Mu killer-mediated and spontaneous silencing of Zea mays Mutator family transposable elements define distinctive paths of epigenetic inactivation
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ABSTRACT: Mu killer contains a partial inverted duplication of the mudrA transposase gene and two copies of the terminal inverted repeat A region of MuDR. Mu killer can effectively silence single copy MuDR/Mu lines but failed to silence about 25% of the time in multiple copy lines. Mu killer was partially sequenced and shown to be collinear with mudrA. Mu killer individuals that silenced MuDR contained two short antisense transcripts, while individuals that failed to silence MuDR contained multiple sense transcripts but no antisense transcripts. Transcriptomes from Mu killer-silenced individuals were compared to epigenetically silenced lines; the 2 silencing mechanisms were shown to affect different pathways. 4 replicates of the Mu-active and Mu-inactive lines at 2 anther stages (1.0mm, 2.00mm) with a balanced dye-swap design. Normalized intensities for each channel are provided.
Project description:Mu killer contains a partial inverted duplication of the mudrA transposase gene and two copies of the terminal inverted repeat A region of MuDR. Mu killer can effectively silence single copy MuDR/Mu lines but failed to silence about 25% of the time in multiple copy lines. Mu killer was partially sequenced and shown to be collinear with mudrA. Mu killer individuals that silenced MuDR contained two short antisense transcripts, while individuals that failed to silence MuDR contained multiple sense transcripts but no antisense transcripts. Transcriptomes from Mu killer-silenced individuals were compared to epigenetically silenced lines; the 2 silencing mechanisms were shown to affect different pathways.
Project description:MuDR/Mu are a highly active transposon family moving by either cut only (or cut-and-paste) in strictly somatic tissues or net replicative transposition (absence of excision alleles) in reproductive tissues. Aside from the MuDR-encoded MURA and MURB proteins, other factors required for Mu transposition, particularly those contributing to the developmentally specific behavior, have yet to be identified. To address this question and assess the impact of a highly active transposon on the transcriptome, RNA was extracted from anthers at three developmental stages in Mu-active and -inactive stocks and compared on a 44,000 element oligonucleotide array. We found that approximately 30,000 unique genes are expressed at each stage. Of the ~10% (ca. 3000) differentially regulated transcripts per stage, there was approximately equal representation by the active or inactive individuals. Keywords: anther development, maize, Mu, transposon
Project description:To extend our previous knowledge from our gene expression studies on Flower pedicel Abscission zone using Affymetrix microarray chip we have employed whole transcriptome analysis by NGS as a discovery platform to identify and add the transcripts to pre-existing database. We designed the Customized AZ Microarray chip with the transcripts obtained from NGS (includes novel transcripts), pre existing Agilent probes, and some additional transcripts from previous databases. we developed transgenic lines by antisense silenciencing the genes, which are expressed in the AZ to study the functional role in abscission process. In the current stuty we silenced TPRP gene by antisense technology under abscisson promoter (TAPG::antsisense TPRP). The flower pedicel AZ tissue tissue was sampled at six time points (0, 4, 8, 12, 16 and 20 h), following flower removal, and analyzed for their gene expression profiles using the customized AZ microarray.
Project description:To extend our previous knowledge from our gene expression studies on Flower pedicel Abscission zone using Affymetrix microarray chip we have employed whole transcriptome analysis by NGS as a discovery platform to identify and add the transcripts to pre-existing database. We designed the Customized AZ Microarray chip with the transcripts obtained from NGS (includes novel transcripts), pre existing Agilent probes, and some additional transcripts from previous databases. We developed transgenic lines by antisense silencing the genes, which are expressed in the AZ to study the functional role in abscission process. In the current stuty we silenced KD gene by antisense technology under abscisson promoter (TAPG::antsisense KD). The flower pedicel AZ tissue tissue was sampled at six time points (0, 4, 8, 12, 16 and 20 h), following flower removal, and analyzed for their gene expression profiles using the customized AZ microarray.
Project description:Unrestricted movement of mobile genetic elements could cause pre-mature lethality in Drosophila melanogaster. Specifically, retro transposons can disrupt genomic integrity through insertions, deletions and chromosomal rearrangements. Therefore, eukaryotes have developed defense mechanisms to silence these elements. In Drosophila, endogenous small interfering (endo-siRNAs) repress retro transposon mobility in somatic cells. The generation of endo-siRNAs requires Dicer-2 processing of double-stranded RNA precursors, yet the origins of this precursor are unknown. Here we show that retro transposons in Dmel-2 cells produce sense and antisense transcripts and identify bonafide transcription start sites for these RNAs. We determine that retro transposon antisense transcripts are less polyadenylated than sense transcripts. RNA-seq and small RNA-seq upon Dicer-2 depletion showed global decrease in endo-siRNAs mapping to retro transposons and increased expression of both S and AS retro transposon transcripts. These data support a model in which double-stranded RNA precursors are derived from convergent transcription and retained in the nucleus. Dicer-2 processes these precursors into endo-siRNAs that silence both sense and antisense retro transposon transcripts. Reduction of sense retro transposon transcripts potentially lowers element specific protein levels required for movement. This mechanism preserves genomic integrity and is especially important for Drosophila fitness because mobile genetic elements are highly active.
Project description:<p>High throughput RNA Sequencing has revealed that the human genome is widely transcribed. However, the extent of natural antisense transcription, the molecular mechanisms by which natural antisense transcripts (NATs) might affect their cognate sense genes, and the role of NATs in cancer are less well understood. Here, we use strand-specific paired-end RNA sequencing (ssRNASeq) on a cohort of 376 cancer patients covering 9 tissue types to comprehensively characterize the landscape of antisense expression. Our results reveal that greater than 60% of annotated transcripts have measureable antisense expression and the expression of sense and antisense transcript pairs is in general positively correlated. Furthermore, by studying the expression of sense/antisense pairs across tissues we identify lineage-specific, ubiquitous and cancer-specific antisense loci. Our results raise the possibility that NATs participate in the regulation of well-known tumor suppressors and oncogenes. Finally, this study provides a catalogue of cancer related genes with significant antisense transcription (oncoNAT). This resource will allow researchers to investigate the molecular mechanisms of sense/antisense regulation and further advance our understanding of their role in cancer.</p>
Project description:Mouse liver proteome was investigated upon in vivo mouse treatment with a N-acetylgalactosamine-conjugated antisense oligonucleotide engineered to silence ceramide synthase 2 specifically in hepatocytes in vivo. The data is a part of a study on the involvement of ceramide enzymatic machinery in cardiovasular disorders and its potential as a target for the disease treatment.
2023-05-10 | PXD025957 | Pride
Project description:Novel endogenous antisense transcripts in mouse
Project description:Virus Induced Gene Silencing (VIGS) was used to silence the expression of soybean Replication Protein 3 (GmRPA3). RNAseq was used to compare gene expression in GmRPA3 silenced and empty vector treated plants