Project description:These findings establish minion as a novel microprotein required for muscle development, and define a two-component program for the induction of mammalian cell fusion.
Project description:To evaluate targeted MinION next generation sequencing as a diagnostic method for detection of pathogens in human blood and plasma, human blood or plasma samples were spiked with measured amounts of viruses, bacteria, protozoan parasites or tested pathogen-free as negative controls. Nucleic acid was extracted from samples and PCR amplification performed in multiplex primer pools with a procedure described in ArrayExpress experiment submission ID 18379. The PCR products were used for library preparation. The libraries sequenced on an Oxford Nanopore MinION. The passed reads aligned with a custom reference file to determine the identity of the pathogen in the sample.
Project description:The human facilitates chromatin transcription (FACT) complex is a chromatin remodeller composed of human suppressor of Ty 16 homologue (hSpt16) and structure-specific recognition protein-1 subunits that regulates cellular gene expression. Whether FACT regulates host responses to infection remained unclear. We identify a FACT-mediated, interferon-independent, antiviral pathway that restricts poxvirus replication. Cell culture and bioinformatics approaches suggest that early viral gene expression triggers nuclear accumulation of SUMOylated hSpt16 subunits required for the expression of E26 transformation-specific sequence-1 (ETS-1)-a transcription factor that activates virus restriction programs. However, biochemical studies show that poxvirus-encoded A51R proteins block ETS-1 expression by outcompeting structure-specific recognition protein-1 binding to SUMOylated hSpt16 and by tethering SUMOylated hSpt16 to microtubules. Furthermore, A51R antagonism of FACT enhances poxvirus replication in human cells and virulence in mice. Finally, we show that FACT also restricts rhabdoviruses, flaviviruses and orthomyxoviruses, suggesting broad roles for FACT in antiviral immunity. Our study reveals the FACT-ETS-1 antiviral response (FEAR) pathway to be critical for eukaryotic antiviral immunity and describes a unique mechanism of viral immune evasion.
Project description:Viral RNA polymerases (vRNAPs) can slip on homopolymeric sequences to expand their coding potential in diverse ways. This includes poxviruses, whose vRNAP slips at thymidine-rich motifs to generate non-templated polyadenosine (polyA) leaders on certain transcripts. However, we lack a comprehensive genome-wide understanding of poxviral 5’ leaders and their capping status. Here, we developed Mapping 5′ Untranslated Regions of Viral transcripts (MURV-seq), a customized transcript capture, sequencing and data analysis strategy that distinguishes 5′ triphosphate (5′ppp) versus 7-methylguanosine (m7G) termini and provides high-resolution sequences for the leaders of all annotated poxvirus open reading frames (ORFs). MURV-seq reveals extensive diversity and temporal shifts in the use of templated and non-templated leaders by individual genes. We further define three distinct polyA leader types and refine our understanding of variance in their lengths both between kinetic classes and across individual genes. Contrary to recent suggestions that long polyA leaders generally lack canonical caps, we find that this only occurs on a small fraction of transcripts while all viral transcript types predominantly retain m7G caps. Moreover, while many early genes utilize templated leaders, as expected, transcription upstream of canonical vRNAP slippage sites produces alternative templated leaders for many intermediate and late ORFs. Computational analysis suggests that some of these harbor short upstream ORFs that likely limit their use as 5’ untranslated regions (UTRs), while others are predicted to be functional for the primary ORF or in producing N-terminally extended isoforms. Combined, MURV-seq provides a genome-wide framework for understanding poxvirus transcription start sites and leader diversity.