Long-read sequencing reveals transposable element-derived chimeric transcripts at zygotic genome activation in mammalian embryos
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ABSTRACT:
ORGANISM(S): Mus musculus Bos taurus
PROVIDER: GSE337003 | GEO | 2026/07/10
REPOSITORIES: GEO
Similar Datasets
Project description:We have used the genetic resources of Arabidopsis thaliana to generate mutant lines that have reactivated TE expression. We used these lines with long-read Oxford Nanopore sequencing technology to capture Transposable Element (TE) mRNAs for TE transcript annotation.
2020-07-17 | GSE145066 | GEO
Project description:Background: Eukaryotic organisms have evolved a series of mechanisms to regulate transposable element (TE) expression based on RNA silencing. In plants, the initial step in the recognition of TE transcripts relies on microRNAs, but this is unlikely to take place in the pollen grain where natural reactivation of TE transcription occurs but microRNAs accumulate to low levels. We investigated small non-coding RNA accumulation in plants and found conserved tRNA-derived RNA fragment (tRF) accumulation in the pollen grain or analogous reproductive structure in a variety of plant species. Results:Analysis of tRF biology in Arabidopsis revealed that tRFs are regulated by the chromatin modifier DDM1, have a microRNA-like biogenesis pathway, and specifically target TE mRNAs. In addition, we provide evidence that tRF targeting is involved in the production of secondary small RNAs derived from TE transcripts, which initiate a cascade of RNAi and TE silencing. Conclusion:that tRFs are bona-fide regulatory microRNA-like small RNAs involved in the regulation of genome stability through the targeting of TE transcripts.
2017-02-23 | GSE63879 | GEO
Project description:Investigation of the effect of the knockdown of AT-hook motif DNA binding nuclear matrix protein TRANSPOSABLE ELEMENT KILLER (TEK) in the Arabidopsis Landsberg erecta (Ler) background Transposable elements (TEs) are silenced by epigenetic mechanisms of DNA and histone methylation. The repressive histone modification H3 lysine 9 dimethylation (H3K9me2) is TE-associated epigenetic hallmark, and is necessary for DNA methylation. However the mechanism to direct the repressive epigenetic modification in TEs has remained elusive. Here we show that knockdown of the AT-hook motif DNA binding nuclear matrix protein TRANSPOSABLE ELEMENT KILLER (TEK) in the Arabidopsis Landsberg erecta (Ler) background results in robust activation of various TEs, the repeat-containing floral repressor gene FWA and the TE-containing floral repressor FLOWERING LOCUS C (FLC). A four chip study using two separate wild-type seedling mRNA samples and two separate TEKi seedling mRNA samples
2012-09-12 | E-GEOD-39158 | biostudies-arrayexpress
Project description:Long-read sequencing reveals transposable element-derived chimeric transcripts at zygotic genome activation in mammalian embryos
| PRJNA1483693 | ENA
Project description:Genomes constantly face threats from transposable elements (TEs) and other genomic parasites. While the silencing of existing TE has been well studied, little is known about how cells recognize new invading TEs that they have not previously encountered. Here we explore this question by inserting a foreign sequences into S. pombe. Our data revealed that the newly invading TE tj1 is recognized and targeted for silencing by RNAi and heterochromatin. The efficiency of recognition, as well as the degree and stability of silencing, depends on the copy number and insertion location of the TE. We demonstrated that RNA, rather than DNA, is sensed, and that the efficiency of TE recognition correlates with levels of RNA antisense to the TE, generated from upstream transcripts. We also show that various genes of non-transposable nature can initiate silencing. Our data show that silencing may not require recognition of specific elements in the transposon by the host defense systems, and suggest that disruption of host transcription patterns can trigger recognition of TE.
2026-04-16 | GSE249616 | GEO
Project description:Investigation of the effect of the knockdown of AT-hook motif DNA binding nuclear matrix protein TRANSPOSABLE ELEMENT KILLER (TEK) in the Arabidopsis Landsberg erecta (Ler) background Transposable elements (TEs) are silenced by epigenetic mechanisms of DNA and histone methylation. The repressive histone modification H3 lysine 9 dimethylation (H3K9me2) is TE-associated epigenetic hallmark, and is necessary for DNA methylation. However the mechanism to direct the repressive epigenetic modification in TEs has remained elusive. Here we show that knockdown of the AT-hook motif DNA binding nuclear matrix protein TRANSPOSABLE ELEMENT KILLER (TEK) in the Arabidopsis Landsberg erecta (Ler) background results in robust activation of various TEs, the repeat-containing floral repressor gene FWA and the TE-containing floral repressor FLOWERING LOCUS C (FLC).
2012-09-12 | GSE39158 | GEO
Project description:Arbuscular mycorrhizal (AM) fungi form mutualistic relationships with most land plant species. AM fungi have long been considered as ancient asexuals. Long-term clonal evolution would be remarkable for a eukaryotic lineage and suggests the importance of alternative mechanisms to promote genetic variability facilitating adaptation. Here, we assessed the potential of transposable elements (TEs) for generating genomic diversity. The dynamic expression of TEs during Rhizophagus irregularis spore development suggests ongoing TE activity. We find Mutator-like elements located near genes belonging to highly expanded gene families. Characterising the epigenomic status of R. irregularis provides evidence of DNA methylation and small RNA production occurring at TE loci. Our results support a potential role for TEs in shaping the genome, and roles for DNA methylation and small RNA-mediated silencing in regulating TEs. A well-controlled balance between TE activity and repression may therefore contribute to genome evolution in AM fungi.
2022-02-17 | PXD025245 | Pride
Project description:Background: The small RNAs that Transposable Elements generate are vastly different when they are transcriptionally silenced compared to when they are transcriptionally activated. We performed the deep sequencing of small RNAs in a number of small RNA biogenesis mutants in both Transposable Element-silenced and Transposable Element-active epigenome backgrounds. Results: We found that Transposable Elements generate large amounts of 21-22nt siRNAs only when they are transcriptionally active. These 21-22nt siRNAs are incorporated into the AGO6 protein. Conclusion: Ago6 is the key protein that bridges the post-transcriptional degradation of Transposable Element mRNAs and the establishment of DNA methylation. Examination of flower bud small RNAs from wild type and 5 single or double mutant combinations, many of which have biological replicates. In addition, IP purification of the AGO6 protein (and mock no-antigen controls) followed by sequencing of the incorporated small RNAs. Replicate A for Col and ddm1 are submitted in GSE41755
2014-11-14 | E-GEOD-57191 | biostudies-arrayexpress
Project description:Transposable elements (TEs) are self-mobilizing elements that make up a large fraction of mammalian genomes. PIWI proteins and PIWI interacting RNAs (piRNAs) are a part of a system aimed at controlling and preventing TE proliferation. We examined the TE landscape and piRNA repertoires from three non-model Laurasiatherian mammals (dog, horse and big brown bat) with differing TE complements and proliferation patterns to address questions about the evolutionary relationships between piRNAs and TEs. We found that the genomic abundance of new TEs may not match TE transcription. We speculate that a higher rate of SINE targeting by piRNAs in the horse genome contributed to the reduced SINE insertion rate.
2017-03-26 | GSE56336 | GEO
Project description:Transposable elements (TEs) account for over half of the human genome and are often derepressed in cancer. TEs can add cryptic splice sites, undergo exonization, and generate gene–TE fusion transcripts, but the combined effects of TEs on RNA processing and translation in glioblastoma stem cells (GSCs) remains incompletely elucidated. We combined long-read RNA sequencing with polysome profiling in four patient-derived GSCs and two neural stem cell (NSC) controls to resolve TE-associated transcript diversity and its relationship to ribosomal engagement. Across GSCs, we identified 13,421 alternative splicing (AS) events, 3,077 of which contained TEs within 150 bp of splice junctions. AS sites proximal to TEs were associated with increased isoform switching compared to non–TE-associated AS sites (odds ratio 2.9 - 4.3). Moreover, AS isoforms generated from TE-proximal sites were more likely to exhibit altered ribosomal association (odds ratio 2.54). Directional shifts were observed, with shorter isoforms associating with monosome fractions and longer isoforms with polysome fractions. To enable systematic detection of gene - TE chimeric transcripts, we developed FuTER (Fusion TE Reporter), a long-read–based framework for identifying TE-associated fusions. Application to GSC datasets identified 78 GSC enriched fusion transcripts, several supported by breakpoint-spanning reads in polysome fractions, consistent with ribosome association. Our data suggest that TEs correlate with abnormal splicing activity and altered ribosome engagement in glioblastoma stem cells. By integrating long-read sequencing with polysome profiling and fusion detection, we establish a framework for analysis of TE-induced transcript diversity and its effects on cancer evolution and plasticity.
2026-06-19 | GSE326349 | GEO