Analysis of alternative cleavage and polyadenylation by 3' region extraction and deep sequencing
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE42398 | GEO | 2012/12/17
SECONDARY ACCESSION(S): PRJNA181289
REPOSITORIES: GEO
Similar Datasets
Project description:Alternative cleavage and polyadenylation (APA) generates diverse mRNA isoforms. We developed 3' region extraction and deep sequencing (3'READS) to address mispriming issues that commonly plague poly(A) site (pA) identification, and we used the method to comprehensively map pAs in the mouse genome. Thorough annotation of gene 3' ends revealed over 5,000 previously overlooked pAs (~8% of total) flanked by A-rich sequences, underscoring the necessity of using an accurate tool for pA mapping. About 79% of mRNA genes and 66% of long noncoding RNA genes undergo APA, but these two gene types have distinct usage patterns for pAs in introns and upstream exons. Quantitative analysis of APA isoforms by 3'READS indicated that promoter-distal pAs, regardless of intron or exon locations, become more abundant during embryonic development and cell differentiation and that upregulated isoforms have stronger pAs, suggesting global modulation of the 3' endM-bM-^@M-^Sprocessing activity in development and differentiation. 3'READS to map pAs in mouse genome
2012-12-17 | E-GEOD-42398 | biostudies-arrayexpress
Project description:Sequencing of the 3â end of poly(A)+ RNA identifies cleavage and polyadenylation sites (pAs) and measures transcript expression. We previously developed a method, 3â region extraction and deep sequencing (3âREADS), to address mispriming issues that often plague 3â end sequencing. Here we report a new version, named 3âREADS+, which has vastly improved accuracy and sensitivity. Using a special locked nucleic acid oligo to capture poly(A)+ RNA and to remove bulk of the poly(A) tail, 3âREADS+ generates RNA fragments with an optimal number of terminal As that balance data quality and detection of genuine pAs. With improved RNA ligation steps for efficiency, the method shows much higher sensitivity (over two orders of magnitude) compared to the previous version. Using 3âREADS+, we have uncovered a sizable fraction of previously overlooked pAs located next to or within a stretch of adenylate residues in human genes, and more accurately assessed the frequency of alternative cleavage and polyadenylation (APA) in HeLa cells (~50%). 3âREADS+ will be a useful tool to accurately study APA and to analyze gene expression by 3â end counting, especially when the amount of input total RNA is limited. Nine 3'READS+ libraries were made with different amounts (100 ng, 200 ng, 400 ng, 1000 ng, 5000 ng, 15000 ng) of input Hela RNA.
2016-08-14 | E-GEOD-84170 | biostudies-arrayexpress
Project description:Sequencing of the 3’ end of poly(A)+ RNA identifies cleavage and polyadenylation sites (pAs) and measures transcript expression. We previously developed a method, 3’ region extraction and deep sequencing (3’READS), to address mispriming issues that often plague 3’ end sequencing. Here we report a new version, named 3’READS+, which has vastly improved accuracy and sensitivity. Using a special locked nucleic acid oligo to capture poly(A)+ RNA and to remove bulk of the poly(A) tail, 3’READS+ generates RNA fragments with an optimal number of terminal As that balance data quality and detection of genuine pAs. With improved RNA ligation steps for efficiency, the method shows much higher sensitivity (over two orders of magnitude) compared to the previous version. Using 3’READS+, we have uncovered a sizable fraction of previously overlooked pAs located next to or within a stretch of adenylate residues in human genes, and more accurately assessed the frequency of alternative cleavage and polyadenylation (APA) in HeLa cells (~50%). 3’READS+ will be a useful tool to accurately study APA and to analyze gene expression by 3’ end counting, especially when the amount of input total RNA is limited.
2016-08-14 | GSE84170 | GEO
Project description:Cleavage and polyadenylation is essential for 3’ end processing of almost all eukaryotic mRNAs. Recent studies have shown widespread alternative cleavage and polyadenylation (APA) events leading to mRNA isoforms with different 3’UTRs and/or coding sequences. Here we present a compendium of conserved cleavage and polyadenylation sites (PASs) in mammalian genes, based on ~1.2 billion 3’ end sequencing reads from over 360 human, mouse and rat samples. We show that ~80% of mammalian mRNA genes contain at least one conserved PAS, and ~50% have conserved APA events. PAS conservation generally reduces promiscuous 3’ end processing, stabling gene expression levels across species. Conservation of APA correlates with gene age, gene expression features, and gene functions. Genes with certain functions, such as cell morphology, cell proliferation, and mRNA metabolism, are particularly enriched with APA events. While tissue-specific genes typically have a low APA rate, brain-specific genes tend to evolve APA. We show enrichment of mRNA destabilizing motifs in alternative 3’UTR sequences, leading to substantial differences in mRNA stability between 3’UTR APA isoforms. Using conserved PASs, we reveal sequence motifs surrounding APA sites and a preference of adenosine at the cleavage site. Mutations of the U-rich motif around the PAS often accompany APA profile changes between species. Analysis of lncRNA PASs indicates a mechanism of PAS fixation involving evolution of A-rich motifs. Taken together, our results present a comprehensive view of PAS evolution in mammals, and a phylogenic understanding of APA functions.
2018-08-08 | GSE111134 | GEO
Project description:Most eukaryotic genes harbor multiple cleavage and polyadenylation sites (PASs), leading to expression of alternative polyadenylation (APA) isoforms. APA regulation has been implicated in a diverse array of physiological and pathological conditions. While RNA sequencing tools that generate reads containing the PAS, named onSite reads, have been instrumental in identifying PASs, they have not been widely used. By contrast, a growing number of methods generate reads that are close to the PAS, named nearSite reads, including the 3’ end counting strategy commonly used in single cell analysis. How these nearSite reads can be used for APA analysis, however, is poorly studied. Here, we present a computational method, named model-based analysis of alternative polyadenylation using 3’ end-linked reads (MAAPER), to examine APA using nearSite reads. MAAPER uses a probabilistic model to predict PASs for nearSite reads with high accuracy and sensitivity, and examines different types of APA events, including those in 3’UTRs and introns, with robust statistics. We show usability of MAAPER with data from bulk RNA and single cell samples. Our result also highlights the importance of using well annotated PASs for nearSite read analysis.
2021-01-17 | GSE164958 | GEO
Project description:Alternative polyadenylation (APA) of mRNAs has emerged as an important mechanism for post-transcriptional gene regulation in higher eukaryotes. Although microarrays have recently been used to characterize APA globally, they have a number of serious limitations that prevents comprehensive and highly quantitative analysis. To better characterize APA and its regulation, we have developed a deep sequencing-based method called Poly(A) Site Sequencing (PAS-Seq) for quantitatively profiling RNA polyadenylation at the transcriptome level. PAS-Seq not only accurately and comprehensively identifies poly(A) junctions in mRNAs and noncoding RNAs, but also provides quantitative information on the relative abundance of polyadenylated RNAs. We first analyzed HeLa cell transcriptome using PAS-Seq to demonstrate that PAS-Seq not only accurately and comprehensively identifies poly(A) junctions, but also provide quantitative information on the relativel abundance of APA isoforms. Next we analyzed the mouse embryonic stem cells, neural stem/progenitor cells, and neurons by PAS-Seq to characterize the dynamic changes of mRNA polyadenylation during stem cell differentiation.
2011-02-26 | E-GEOD-25450 | biostudies-arrayexpress
Project description:Alternative cleavage and polyadenylation (APA) results in mRNA isoforms containing different 3’ untranslated regions (3’UTRs) and/or coding sequences. How core cleavage and polyadenylation (C/P) factors regulate APA is not well understood. Using siRNA knockdown coupled with deep sequencing, we found that several C/P factors can play significant roles in 3’UTR-APA. Whereas Pcf11 and Fip1 enhance usage of proximal poly(A) sites (pAs), CFI-25/68, PABPN1, and PABPC1 promote usage of distal pAs. Strong cis element biases were found for pAs regulated by CFI or Fip1, and the distance between pAs plays an important role in APA regulation. In addition, intronic pAs are substantially regulated by splicing factors, with U1 mostly influencing C/P events in 5’ introns and U2 impacting those in efficiently spliced introns. Furthermore, PABPN1 regulates expression of transcripts with pAs near the transcription start site, a property possibly related to its role in RNA degradation. Finally, we found that groups of APA events regulated by C/P factors are also modulated in cell differentiation and development with distinct trends. Together, our results indicate that the abundance of different C/P factors and splicing factors plays diverse roles in APA, and is relevant to APA regulation in biological conditions. knockdown experiments of 23 C/P factors, 3 splicing factors and U1D in mouse C2C12 myoblast cells
2015-04-01 | E-GEOD-62001 | biostudies-arrayexpress
Project description:Alternative cleavage and polyadenylation (APA) results in mRNA isoforms containing different 3’ untranslated regions (3’UTRs) and/or coding sequences. How core cleavage and polyadenylation (C/P) factors regulate APA is not well understood. Using siRNA knockdown coupled with deep sequencing, we found that several C/P factors can play significant roles in 3’UTR-APA. Whereas Pcf11 and Fip1 enhance usage of proximal poly(A) sites (pAs), CFI-25/68, PABPN1, and PABPC1 promote usage of distal pAs. Strong cis element biases were found for pAs regulated by CFI or Fip1, and the distance between pAs plays an important role in APA regulation. In addition, intronic pAs are substantially regulated by splicing factors, with U1 mostly influencing C/P events in 5’ introns and U2 impacting those in efficiently spliced introns. Furthermore, PABPN1 regulates expression of transcripts with pAs near the transcription start site, a property possibly related to its role in RNA degradation. Finally, we found that groups of APA events regulated by C/P factors are also modulated in cell differentiation and development with distinct trends. Together, our results indicate that the abundance of different C/P factors and splicing factors plays diverse roles in APA, and is relevant to APA regulation in biological conditions.
2015-04-01 | GSE62001 | GEO
Project description:Polyadenylation of nascent RNA by poly(A) polymerase (PAP) is important for 3’ end maturation of almost all eukaryotic mRNAs. Most mammalian genes harbor multiple polyadenylation sites (PASs), leading to expression of alternative polyadenylation (APA) isoforms with distinct functions. How poly(A) polymerases may regulate PAS usage and hence gene expression is poorly understood. Here we show that the nuclear canonical (PAPalpha and PAPgamma) and non-canonical (Star-PAP) PAPs play diverse roles in PAS selection and gene expression. Deficiencies in the PAPs resulted in perturbations of gene expression, with Star-PAP impacting lowly expressed mRNAs and long-noncoding RNAs to the greatest extent. Importantly, different PASs of a gene are distinctly regulated by different PAPs, leading to widespread relative expression changes of APA isoforms. The location and surrounding sequence motifs of a PAS appear to differentiate its regulation by the PAPs. We show Star-PAP-specific PAS usage regulates the expression of the eukaryotic translation initiation factor EIF4A1, the tumor suppressor gene PTEN, and the long non-coding RNA NEAT1. The Star-PAP-mediated APA of PTEN is essential for DNA damage-induced increase of PTEN protein levels. Together, our results reveal a PAS-guided and PAP-mediated paradigm for gene expression in response to cellular signaling cues.
2017-06-19 | GSE84461 | GEO
Project description:Alternative cleavage and polyadenylation (APA) is a mechanism generating multiple mRNA isoforms with different 3'UTRs and/or coding sequences from a single gene. Here we used 3' Region Extraction And Deep Sequencing (3'READS) to systematically map cleavage and polyadenylation sites (PAS) in Drosophila and analyzsed APA in the RpII215 C4 mutant strain, which harbors a mutant RNA polymerase II (RNAPII) with a slower elongation rate. We found that about two thirds of mRNA genes in fly undergo APA and cis element analysis indicates that fly PASs are associated with downstream UGUG elements to a lesser degree than mammalian PASs. The head tissue tends to use distal PASs compared to the body, leading to preferential expression of long 3'UTR isoforms and transcripts using distal terminal exons. Gene Ontology analysis correlates brain-specific APA events with neuronal functions, indicating their functional relevance. We also found that the distance between the proximal and distal PASs and intron locations might play important roles for brain APA. Analysis of the RpII215 C4 mutant strain, reveals that a 50% decrease in transcriptional elongation rate leads to shortened 3'UTRs in the fly body, but not in the head. This correlates with an upregulation of Ssu72 specifically in RpII215 C4 bodies, suggesting that the mechanism underlying those observations involves another layer of regulation by RNAPII termination factors. By contrast, more significant activation of intronic PASs was observed in the head compared to the body when RNAPII speed is slow. Together, our results reveal that in Drosophila RNAPII elongation impacts on PAS choice in a context-specific manner.
2017-08-23 | GSE85368 | GEO