Project description:We investigated the association between genetic variants in the histone modification regions and the prognosis of lung adenocarcinoma after curative surgery. Potentially functional SNPs were selected using integrated analysis of ChIP-seq and RNA-seq. The SNPs were analyzed in a discovery set (n=166) and a validation set (n=238). The associations of the SNPs with overall survival (OS) and disease-free survival (DFS) were analyzed. This study showed that genetic variants in the histone modification regions could predict the prognosis of lung adenocarcinoma after surgery.
Project description:We report the application of single-molecule-based sequencing technology for high-throughput profiling of histone modifications in mammalian cells. By obtaining over four billion bases of sequence from chromatin immunoprecipitated DNA, we generated genome-wide chromatin-state maps of mouse embryonic stem cells, neural progenitor cells and embryonic fibroblasts. We find that lysine 4 and lysine 27 trimethylation effectively discriminates genes that are expressed, poised for expression, or stably repressed, and therefore reflect cell state and lineage potential. Lysine 36 trimethylation marks primary coding and non-coding transcripts, facilitating gene annotation. Trimethylation of lysine 9 and lysine 20 is detected at satellite, telomeric and active long-terminal repeats, and can spread into proximal unique sequences. Lysine 4 and lysine 9 trimethylation marks imprinting control regions. Finally, we show that chromatin state can be read in an allele-specific manner by using single nucleotide polymorphisms. This study provides a framework for the application of comprehensive chromatin profiling towards characterization of diverse mammalian cell populations.
Project description:We report the application of Chromatin immunoprecipitation sequencing technology for p300 protein in PBS- or bleomycin-treated lung of mice.
Project description:H2B mono-ubiquitylation is required for multiple methylations of both H3K4 and H3K79 and has been implicated in gene expression from yeast to human. However, molecular crosstalk between H2BUb1 and other modifications, especially H3K4 and H3K79 methylations, remains unclear in vertebrates. To understand the functional role of H2BUb1, genome-wide histone modification patterns were measured in human cells. This study proposes dual roles of H2BUb1 that are both H3 methylation dependent and independent. First, H2BUb1 is a 5'-enriched active transcription mark and is co-occupied with H3K79 methylations in actively transcribed regions. Importantly, this study found a unique role of H2BUb1 in chromatin architecture independent of histone H3 methylations. H2BUb1 is well positioned in exon-intron boundaries of highly expressed exons and is specifically enriched in 5'-biased exons. Furthermore, H2BUb1 demonstrates increased occupancy in skipped exons compared to flanking exons for the human and mouse genome. Our findings suggest that a potentiating mechanism links H2BUb1 to both H3K79 methylations in actively transcribed regions and the exon-intron structure of highly expressed exons through the regulation of nucleosome dynamics during transcription elongation. We generated high-throughput sequencing (ChIP-seq) data for genome-wide occupancy of H2BUb1, nucleosome, H3K4me3, H3K36me3, H379me1/2/3, H3Ac, and mRNA in human embryonic carcinoma cells. We performed ChIP-seq for seven different histone modifications, MNase-seq, mRNA-seq (two replications), and inputDNA-seq in NCCIT cell lines (human embryonic carcinoma cell lines). We also performed mRNA-seq for RNF20-siRNA transfected NCCIT cells, where H2BUb1 signals decreased.
Project description:LncRNAs have emerged as a novel class of critical regulators of cancer. We aimed to construct a landscape of lncRNAs and their potential target genes in lung adenocarcinoma. Genome-wide expression of lncRNAs and mRNAs was determined using microarray. qRT-PCR was performed to validate the expression of the selected lncRNAs in a cohort of 42 tumor tissues and adjacent normal tissues. R and Bioconductor were used for data analysis. A total of 3045 lncRNAs were differentially expressed between the paired tumor and normal tissues (1048 up and 1997 down). Meanwhile, our data showed that the expression NONHSAT077036 was associated with N classification and clinical stage. Further, we analyzed the potential co-regulatory relationship between the lncRNAs and their potential target genes using the 'cis' and 'trans' models. In the 25 related transcription factors (TFs), our analysis of The Cancer Genome Atlas database (TCGA) found that patients with lower expression of POU2F2 and higher expression of TRIM28 had a shorter overall survival time. The POU2F2 and TRIM28 co-expressed lncRNA landscape characterized here may shed light into normal biology and lung adenocarcinoma pathogenesis, and be valuable for discovery of biomarkers.
Project description:We generated genome-wide chromatin state and RNA Polymerase II binding maps in mouse erythroid cells by ChIP-Seq. Examination of 4 different histone modifications (H3K4me3, H3K4me1, H3K27me3, H3K27ac) and RNA Polymerase II (RNAP2) binding in mouse erythroid cells (Ter119+).
Project description:The HIRA chaperone complex, comprised of HIRA, UBN1 and CABIN1, collaborates with histone-binding protein ASF1a to incorporate histone variant H3.3 into chromatin in a DNA replication-independent manner. To better understand its function and mechanism, we integrated HIRA, UBN1, ASF1a and histone H3.3 ChIP-seq and gene expression analyses. Most HIRA-binding sites co-localize with UBN1, ASF1a and H3.3 at active promoters and active and weak/poised enhancers. At promoters, binding of HIRA/UBN1/ASF1a correlates with the level of gene expression. HIRA is required for deposition of histone H3.3 at its binding sites. There are marked differences in nucleosome and co-regulator composition at different classes of HIRA-bound regulatory site. Underscoring this, we report novel physical interactions between the HIRA complex and transcription factors, a chromatin insulator and an ATP-dependent chromatin-remodelling complex. Our results map the distribution of the HIRA chaperone across the chromatin landscape and point to different interacting partners at functionally distinct regulatory sites. Examination of H3.3 histone modification in HeLA cells with accompanying FAIRE data