Project description:We aimed to discover trans-acting RNA molecules involved in mRNA 3 processing. We reasoned that, if there exist such functional RNAs, they must directly associate with the key machinery responsible for mRNA 3 processing. Therefore, it would be of great value to comprehensively identify RNAs interacting with pre-mRNA 3 processing complex. To this goal, we took advantage of previously well-characterized system combined with high-throughput sequencing to investigate the target RNAs at the transcriptomic level. Fip1 protein is an essential mRNA 3' processing factor. Our in vitro data suggested that snoRD50a affects Fip1/RNA interaction in SV40 late (SVL) polyA site 3' processing. To determine whether snoRD50a influences Fip1/RNA interaction at transcriptomic level in vitro, we performed Fip1 iCLIP-seq experiments in Hela cells transfected with control NC ASO (negative control anti-sense DNA) or snoRD50a ASO.
Project description:This data was generated by ENCODE. If you have questions about the data, contact the submitting laboratory directly (Yijun Ruan mailto:ruanyj@gis.a-star.edu.sg). If you have questions about the Genome Browser track associated with this data, contact ENCODE (mailto:genome@soe.ucsc.edu). This track was produced as part of the ENCODE Project. It shows the locations of protein factor mediated chromatin interactions determined by Chromatin Interaction Analysis with Paired-End Tag (ChIA-PET) data (Fullwood et al., 2010) extracted from five different human cancer cell lines (K562 (chronic myeloid leukemia), HCT116 (colorectal cancer), HeLa-S3 (cervical cancer), MCF-7 (breast cancer), and NB4 (promyelocytic)). A chromatin interaction is defined as the association of two regions of the genome that are far apart in terms of genomic distance, but are spatially proximate to each other in the 3-dimensional cellular nucleus. Additionally, ChIA-PET experiments generate transcription factor binding sites. A binding site is defined as a region of the genome that is highly enriched by specific Chromatin ImmunoPrecipitation (ChIP) against a transcription factor, which indicates that the transcription factor binds specifically to this region. The protein factors displayed in the track include estrogen receptor alpha (ERa), RNA polymerase II (RNAPII), and CCCTC binding factor (CTCF). For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf Chromatin interaction analysis with paired-end tag sequencing (ChIA-PET) is a global de novo high-throughput method for characterizing the 3-dimensional structure of chromatin in the nucleus. In the ChIA-PET protocol, samples were cross-linked and fragmented, then subjected to chromatin immunoprecipitation. The DNA fragments that were brought together by the chromatin interactions were then proximity-ligated. During this proximity-ligation step, the half-linkers (created by the fragmentation) containing flanking MmeI sites (type IIS restriction enzymes) were first ligated to the DNA fragments and then ligated to each other to form full linkers. Full linkers bridge either two ends of a self-circularized fragment, or two ends of two different chromatin fragments. The material was then reverse cross-linked, purified and digested with MmeI. MmeI cuts 20 base pairs away from its recognition site. Tag-linker-tag (paired-end tag, PET) constructs were sequenced by ultra-high-throughput methods (Illumina or SOLiD paired-end sequencing). ChIA-PET reads were processed with the ChIA-PET Tool (Li et al., 2010) by the following steps: linker filtering, short reads mapping, PET classification, binding site identification, and interaction cluster identification. The high-confidence binding sites and chromatin interaction clusters were reported. Chromatin interactions identified by ChIA-PET have been validated by 3C, ChIP-3C, 4C and DNA-FISH (Fullwood et al., 2009).
Project description:ChIP-Seq, which combines chromatin immunoprecipitation (ChIP) with high-throughput massively parallel sequencing, is increasingly being used for identification of proteinM-bM-^@M-^SDNA interactions in-vivo in the genome. In general, current algorithms for ChIP-seq reads employ artificial estimation of the average length of DNA fragments for peak finding, leading to uncertain prediction of DNA-protein binding sites. Here, we present SIPeS (Site Identification from Paired-end Sequencing), a novel algorithm for precise identification of binding sites from short reads generated from paired-end Solexa ChIP-Seq technology. SIPeS uses a dynamic baseline directly via M-bM-^@M-^Xpiling upM-bM-^@M-^Y the corresponding fragments defined by the paired reads to efficiently find peaks corresponding to binding sites. The performance of SIPeS is demonstrated by analyzing the ChIP-Seq data of the Arabidopsis basic helix-loop-helix transcription factor ABORTED MICROSPORES (AMS). The robustness of SIPeS was demonstrated in higher sensitivity and spatial resolution in peak finding compared to three existing peak detection algorithms. Keywords: transcription factors (protein-DNA interactions) Examination of protein-DNA interactions in buds of Arabidopsis anther cell
Project description:ChIP-Seq, which combines chromatin immunoprecipitation (ChIP) with high-throughput massively parallel sequencing, is increasingly being used for identification of protein–DNA interactions in-vivo in the genome. In general, current algorithms for ChIP-seq reads employ artificial estimation of the average length of DNA fragments for peak finding, leading to uncertain prediction of DNA-protein binding sites. Here, we present SIPeS (Site Identification from Paired-end Sequencing), a novel algorithm for precise identification of binding sites from short reads generated from paired-end Solexa ChIP-Seq technology. SIPeS uses a dynamic baseline directly via ‘piling up’ the corresponding fragments defined by the paired reads to efficiently find peaks corresponding to binding sites. The performance of SIPeS is demonstrated by analyzing the ChIP-Seq data of the Arabidopsis basic helix-loop-helix transcription factor ABORTED MICROSPORES (AMS). The robustness of SIPeS was demonstrated in higher sensitivity and spatial resolution in peak finding compared to three existing peak detection algorithms. Keywords: transcription factors (protein-DNA interactions)
Project description:Spliced messages constitute one-fourth of expressed mRNAs in the yeast Saccharomyces cerevisiae, and most mRNAs in metazoans. Splicing requires 5' splice site (5'SS), branch point (BP), and 3' splice site (3'SS) elements, but the role of the BP in splicing control is poorly understood because BP identification remains difficult. We developed a high-throughput method, Branch-seq, to map BP and 5'SS of isolated RNA lariats. Applied to S. cerevisiae, Branch-seq detected 76% of expressed, annotated BPs and identified a comparable number of novel BPs. We used RNA-seq to confirm associated 3'SS locations, identifying some 200 novel splice junctions, including an AT-AC intron. We show that several yeast introns use two or even three different BPs, with effects on 3'SS choice, protein coding potential, or RNA stability and identify novel introns whose splicing changes during meiosis or in response to stress. Together, these findings reveal BP-based regulation and demonstrate unanticipated complexity of splicing in yeast. 1 Lariat-seq experiment library. 3 barcoded Branch-seq libraries that make up one experiment. 26 RNA-seq samples, 2 biological replicates of each.