Project description:Genome-wide binding of IRF3 was analysed in MM1.S cells using ChIP-seq high-throughput approach. MM1.S cells were fixed in 1% formaldehyde (Alfa Aesar) for 15min at room temperature. cells were lysed with hypotonic lysis buffer for 15minutes followed by nuclear lysis buffer for 15min on ice. ChIP for IRF3 performed by a standard ChIP-seq protocol and the genome-wide binding of IRF3 data was analysed which revealed peaks enrichment at cell cycle genes TSS.
Project description:The nucleosome is a fundamental unit of chromatin in eukaryotes, and generally prevents the binding of transcription factors to genomic DNA. Pioneer transcription factors overcome the nucleosome barrier, and bind their target DNA sequences in chromatin. OCT4 is a representative pioneer transcription factor that plays a role in stem cell pluripotency. In the present study, we biochemically analyzed the nucleosome binding by OCT4. Crosslinking mass spectrometry showed that OCT4 binds the nucleosome.
Project description:This SuperSeries is composed of the SubSeries listed below. In vivo transcription factor binding is regulated by DNA sequence and chromatin features. However, the impact of chromatin context on genome-wide transcription factor binding affinities have not yet been characterized. Here we report the establishment of a quantitative protein-DNA binding assay to determine genome-wide binding affinities to native chromatinized DNA. We use this method to quantify apparent genome-wide binding affinities of both pioneering and non-pioneering transcription factors to uncover the regulatory role of chromatin on transcription factor binding. This revealed that DNA accessibility is the main determinant of transcription factor binding, which restricts nanomolar binding of non-pioneering factors to promoters. DNA binding motifs only appear to be important for very high-affinity binding, but are not essential for nanomolar binding. We uncover numerous biological processes enriched at specific binding affinities, suggesting they are regulated at defined transcription factor concentrations. Importantly, our method adds a new quantitative layer of transcription factor biology, enabling stratification of genomic targets based on transcription factor expression and prediction of transcription factor binding sites under non-physiological conditions, such as disease associated elevated expression of (onco)genes.
Project description:In vivo transcription factor binding is regulated by DNA sequence and chromatin features. However, the impact of chromatin context on genome-wide transcription factor binding affinities have not yet been characterized. Here we report the establishment of a quantitative protein-DNA binding assay to determine genome-wide binding affinities to native chromatinized DNA. We use this method to quantify apparent genome-wide binding affinities of both pioneering and non-pioneering transcription factors to uncover the regulatory role of chromatin on transcription factor binding. This revealed that DNA accessibility is the main determinant of transcription factor binding, which restricts nanomolar binding of non-pioneering factors to promoters. DNA binding motifs only appear to be important for very high-affinity binding, but are not essential for nanomolar binding. We uncover numerous biological processes enriched at specific binding affinities, suggesting they are regulated at defined transcription factor concentrations. Importantly, our method adds a new quantitative layer of transcription factor biology, enabling stratification of genomic targets based on transcription factor expression and prediction of transcription factor binding sites under non-physiological conditions, such as disease associated elevated expression of (onco)genes.
Project description:In vivo transcription factor binding is regulated by DNA sequence and chromatin features. However, the impact of chromatin context on genome-wide transcription factor binding affinities have not yet been characterized. Here we report the establishment of a quantitative protein-DNA binding assay to determine genome-wide binding affinities to native chromatinized DNA. We use this method to quantify apparent genome-wide binding affinities of both pioneering and non-pioneering transcription factors to uncover the regulatory role of chromatin on transcription factor binding. This revealed that DNA accessibility is the main determinant of transcription factor binding, which restricts nanomolar binding of non-pioneering factors to promoters. DNA binding motifs only appear to be important for very high-affinity binding, but are not essential for nanomolar binding. We uncover numerous biological processes enriched at specific binding affinities, suggesting they are regulated at defined transcription factor concentrations. Importantly, our method adds a new quantitative layer of transcription factor biology, enabling stratification of genomic targets based on transcription factor expression and prediction of transcription factor binding sites under non-physiological conditions, such as disease associated elevated expression of (onco)genes.
Project description:Flag-taged IRF3-binding RNAs were analyzed by imprinting RNA-sequencing of anti-flag antibody-retrieved complexes from macrophages lysate.
Project description:IRF3 is one of the most critical transcription factor in down stream of pattern recognition receptors (such as toll-like receptor and RIG-I-like receptor) signalling pathway. IRF3 is known to induce the expression of type I IFN gene upon virus infection. To furter examine the role of IRF3 in virus-induced gene expression, we preformed microarray analysis in IRF3-/- peritoneal macrophages infected with VSV, and found that IRF3 suppresses the expression of Il12b gene. Peritoneal macrophages from WT of IRF3-/- B6 mice were infected with VSV(1 M.O.I. ) for 6 hous, and then subjected to microarray analysis.