and overcrowded animals, causing hair loss and an intensely pruritic crusting dermatitis. In humans the manifestation is a self-limiting pruritic dermatitis, but persistent cases are described. An outbreak of sarcoptic mange is reported in a family group (seven people, including a 5 month infant and his mother). The infective source was their own house dog who was taken from the street. The diagnosis was confirmed by the detection of mites and eggs in the acarotest of the dog and mites of S. scabei in the infant. Sarcoptic mange should be suspected in individuals with allergic dermatitis who have contact with dogs. Treatment in humans is usually symptomatic and may need miticides if the infection persists. The control of the disease requires an appropriate pet treatment.

La sarna producida por el género Sarcoptes scabiei var canis, infección prevalente en perros y de alto potencial zoonótico, afecta a animales abandonados, desnutridos y hacinados y causa alopecia y una dermatitis costrosa intensamente pruriginosa. En el ser humano produce una dermatitis pruriginosa generalmente autolimitada, pero se describen casos persistentes. Se reporta un brote de sarna sarcóptica en un grupo familiar (siete personas, incluidas una lactante y su madre) cuya fuente de infección fue su mascota canina recogida de la calle. El diagnóstico fue confirmado por visualización en el ácarotest de ácaros y huevos en el perro y ácaros de S. scabiei en la lactante. La sarna sarcóptica debe sospecharse en casos de dermatitis alérgica en personas con contacto con perros. El tratamiento en el humano, habitualmente sintomático, puede necesitar acaricidas si el cuadro persiste. El control de la enfermedad requiere el adecuado tratamiento de la mascota.

Global bidirectional transcription of the Epstein-Barr virus genome during reactivation.

Epstein-Barr virus (EBV) reactivation involves the ordered induction of approximately 90 viral genes that participate in the generation of infectious virions. Using strand-specific RNA-seq to assess the EBV transcriptome during reactivation, we found extensive bidirectional transcription extending across nearly the entire genome. In contrast, only 4% of the EBV genome is currently bidirectionally annotated. Most of the newly identified transcribed regions show little evidence of coding potential, supporting noncoding roles for most of these RNAs. Based on previous cellular long noncoding RNA size calculations, we estimate that there are likely hundreds more EBV genes expressed during reactivation than was previously known. Limited 5' and 3' rapid amplification of cDNA ends (RACE) experiments and findings of novel splicing events by RNA-seq suggest that the complexity of the viral genome during reactivation may be even greater. Further analysis of antisense transcripts at some of the EBV latency gene loci showed that they are "late" genes, they are nuclear, and they tend to localize in areas of the nucleus where others find newly synthesized viral genomes. This raises the possibility that these transcripts perform functions such as new genome processing, stabilization, organization, etc. The finding of a significantly more complex EBV transcriptome during reactivation changes our view of the viral production process from one that is facilitated and regulated almost entirely by previously identified viral proteins to a process that also involves the contribution of a wide array of virus encoded noncoding RNAs. Epstein-Barr virus (EBV) is a herpesvirus that infects the majority of the world's population, in rare cases causing serious disease such as lymphoma and gastric carcinoma. Using strand-specific RNA-seq, we have studied viral gene expression during EBV reactivation and have discovered hundreds more viral transcripts than were previously known. The finding of alternative splicing and the prevalence of overlapping transcripts indicate additional complexity. Most newly identified transcribed regions do not encode proteins but instead likely function as noncoding RNA molecules which could participate in regulating gene expression, gene splicing or even activities such as viral genome processing. These findings broaden the scope of what we need to consider to understand the viral manufacturing process. As more detailed studies are undertaken they will likely change the way we view this process as a whole.

Differences in gastric carcinoma microenvironment stratify according to EBV infection intensity: implications for possible immune adjuvant therapy.

Epstein-Barr virus (EBV) is associated with roughly 10% of gastric carcinomas worldwide (EBVaGC). Although previous investigations provide a strong link between EBV and gastric carcinomas, these studies were performed using selected EBV gene probes. Using a cohort of gastric carcinoma RNA-seq data sets from The Cancer Genome Atlas (TCGA), we performed a quantitative and global assessment of EBV gene expression in gastric carcinomas and assessed EBV associated cellular pathway alterations. EBV transcripts were detected in 17% of samples but these samples varied significantly in EBV coverage depth. In four samples with the highest EBV coverage (hiEBVaGC - high EBV associated gastric carcinoma), transcripts from the BamHI A region comprised the majority of EBV reads. Expression of LMP2, and to a lesser extent, LMP1 were also observed as was evidence of abortive lytic replication. Analysis of cellular gene expression indicated significant immune cell infiltration and a predominant IFNG response in samples expressing high levels of EBV transcripts relative to samples expressing low or no EBV transcripts. Despite the apparent immune cell infiltration, high levels of the cytotoxic T-cell (CTL) and natural killer (NK) cell inhibitor, IDO1, was observed in the hiEBVaGCs samples suggesting an active tolerance inducing pathway in this subgroup. These results were confirmed in a separate cohort of 21 Vietnamese gastric carcinoma samples using qRT-PCR and on tissue samples using in situ hybridization and immunohistochemistry. Lastly, a panel of tumor suppressors and candidate oncogenes were expressed at lower levels in hiEBVaGC versus EBV-low and EBV-negative gastric cancers suggesting the direct regulation of tumor pathways by EBV.

Whole-genome sequencing of the Akata and Mutu Epstein-Barr virus strains.

Using a simple viral genome enrichment approach, we report the de novo assembly of the Akata and Mutu Epstein-Barr virus (EBV) genomes from a single lane of next-generation sequencing (NGS) reads. The Akata and Mutu viral genomes are type I EBV strains of approximately 171 kb in length. Evidence for genome heterogeneity was found for the Akata but not for the Mutu strain. A comparative analysis of Akata with another four completely sequenced EBV strains, B95-8/Raji, AG876, Mutu, and GD1, demonstrated that the Akata strain is most closely related to the GD1 strain and exhibits the greatest divergence from the type II strain, AG876. A global comparison of latent and lytic gene sequences showed that the four latency genes, EBNA2, EBNA3A, EBNA3B, and EBNA3C, are uniquely defining of type I and type II strain differences. Within type I strains, LMP1, the latency gene, is among the most divergent of all EBV genes, with three insertion or deletion loci in its CTAR2 and CTAR3 signaling domains. Analysis of the BHLF1 and LF3 genes showed that the reading frames identified in the B95-8/Raji genome are not conserved in Akata (or Mutu, for BHLF1), suggesting a primarily non-protein-coding function in EBV's life cycle. The Akata and Mutu viral-genome sequences should be a useful resource for homology-based functional prediction and for molecular studies, such as PCR, RNA-seq, recombineering, and transcriptome studies. As an illustration, we identified novel RNA-editing events in ebv-miR-BART6 antisense transcripts using the Akata and Mutu reference genomes.

Identification of new viral genes and transcript isoforms during Epstein-Barr virus reactivation using RNA-Seq.

Using an enhanced RNA-Seq pipeline to analyze Epstein-Barr virus (EBV) transcriptomes, we investigated viral and cellular gene expression in the Akata cell line following B-cell-receptor-mediated reactivation. Robust induction of EBV gene expression was observed, with most viral genes induced >200-fold and with EBV transcripts accounting for 7% of all mapped reads within the cell. After induction, hundreds of candidate splicing events were detected using the junction mapper TopHat, including a novel nonproductive splicing event at the gp350/gp220 locus and several alternative splicing events at the LMP2 locus. A more detailed analysis of lytic LMP2 transcripts showed an overall lack of the prototypical type III latency splicing events. Analysis of nuclear versus cytoplasmic RNA-Seq data showed that the lytic forms of LMP2, EBNA-2, EBNA-LP, and EBNA-3A, -3B, and -3C have higher nuclear-to-cytoplasmic accumulation ratios than most lytic genes, including classic late genes. These data raise the possibility that at least some lytic transcripts derived from these latency gene loci may have unique, noncoding nuclear functions during reactivation. Our analysis also identified two previously unknown genes, BCLT1 and BCRT2, that map to the BamHI C-region of the EBV genome. Pathway analysis of cellular gene expression changes following B-cell receptor activation identified an inflammatory response as the top predicted function and ILK and TREM1 as the top predicted canonical pathways.

Analysis of the reaction force for a gas phase S(N)2 process: CH3Cl + H2O --> CH3OH + HCl.

The "reaction force" F(R(c)) is the negative derivative of a system's potential energy V(R(c)) along the intrinsic reaction coordinate of a process. If V(R(c)) goes through a maximum, as is commonly the case, then F(R(c)) has a characteristic profile: a negative minimum followed by zero at the transition state and then a positive maximum. These features reflect four phases of the reaction: an initial one of reactant preparation, followed by two of transition to products, and then relaxation of the latter. In this study, we have analyzed, in these terms, a gas-phase S(N)2 substitution, selected to be CH3Cl + H2O --> CH3OH + HCl. We examine, at the B3LYP/6-31G level, the geometries, energetics, and molecular surface electrostatic potentials, local ionization energies, and internal charge separation.

Un caso de anisakiosis en un adulto / An adult anisakiosis case

Un paciente de 38 años de edad con antecedentes de haber comido pescado crudo (mariscal) doce horas antes, presentó un severo dolor gástrico y eliminó por vía bucal una larva de nematodo de aproximadamente 20 mm de largo. La endoscopia mostró una leve gastritis, sin evidenciar la presencia de otras larvas o lesiones ulcerosas. El dolor desapareció totalmente a las dos semanas luego de un tratamiento con antihistamínicos y analgésicos