Project description:Human cells identify invading pathogens and activate immune signaling pathways through a wide array of pattern recognition receptors, such as DNA sensors. The interferon-inducible protein 16 (IFI16) is a nuclear DNA sensor that recognizes double-stranded DNA from a number of viral sources, including genomes of nuclear-replicating viruses such as the prevalent human pathogen, herpes simplex virus 1 (HSV-1). Upon binding to the DNA genome of HSV-1, IFI16 both induces antiviral cytokine expression and suppresses virus gene expression. Here, we use a multi-omics approach of DNA sequencing techniques paired with targeted mass spectrometry to obtain an extensive view of the interaction between IFI16 and the HSV-1 genome, and how this binding affects the viral DNA structure and protein expression. Through ChIP-seq, we find that IFI16 binds to the HSV-1 genome in a sequence-independent manner while simultaneously exhibiting broad enrichment at two loci: UL30, the viral DNA polymerase gene, and US1-US7. ATAC-seq analysis reveals that these two regions are among the most accessible stretches of DNA on the genome, thereby facilitating IFI16 binding. Accessibility of the entire HSV-1 genome is elevated upon IFI16-KO, indicating that expression of IFI16 globally induces chromatinization of viral DNA, regardless of IFI16 enrichment. Deletion of IFI16 also results in a global increase in the expression of HSV-1 proteins, as measured by parallel reaction monitoring-mass spectrometry. Altogether, we demonstrate that IFI16 interacts with the HSV-1 genome in a sequence-independent manner, and this interaction coordinates epigenetic silencing of the viral genome, resulting in decreased protein expression and virus replication.
Project description:To understand the regulatory regions of genomic DNA by nuclear pore, the genomic region associated by NUP153, one of nuclear pore protein, was determined by Chromatin immunoprecipitation DNA-sequencing (ChIP-seq) .
Project description:Ribosome biogenesis is a highly complex process in eukaryotes, involving temporally and spatially regulated ribosomal protein (r-protein) binding and rRNA remodeling events in the nucleolus, nucleoplasm and cytoplasm. Hundreds of assembly factors (AFs), organized into sequential functional groups, facilitate and guide the maturation process into productive assembly branches in and across different cellular compartments. However, the precise mechanisms by which these AFs function are largely unknown. Here, we use cryo-electron microscopy (cryo-EM), to characterize the structures of yeast nucleoplasmic pre-60S particles affinity-purified using the epitope-tagged AF Nog2. Our data pinpoint the locations and determine the structures of over 20 AFs, which are enriched in two areas, an arc region extending from the central protuberance (CP) to the polypeptide tunnel exit (PTE), and the domain including the internal transcribed spacer 2 (ITS2) that separates 5.8S and 25S rRNAs. These structural data suggest that the arc-located factors might function to chaperone formation of RNA helices found in the active sites of the subunit, including helices from the CP, peptidyl-transferase center (PTC) and intersubunit bridge. In particular, two regulatory GTPases, Nog2 and Nog1, act as hub proteins to interact with multiple, distant AFs and functional rRNA elements, manifesting their critical roles in structural remodeling checkpoints and nuclear export. Moreover, our snapshots of compositionally and structurally different pre-60S intermediates provide essential mechanistic details for three major remodeling events before nuclear export: rotation of the 5S RNP, construction of the active center, and ITS2 removal. Therefore, our structures provide a framework to understand the molecular roles of diverse AFs, and potentially the atomic information therein constitutes a resource to generalize principles governing the elusive functions of nuclear RNA-binding proteins.
Project description:How gene positioning to the nuclear periphery regulates transcription remains largely unclear. We have previously observed the differential compartmentalization of transcription factors and histone modifications at the nuclear periphery in mouse C2C12 myoblasts. Here, we have integrated high throughput DNA sequencing into the DNA adenine methyltransferase identification (DamID) assay, and have identified ~15, 000 sequencing-based Lamina-Associated Domains (sLADs) in mouse 3T3 fibroblasts and C2C12 myoblasts. These genomic regions range from a few kb to over 1 Mb and cover ~30% of the genome, and are spatially proximal to the nuclear lamina (NL). Active histone modifications such as H3K4me2, H3K9Ac, H3K36me3 and H3K79me2 are all localized away from the nuclear periphery microscopically, and distributed predominantly out of sLADs genome-wide. Therefore, the spatial compartmentalization of active histone modifications likely characterizes a major portion of chromatin at the nuclear periphery in mammalian cells. Genomic regions around transcription start sites of expressed sLAD genes display reduced associations with the NL and possess active histone modifications; in contrast, gene bodies of expressed sLAD genes possess very low levels of active histone modifications. Our genome-wide analyses of NL-associated chromatin have enabled functional and mechanistic dissections of gene positioning on transcription regulation. generate DamID maps of genome-NL interaction for mouse 3T3 fibroblasts and C2C12 myoblasts
Project description:Primary objectives: The primary objective is to investigate circulating tumor DNA (ctDNA) via deep sequencing for mutation detection and by whole genome sequencing for copy number analyses before start (baseline) with regorafenib and at defined time points during administration of regorafenib for treatment efficacy in colorectal cancer patients in terms of overall survival (OS).
Primary endpoints: circulating tumor DNA (ctDNA) via deep sequencing for mutation detection and by whole genome sequencing for copy number analyses before start (baseline) with regorafenib and at defined time points during administration of regorafenib for treatment efficacy in colorectal cancer patients in terms of overall survival (OS).
Project description:Comparison between ChIP-Seq data of RAR? and RAR?, between RAR and RXR, as well as between control and retinoic acid-treatment for each investigated nuclear receptors. Mouse were treated by control diet and RA-diet for 1 days. After treatment, livers were used to do ChIP using antibodies of RXR?, RAR?, and RAR?. An aliquote of total chromatin without pull-down process by any antibodies was used as input control. A single-end read of 35bp sequencing was performed on each of ChIPed DNA and input. Sequencing data of RAR? and RAR? were compared to each other. In addtional, each of RAR? and RAR? data were compared with RXR? data. For each nuclear receptor, ChIP-Seq data prior or after RA-treatment were also compared with each other.