Project description:We use NGS to assess the ability of TALE-guided DNA methyltranferases to make targeted changes to DNA methylation Targeted bisulfite sequencing of cells infected with wild-type or mutant TALE-DNMT constructs directed to the CDKN2A (p16) locus
Project description:We applied the solution hybrid selection approach to the enrichment of CpG islands (CGIs) and promoter sequences from the human genome for targeted high-throughput bisulfite sequencing. A single lane of Illumina sequences allowed accurate and quantitative analysis of 1 million CpGs in more than 21,408 CGIs and 15,946 transcriptional regulatory regions. More than 85% of capture probes successfully yielded quantitative DNA methylation information of targeted regions. In this study, we generated genome-wide, single-base resolution DNA methylation maps in three of the most commonly used breast cancer cell lines.Differentially methylated regions (DMRs) were identified in the 5?-end regulatory regions, as well as the intra- and intergenic regions, particularly in the X chromosome among the three cell lines. The single CpG resolution methylation maps of many known tumor suppressor genes were also established in the three cell lines. Here we present a novel approach that combines solution-phase hybrid selection and massively parallel bisulfite sequencing to profile DNA methylation in targeted CGI and promoter regions. We designed 51,466 single strand DNA oligonucleotides (160-mer) which target 23,441 CGIs and the transcription start sites of 19,369 known genes in the human genome. The synthetic long DNA oligonucleotides were converted into biotinylated RNA probes for solution-phase hybridization capture of target DNA. The captured genomic DNA was treated with sodium bisulfite, amplified by PCR and sequenced using Illumina GA IIx sequencer.
Project description:Cytosine methylation of DNA CpG dinucleotides in gene promoters is an epigenetic modification that regulates gene transcription. While many methods exist to interrogate methylation states, no current methods offer large-scale, targeted, single CpG resolution. We report an approach combining bisulfite treatment followed by RainDance microdroplet PCR with next-generation sequencing to assay the methylation state of 50 genes in the regions 1 kb upstream and downstream of their transcription start sites. Wildtype and hypermethylated Jurkat DNA (New Englad Biolabs) was treated with bisulfite to convert all unmethylated cytosines to uracil. Following bisulfite treatment, targeted amplification was carried out using a custom primer library and microdroplet PCR. PCR product was sheared to 200 bp and ligated to sequencing adapters following standard protocols. Sequencing was conducted with single-end 100 bp reads on an Illumina GAIIx for wild type Jurkat DNA or Jurkat CpG DNA with a single sample per lane.
Project description:Due to the large size, complex splicing and wide dynamic range of eukaryotic transcriptomes, RNA sequencing samples the majority of expressed genes infrequently, resulting in sparse sequencing coverage that can hinder robust isoform assembly and quantification. Targeted RNA sequencing addresses this challenge by using oligonucleotide probes to capture selected genes or regions of interest for focused sequencing. This enhanced sequencing coverage confers sensitive gene discovery, robust transcript assembly and accurate gene quantification. Here we describe a detailed protocol for all stages of targeted RNA sequencing, from initial probe design considerations, capture of targeted genes, to final assembly and quantification of captured transcripts. Initial probe design and final analysis can take less than a day, while the central experimental capture stage requires ~7 days. Targetted RNA sequencing of long noncoding RNAs
Project description:We report a method for specific capture of an arbitrary subset of genomic targets for single molecule bisulfite sequencing, and for digital quantitation of DNA methylation at a single nucleotide resolution. We used targeted bisulfite sequencing to characterize the changes of DNA methylation during the de-differentiation of human fibroblasts into hybrid stem cells, and into induced pluripotent stem cells. We compared the methylation level of approximately 66,000 CpG sites within 2020 CpG islands on chromosome 12, chromosome 20, and 34 selected regions. A total of 288 differentially methylated regions were identified between fibroblasts and pluripotent cells. Methylation cluster analysis revealed distinct methylation patterns between fibroblasts and pluripotent cells. Furthermore iPS cells are globally more methylated than human embryonic stem cells, which could be due to the reprogramming process. This targeted bisulfite sequencing method is particularly useful for efficient and large-scale analysis of DNA methylation in organisms with large genomes. Experiment Overall Design: Comparison of DNA methylation on 2020 CpG islands and 34 other selected regions among eleven human ES, iPS and fibroblast lines.
Project description:Due to the large size, complex splicing and wide dynamic range of eukaryotic transcriptomes, RNA sequencing samples the majority of expressed genes infrequently, resulting in sparse sequencing coverage that can hinder robust isoform assembly and quantification. Targeted RNA sequencing addresses this challenge by using oligonucleotide probes to capture selected genes or regions of interest for focused sequencing. This enhanced sequencing coverage confers sensitive gene discovery, robust transcript assembly and accurate gene quantification. Here we describe a detailed protocol for all stages of targeted RNA sequencing, from initial probe design considerations, capture of targeted genes, to final assembly and quantification of captured transcripts. Initial probe design and final analysis can take less than a day, while the central experimental capture stage requires ~7 days.
Project description:We report sequencing of 10 SCC_NodalMet samples from human subjects. Sequencing was done on an oncology targeted gene mutation panel consisting of 76 genes.
Project description:In vertebrates, DNA methylation-mediated repression of retrotransposons is essential for the maintenance of genomic integrity. In the current study, we developed a technique termed HT-TREBS (High-Throughput Targeted Repeat Element Bisulfite Sequencing). This technique is designed to measure the DNA methylation levels of individual loci of any repeat families with next-generation sequencing approaches. To test the feasibility of HT-TREBS, we analyzed the DNA methylation levels of the IAPLTR family using a set of 12 different genomic DNA isolated from the brain, liver and kidney of 4 one-week-old littermates of the mouse strain C57BL/6N. This technique has successfully generated the CpG methylation data of 5,233 loci common in all the samples, representing more than 80% of the individual loci of the five targeted subtypes of the IAPLTR family. According to the results, approximately 5% of the IAPLTR loci have less than 80% average CpG methylation levels with no genomic position preference. Further analyses of the IAPLTR loci also revealed the presence of extensive DNA methylation variations between different tissues and individuals. Overall, these data demonstrate the efficiency and robustness of the new technique, HT-TREBS, and also provide new insights regarding the genome-wide DNA methylation patterns of the IAPLTR repeat elements. High-throughput, single-base resolution, singlicate DNA methylation profiles of IAPLTR retrotransposons in the brain, liver , and kidney of four 1-week-old mouse littemates using the developed technique, HT-TREBS.
Project description:In this work we aim to improve the understanding of the mouse transcriptome complexity, investigate the expressed fraction of the genome and ameliorate the available mouse annotations. We utilized CatureSeq, a recently described strategy meant to enhance the sequencing coverage of low abundant genes. In our experimental design we generated oligonucleotide probes to select annotated and putative long-noncoding RNA and splice junctions. This allowed us to improve dramatically the sequencing throughput of the targeted regions. As a consequence our approach permitted the simultaneous identification of thousands of exons and the expansion of the already known ones The mouse gene assembly is anlaysed by targeted RNA sequencing of lncRNA and splice junctions. 8 mouse tissues and 16 samples are considered in the analysis. Each sample was added with external RNA controls. The controls are polyadenylated transcripts of known concentration designed to be added to an RNA analysis experiment after sample isolation.