Genomic imprinting is an epigenetic phenomenon causing parental alleles to be active depending on their parent-of-origin. In plants, imprinted genes are mainly confined to the endosperm, an ephemeral tissue supporting embryo development. Differential methylation of histone H3 on lysine 27 (H3K27me3) established by the Polycomb Repressive Complex 2 (PRC2) is a major regulatory mechanism determining activity of paternally expressed imprinted genes (PEGs) in animals and plants. Here, we show that the coding region of many PEGs is marked by an epigenetic signature of H3K27me3, H3K9me2 and CHG methylation and that the combination of these three modifications correlates with paternally-biased gene expression in the endosperm. The maternal alleles of PEGs are marked by CHG methylation in the central cell, indicating that the repressive epigenetic signature of PEGs is established before fertilization. We use the presence of the three modifications to predict novel PEGs and propose that genomic imprinting is substantially more common than previously estimated based on expression data. Overall design: Col × Ler reciprocal crosses were performed using Arabidopsis lines expressing PHE1::NTF and PHE1::BirA. 4DAP siliques were collected and tissue homogenization and nuclei purification were performed from three biological replicates for LerxCol and two for ColxLer using INTACT. Total RNA was extracted from purified nuclei using the mirVana Isolation Kit Protocol (Ambion). mRNA extraction was performed using NEBNext Poly(A) mRNA Magnetic Isolation and the Libraries were prepared with the NEBNext Ultra II RNA Library Prep Kit from Illumina. Samples were sequenced at the National Genomic Infrastructure (NGI) from SciLife Laboratory (Uppsala, Sweden) on an Illumina HiSeq2500 in paired-end 125bp read length.
Epigenetic signatures associated with imprinted paternally expressed genes in the Arabidopsis endosperm.
Specimen part, Subject
View SamplesPlants with decreased SWC4 expression levels displayed several pleiotropic phenotypic alterations, suggesting that this gene participates in the regulation of different developmental processes. To evaluate genes whose expression was misregulated in SCW4 RNAi line, we performed RNA-seq differential expression analysis.
Arabidopsis SWC4 Binds DNA and Recruits the SWR1 Complex to Modulate Histone H2A.Z Deposition at Key Regulatory Genes.
Age, Specimen part
View SamplesBasilar papillae (i.e.auditory epithelia) were isolated from 4-day-old chickens and sectioned into low, middle, and high frequency segments. RNA was isolated from each segment separately, amplified using a two-cycle approach, biotinylated, and hybridized to Affymetrix chicken whole-genome arrays.
Gene expression gradients along the tonotopic axis of the chicken auditory epithelium.
Specimen part
View Samplesthe nuclear pore complex (NPC) is emerging as an important mediator of cellular processes beyond molecule transport, including control of gene expression, replication and DNA repair.
The Nup84 complex coordinates the DNA damage response to warrant genome integrity.
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A genome-wide function of THSC/TREX-2 at active genes prevents transcription-replication collisions.
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View SamplesTranscription is a major obstacle for replication fork progression and a cause of genome instability. Such instability increases in mutants with a suboptimal assembly of the nascent messenger ribonucleo-protein particle (mRNP), as THO/TREX and the NPC-associated THSC/TREX-2 complex.
A genome-wide function of THSC/TREX-2 at active genes prevents transcription-replication collisions.
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View SamplesThis SuperSeries is composed of the SubSeries listed below.
Excess of Yra1 RNA-Binding Factor Causes Transcription-Dependent Genome Instability, Replication Impairment and Telomere Shortening.
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View SamplesTranscription is a major obstacle for replication fork progression and a cause of genome instability. Such instability increases in mutants with an imbalance proportion of Yra1, a component of THO/TREX.
Excess of Yra1 RNA-Binding Factor Causes Transcription-Dependent Genome Instability, Replication Impairment and Telomere Shortening.
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View SamplesThis SuperSeries is composed of the SubSeries listed below.
The Npl3 hnRNP prevents R-loop-mediated transcription-replication conflicts and genome instability.
No sample metadata fields
View SamplesTranscription is a major obstacle for replication fork progression and a cause of genome instability. Such instability increases in mutants with a suboptimal assembly of the nascent messenger ribonucleo-protein particle (mRNP), as THO/TREX and some heterogeneous nuclear ribonucleoproteins (hnRNPs) mutants.
The Npl3 hnRNP prevents R-loop-mediated transcription-replication conflicts and genome instability.
No sample metadata fields
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