Project description:Epigenetic control is an important aspect of gene regulation. Despite detailed understanding of many examples, the transcription of non-coding RNA genes by RNA polymerase (pol) III is less well characterized. Here we profile the epigenetic features of pol III target genes throughout the human genome. This reveals that the chromatin landscape of pol III-transcribed genes resembles that of pol II templates in many ways, although there are also clear differences. Our analysis also discovered an entirely unexpected phenomenon, namely that pol II co-localizes with the majority of genomic loci that are bound by pol III.
Project description:Epigenetic control is an important aspect of gene regulation. Despite detailed understanding of many examples, the transcription of non-coding RNA genes by RNA polymerase (pol) III is less well characterized. Here we profile the epigenetic features of pol III target genes throughout the human genome. This reveals that the chromatin landscape of pol III-transcribed genes resembles that of pol II templates in many ways, although there are also clear differences. Our analysis also discovered an entirely unexpected phenomenon, namely that pol II co-localizes with the majority of genomic loci that are bound by pol III.
Project description:Epigenetic control is an important aspect of gene regulation. Despite detailed understanding of many examples, the transcription of non-coding RNA genes by RNA polymerase (pol) III is less well characterized. Here we profile the epigenetic features of pol III target genes throughout the human genome. This reveals that the chromatin landscape of pol III-transcribed genes resembles that of pol II templates in many ways, although there are also clear differences. Our analysis also discovered an entirely unexpected phenomenon, namely that pol II co-localizes with the majority of genomic loci that are bound by pol III. Chip-Seq experiments for six samples: Pol III, TFIIIB, TFIIIC, H3K4me3 in HeLa cells and Pol III, S2 phos Pol II in CD4+ cells.
Project description:Epigenetic control is an important aspect of gene regulation. Despite detailed understanding of many examples, the transcription of non-coding RNA genes by RNA polymerase (pol) III is less well characterized. Here we profile the epigenetic features of pol III target genes throughout the human genome. This reveals that the chromatin landscape of pol III-transcribed genes resembles that of pol II templates in many ways, although there are also clear differences. Our analysis also discovered an entirely unexpected phenomenon, namely that pol II co-localizes with the majority of genomic loci that are bound by pol III. RNA-seq experiment for total RNA in CD4+ cells.
Project description:MAF1 represses Pol III-mediated transcription by interfering with TFIIIB and Pol III. Herein, we found that MAF1 knockdown induced CDKN1A transcription and chromatin looping concurrently with Pol III recruitment. Simultaneous knockdown of MAF1 with Pol III or BRF1 (subunit of TFIIIB) diminished the activation and looping effect, which indicates that recruiting Pol III was required for activation of Pol II-mediated transcription and chromatin looping. ChIP analysis after MAF1 knockdown indicated enhanced binding of Pol III and BRF1, as well as of CFP1, p300, and PCAF, which are factors that mediate active histone marks, along with the binding of TBP and POLR2E to the CDKN1A promoter. Simultaneous knockdown with Pol III abolished these regulatory events. Similar results were obtained for GDF15. Our results reveal a novel mechanism by which MAF1 and Pol III regulate the activity of a protein-coding gene transcribed by Pol II.
Project description:Asf1, through its histone chaperone activity, helps chromatin closing/opening during DNA replication, repair, recombination and transcription. Despite extensive research on Asf1-mediated physiological functions, a genome-wide localization map is lacking, limiting our knowledge of chromosomal features targeted by Asf1. We present a high-resolution genome-wide map of Asf1, localizing at essentially all pol III-transcribed genes, highly active pol II-transcribed genes and heterochromatic features. Pol III-transcribed genes are negatively regulated by Asf1, whereas pol II genes are regulated indirectly by Asf1-dependent H3K56 acetylation. Interestingly, Asf1 localization along yeast chromosomes shows nearly identical distribution to that of the condensin complex, predicting a functional overlap in chromosome architecture and genome organization.
Project description:MAF1 represses Pol III-mediated transcription by interfering with TFIIIB and Pol III. Herein, we found that MAF1 knockdown induced CDKN1A transcription and chromatin looping concurrently with Pol III recruitment. Simultaneous knockdown of MAF1 with Pol III or BRF1 (subunit of TFIIIB) diminished the activation and looping effect, which indicates that recruiting Pol III was required for activation of Pol II-mediated transcription and chromatin looping. ChIP analysis after MAF1 knockdown indicated enhanced binding of Pol III and BRF1, as well as of CFP1, p300, and PCAF, which are factors that mediate active histone marks, along with the binding of TBP and POLR2E to the CDKN1A promoter. Simultaneous knockdown with Pol III abolished these regulatory events. Similar results were obtained for GDF15. Our results reveal a novel mechanism by which MAF1 and Pol III regulate the activity of a protein-coding gene transcribed by Pol II. Knockdown assay was performed using siRNA obtained from MISSION®RNA (Sigma). Inhibition of expression of Pol III (SASI_Hs01_00046568) and MAF1 (SASI_Hs01_00135954) was achieved by transfection with LipofectamineTM RNAiMax (Invitrogen) according to the manufacturer’s protocol. MISSION® siRNA Universal Negative Control (Sigma) was used as knockdown control. Cells were transfected in serum-free medium. After 8 h, the siRNA containing medium was replaced with complete medium.
Project description:Inflammation is associated with many cardiovascular pathologies, but the underlying mechanisms remain unclear. To explore this in more detail, we characterized the transcriptome of an immortalized adult human ventricular cardiomyocyte cell line (AC16) in response to tumor necrosis factor (TNFa). Using a combination of genomic approaches, including global nuclear run-on sequencing (GRO-seq) and chromatin immunoprecipitation coupled with sequencing (ChIP-seq), we identified ~30,000 transcribed regions in AC16 cells, which includes a set of RNA polymerases I and III (Pol I and Pol III) transcribed regions revealed in the presence of M-NM-1-amanitin. The set of transcribed regions produces both protein-coding and non-coding RNAs, many of which have not been annotated previously, including enhancer RNAs originating from NF-M-NM-:B binding sites. In addition, we observed that AC16 cells rapidly and dynamically reorganize their transcriptomes in response to TNFa stimulation in an NF-M-NM-:B-dependent manner, switching from a basal state to a proinflammatory state affecting a spectrum of cardiac-associated protein-coding and non-coding genes. Moreover, we observed distinct Pol II dynamics for up- and downregulated genes, with a rapid release of Pol II into productive elongation for TNFa-stimulated genes. Our studies shed new light on the regulation of the cardiomyocyte transcriptome in response to a proinflammatory signal and help to clarify the link between inflammation and cardiomyocyte function at the transcriptional level. Using GRO-seq and ChIP-seq (p65 and RNA Pol II) over a time course of TNFM-NM-1 signaling in AC16 human cardiomyocytes.