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Viruses are the cause of a considerable burden to human, animal and plant health, whileon the other hand playing an important role in regulating entire ecosystems. The power of newsequencing technologies combined with new tools for processing “Big Data” offers unprecedentedopportunities to answer fundamental questions in virology. Virologists have an urgent need forvirus-specific bioinformatics tools. These developments have led to the formation of the EuropeanVirus Bioinformatics Center, a network of experts in virology and bioinformatics who are joiningforces to enable extensive exchange and collaboration between these research areas. The EVBCstrives to provide talented researchers with a supportive environment free of gender bias, but thegender gap in science, especially in math-intensive fields such as computer science, persists. Tobring more talented women into research and keep them there, we need to highlight role models tospark their interest, and we need to ensure that female scientists are not kept at lower levels but aregiven the opportunity to lead the field. Here we showcase the work of the EVBC and highlight theachievements of some outstanding women experts in virology and viral bioinformatics.

Viruses are the cause of a considerable burden to human, animal and plant health, whileon the other hand playing an important role in regulating entire ecosystems. The power of newsequencing technologies combined with new tools for processing “Big Data” offers unprecedentedopportunities to answer fundamental questions in virology. Virologists have an urgent need forvirus-specific bioinformatics tools. These developments have led to the formation of the EuropeanVirus Bioinformatics Center, a network of experts in virology and bioinformatics who are joiningforces to enable extensive exchange and collaboration between these research areas. The EVBCstrives to provide talented researchers with a supportive environment free of gender bias, but thegender gap in science, especially in math-intensive fields such as computer science, persists. Tobring more talented women into research and keep them there, we need to highlight role models tospark their interest, and we need to ensure that female scientists are not kept at lower levels but aregiven the opportunity to lead the field. Here we showcase the work of the EVBC and highlight theachievements of some outstanding women experts in virology and viral bioinformatics.

Viruses are the cause of a considerable burden to human, animal and plant health, whileon the other hand playing an important role in regulating entire ecosystems. The power of newsequencing technologies combined with new tools for processing “Big Data” offers unprecedentedopportunities to answer fundamental questions in virology. Virologists have an urgent need forvirus-specific bioinformatics tools. These developments have led to the formation of the EuropeanVirus Bioinformatics Center, a network of experts in virology and bioinformatics who are joiningforces to enable extensive exchange and collaboration between these research areas. The EVBCstrives to provide talented researchers with a supportive environment free of gender bias, but thegender gap in science, especially in math-intensive fields such as computer science, persists. Tobring more talented women into research and keep them there, we need to highlight role models tospark their interest, and we need to ensure that female scientists are not kept at lower levels but aregiven the opportunity to lead the field. Here we showcase the work of the EVBC and highlight theachievements of some outstanding women experts in virology and viral bioinformatics.

Viruses are the cause of a considerable burden to human, animal and plant health, whileon the other hand playing an important role in regulating entire ecosystems. The power of newsequencing technologies combined with new tools for processing “Big Data” offers unprecedentedopportunities to answer fundamental questions in virology. Virologists have an urgent need forvirus-specific bioinformatics tools. These developments have led to the formation of the EuropeanVirus Bioinformatics Center, a network of experts in virology and bioinformatics who are joiningforces to enable extensive exchange and collaboration between these research areas. The EVBCstrives to provide talented researchers with a supportive environment free of gender bias, but thegender gap in science, especially in math-intensive fields such as computer science, persists. Tobring more talented women into research and keep them there, we need to highlight role models tospark their interest, and we need to ensure that female scientists are not kept at lower levels but aregiven the opportunity to lead the field. Here we showcase the work of the EVBC and highlight theachievements of some outstanding women experts in virology and viral bioinformatics.

Viruses are the cause of a considerable burden to human, animal and plant health, whileon the other hand playing an important role in regulating entire ecosystems. The power of newsequencing technologies combined with new tools for processing “Big Data” offers unprecedentedopportunities to answer fundamental questions in virology. Virologists have an urgent need forvirus-specific bioinformatics tools. These developments have led to the formation of the EuropeanVirus Bioinformatics Center, a network of experts in virology and bioinformatics who are joiningforces to enable extensive exchange and collaboration between these research areas. The EVBCstrives to provide talented researchers with a supportive environment free of gender bias, but thegender gap in science, especially in math-intensive fields such as computer science, persists. Tobring more talented women into research and keep them there, we need to highlight role models tospark their interest, and we need to ensure that female scientists are not kept at lower levels but aregiven the opportunity to lead the field. Here we showcase the work of the EVBC and highlight theachievements of some outstanding women experts in virology and viral bioinformatics.

Viruses are the cause of a considerable burden to human, animal and plant health, while on the other hand playing an important role in regulating entire ecosystems. The power of new sequencing technologies combined with new tools for processing "Big Data" offers unprecedented opportunities to answer fundamental questions in virology. Virologists have an urgent need for virus-specific bioinformatics tools. These developments have led to the formation of the European Virus Bioinformatics Center, a network of experts in virology and bioinformatics who are joining forces to enable extensive exchange and collaboration between these research areas. The EVBC strives to provide talented researchers with a supportive environment free of gender bias, but the gender gap in science, especially in math-intensive fields such as computer science, persists. To bring more talented women into research and keep them there, we need to highlight role models to spark their interest, and we need to ensure that female scientists are not kept at lower levels but are given the opportunity to lead the field. Here we showcase the work of the EVBC and highlight the achievements of some outstanding women experts in virology and viral bioinformatics.

Single-cell RNA sequencing offers snapshots of whole transcriptomes but obscures the temporal RNA dynamics. Here we present single-cell metabolically labeled new RNA tagging sequencing (scNT-seq), a method for massively parallel analysis of newly transcribed and pre-existing mRNAs from the same cell. This droplet microfluidics-based method enables high-throughput chemical conversion on barcoded beads, efficiently marking newly transcribed mRNAs with T-to-C substitutions. Using scNT-seq, we jointly profiled new and old transcriptomes in ~55,000 single cells. These data revealed time-resolved transcription factor activities and cell-state trajectories at the single-cell level in response to neuronal activation. We further determined rates of RNA biogenesis and decay to uncover RNA regulatory strategies during stepwise conversion between pluripotent and rare totipotent two-cell embryo (2C)-like stem cell states. Finally, integrating scNT-seq with genetic perturbation identifies DNA methylcytosine dioxygenase as an epigenetic barrier into the 2C-like cell state. Time-resolved single-cell transcriptomic analysis thus opens new lines of inquiry regarding cell-type-specific RNA regulatory mechanisms.

Eukaryotic gene expression is extensively regulated by cellular stress and pathogen infections. We have previously shown that herpes simplex virus 1 (HSV-1) and several cellular stresses cause widespread disruption of transcription termination (DoTT) of RNA polymerase II (RNAPII) in host genes and that the viral immediate early factor ICP27 plays an important role in HSV-1-induced DoTT. Here, we show that HSV-1 infection also leads to widespread changes in alternative polyadenylation (APA) of host mRNAs. In the majority of cases, polyadenylation shifts to upstream poly(A) sites (PAS), including many intronic PAS. Mechanistically, ICP27 contributes to HSV-1-mediated APA regulation. HSV-1- and ICP27-induced activation of intronic PAS is sequence-dependent and does not involve general inhibition of U1 snRNP. HSV1-induced intronic polyadenylation is accompanied by early termination of RNAPII. HSV-1-induced mRNAs polyadenylated at intronic PAS (IPA) are exported into the cytoplasm while APA isoforms with extended 3' UTRs are sequestered in the nuclei, both preventing the expression of the full-length gene products. Finally we provide evidence that HSV-induced IPA isoforms are translated. Together with other recent studies, our results suggest that viral infection and cellular stresses induce a multi-faceted host response that includes DoTT and changes in APA profiles.

Eukaryotic gene expression is extensively regulated by cellular stress and pathogen infections. We have previously shown that herpes simplex virus 1 (HSV-1) and several cellular stresses cause widespread disruption of transcription termination (DoTT) of RNA polymerase II (RNAPII) in host genes and that the viral immediate early factor ICP27 plays an important role in HSV-1-induced DoTT. Here, we show that HSV-1 infection also leads to widespread changes in alternative polyadenylation (APA) of host mRNAs. In the majority of cases, polyadenylation shifts to upstream poly(A) sites (PAS), including many intronic PAS. Mechanistically, ICP27 contributes to HSV-1-mediated APA regulation. HSV-1- and ICP27-induced activation of intronic PAS is sequence-dependent and does not involve general inhibition of U1 snRNP. HSV1-induced intronic polyadenylation is accompanied by early termination of RNAPII. HSV-1-induced mRNAs polyadenylated at intronic PAS (IPA) are exported into the cytoplasm while APA isoforms with extended 3' UTRs are sequestered in the nuclei, both preventing the expression of the full-length gene products. Finally we provide evidence that HSV-induced IPA isoforms are translated. Together with other recent studies, our results suggest that viral infection and cellular stresses induce a multi-faceted host response that includes DoTT and changes in APA profiles.

Infection by viruses, including herpes simplex virus-1 (HSV-1), and cellular stresses cause widespread disruption of transcription termination (DoTT) of RNA polymerase II (RNAPII) in host genes. However, the underlying mechanisms remain unclear. Here, we demonstrate that the HSV-1 immediate early protein ICP27 induces DoTT by directly binding to the essential mRNA 3' processing factor CPSF. It thereby induces the assembly of a dead-end 3' processing complex, blocking mRNA 3' cleavage. Remarkably, ICP27 also acts as a sequence-dependent activator of mRNA 3' processing for viral and a subset of host transcripts. Our results unravel a bimodal activity of ICP27 that plays a key role in HSV-1-induced host shutoff and identify CPSF as an important factor that mediates regulation of transcription termination. These findings have broad implications for understanding the regulation of transcription termination by other viruses, cellular stress and cancer.

Infection by viruses, including herpes simplex virus-1 (HSV-1), and cellular stresses cause widespread disruption of transcription termination (DoTT) of RNA polymerase II (RNAPII) in host genes. However, the underlying mechanisms remain unclear. Here, we demonstrate that the HSV-1 immediate early protein ICP27 induces DoTT by directly binding to the essential mRNA 3' processing factor CPSF. It thereby induces the assembly of a dead-end 3' processing complex, blocking mRNA 3' cleavage. Remarkably, ICP27 also acts as a sequence-dependent activator of mRNA 3' processing for viral and a subset of host transcripts. Our results unravel a bimodal activity of ICP27 that plays a key role in HSV-1-induced host shutoff and identify CPSF as an important factor that mediates regulation of transcription termination. These findings have broad implications for understanding the regulation of transcription termination by other viruses, cellular stress and cancer.

DNA damage response (DDR) involves dramatic transcriptional alterations, the mechanisms of which remain ill defined. Here, we show that following genotoxic stress, the RNA-binding motif protein 7 (RBM7) stimulates RNA polymerase II (Pol II) transcription and promotes cell viability by activating the positive transcription elongation factor b (P-TEFb) via its release from the inhibitory 7SK small nuclear ribonucleoprotein (7SK snRNP). This is mediated by activation of p38MAPK, which triggers enhanced binding of RBM7 with core subunits of 7SK snRNP. In turn, P-TEFb relocates to chromatin to induce transcription of short units, including key DDR genes and multiple classes of non-coding RNAs. Critically, interfering with the axis of RBM7 and P-TEFb provokes cellular hypersensitivity to DNA-damage-inducing agents due to activation of apoptosis. Our work uncovers the importance of stress-dependent stimulation of Pol II pause release, which enables a pro-survival transcriptional response that is crucial for cell fate upon genotoxic insult.

DNA damage response (DDR) involves dramatic transcriptional alterations, the mechanisms of which remain ill defined. Here, we show that following genotoxic stress, the RNA-binding motif protein 7 (RBM7) stimulates RNA polymerase II (Pol II) transcription and promotes cell viability by activating the positive transcription elongation factor b (P-TEFb) via its release from the inhibitory 7SK small nuclear ribonucleoprotein (7SK snRNP). This is mediated by activation of p38MAPK, which triggers enhanced binding of RBM7 with core subunits of 7SK snRNP. In turn, P-TEFb relocates to chromatin to induce transcription of short units, including key DDR genes and multiple classes of non-coding RNAs. Critically, interfering with the axis of RBM7 and P-TEFb provokes cellular hypersensitivity to DNA-damage-inducing agents due to activation of apoptosis. Our work uncovers the importance of stress-dependent stimulation of Pol II pause release, which enables a pro-survival transcriptional response that is crucial for cell fate upon genotoxic insult.

Herpesviruses constitute a family of large DNA viruses widely spread in vertebrates and causing a variety of different diseases. They possess dsDNA genomes ranging from 120 to 240 kbp encoding between 70 to 170 open reading frames. We previously reported the protein interaction networks of two herpesviruses, varicella-zoster virus (VZV) and Kaposi's sarcoma-associated herpesvirus (KSHV). In this study, we systematically tested three additional herpesvirus species, herpes simplex virus 1 (HSV-1), murine cytomegalovirus and Epstein-Barr virus, for protein interactions in order to be able to perform a comparative analysis of all three herpesvirus subfamilies. We identified 735 interactions by genome-wide yeast-two-hybrid screens (Y2H), and, together with the interactomes of VZV and KSHV, included a total of 1,007 intraviral protein interactions in the analysis. Whereas a large number of interactions have not been reported previously, we were able to identify a core set of highly conserved protein interactions, like the interaction between HSV-1 UL33 with the nuclear egress proteins UL31/UL34. Interactions were conserved between orthologous proteins despite generally low sequence similarity, suggesting that function may be more conserved than sequence. By combining interactomes of different species we were able to systematically address the low coverage of the Y2H system and to extract biologically relevant interactions which were not evident from single species.

Herpesviruses constitute a family of large DNA viruses widely spread in vertebrates and causing a variety of different diseases. They possess dsDNA genomes ranging from 120 to 240 kbp encoding between 70 to 170 open reading frames. We previously reported the protein interaction networks of two herpesviruses, varicella-zoster virus (VZV) and Kaposi's sarcoma-associated herpesvirus (KSHV). In this study, we systematically tested three additional herpesvirus species, herpes simplex virus 1 (HSV-1), murine cytomegalovirus and Epstein-Barr virus, for protein interactions in order to be able to perform a comparative analysis of all three herpesvirus subfamilies. We identified 735 interactions by genome-wide yeast-two-hybrid screens (Y2H), and, together with the interactomes of VZV and KSHV, included a total of 1,007 intraviral protein interactions in the analysis. Whereas a large number of interactions have not been reported previously, we were able to identify a core set of highly conserved protein interactions, like the interaction between HSV-1 UL33 with the nuclear egress proteins UL31/UL34. Interactions were conserved between orthologous proteins despite generally low sequence similarity, suggesting that function may be more conserved than sequence. By combining interactomes of different species we were able to systematically address the low coverage of the Y2H system and to extract biologically relevant interactions which were not evident from single species.