Background: Eukaryotic cells express a complex layer of noncoding RNAs. An intriguing family of regulatory RNAs includes transcripts from the opposite strand of protein coding genes, so called natural antisense transcripts (NATs). Here, we test the hypothesis that antisense transcription triggers RNA interference and gives rise to endogenous short RNAs (endo-siRNAs). Methods/Results: We used cloned human embryonic kidney cells (HEK293) followed by short RNAseq to investigate the small genic RNA transcriptome. 378 genes gave rise to short RNA reads that mapped to exons of RefSeq genes. The length profile of short RNAs showed a broad peak of 20-24 nucleotides, indicative of endo-siRNAs. Collapsed reads mapped predominantly to the first and the last exon of genes (74%). RNAs reads were intersected with sequences occupied by RNAPolII or bound to Argonaute (AGO1 by crosslinking, ligation, and sequencing of hybrids, CLASH). In the first exon, 94% of the reads correlated with PolII occupancy with an average density of 130 (relative units); this decreased to 65%/20 in middle exons and 54%/12 in the last exon. CLASH reads mapping to multi-exon genes showed little distribution bias with an average of about 5 CLASH reads overlapping with 60% of the endo-siRNA reads. However, endo-siRNAs (21-25 nt) intersecting with CLASH reads were enriched at the 5''end and decreased towards the 3''end. We then investigated the 378 genes with particular focus on features indicative for short RNA production; however, found that endo-siRNA numbers did not correlate with gene structures that favor convergent transcription. In contrast, our gene set was found notably over-represented in the NATsDB sense/antisense group as compared to non-overlapping and non-bidirectional groups. Moreover, read counts showed no correlation with the steady-state levels of the related mRNAs and the pattern of endo-siRNAs proved reproducible after an induced mutagenic insult. Conclusions: Our results suggest that antisense transcripts contribute to low levels of endo-siRNAs in fully differentiated human cells. A characteristic endo-siRNA footprint is being produced at sites of RNAPolII transcription which is also related to AGO1. This endo-siRNA signature represents an intriguing finding and its reproducibility suggests that the production of endo-siRNAs is a regulated process with potential homoeostatic impact. Overall design: Size selected RNASeq of 3 human embryonic kidney cell (HEK293) samples. 1 control and 2 samples exposed to 100 µg/ml ethyl methanesulfonate for 24 hrs.
Contribution of natural antisense transcription to an endogenous siRNA signature in human cells.
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View SamplesP1 encodes an R2R3-MYB transcription factor responsible for the accumulation of insecticidal flavones in maize silks and red phlobaphene pigments in pericarps and other floral tissues, which contributed to making P1 an important visual marker since the dawn of modern genetics. We conducted RNA-Seq using pericarps at two different stages, 14 and 25 days after pollination (DAP). High-throughput sequencing using the Illumina platform resulted in the generation of ~20 million high quality reads, from which ~90% aligned to the recently completed maize genome sequence corresponding to ~5 million reads for each one of the four samples. Overall design: Examination of two different RNA samples from two different stages of maize pericarp tissues.
A genome-wide regulatory framework identifies maize pericarp color1 controlled genes.
Specimen part, Subject
View SamplesP1 encodes an R2R3-MYB transcription factor responsible for the accumulation of insecticidal flavones in maize silks and red phlobaphene pigments in pericarps and other floral tissues, which contributed to making P1 an important visual marker since the dawn of modern genetics. We conducted RNA-Seq using from maize silks obtained at 2-3 days after emergence. High-throughput sequencing using the Illumina platform resulted in the generation of ~14 million high quality reads, corresponding to ~7 million reads for each sample, from which 76% aligned to the maize genome. Overall design: Examination of two different RNA samples from maize silks obtained at 2-3 days after emergence
A genome-wide regulatory framework identifies maize pericarp color1 controlled genes.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Brain transcriptional and epigenetic associations with autism.
Age, Specimen part, Disease, Disease stage, Subject
View SamplesAutism is a common neurodevelopmental syndrome. Numerous rare genetic etiologies are reported; most cases are idiopathic. To uncover important gene dysregulation in autism we analyzed carefully selected idiopathic autistic and control cerebellar and BA19 (occipital) brain tissues using high resolution whole genome gene expression and DNA methylation microarrays. No changes in DNA methylation were identified in autistic brain but gene expression abnormalities in two areas of metabolism were apparent: down-regulation of genes of mitochondrial oxidative phosphorylation and of protein translation. We also found associations between specific behavioral domains of autism and specific brain gene expression modules related to myelin/myelination, inflammation/immune response and purinergic signaling. This work highlights two largely unrecognized molecular pathophysiological themes in autism and suggests differing molecular bases for autism behavioral endophenotypes.
Brain transcriptional and epigenetic associations with autism.
Age
View SamplesThe oxt6 mutant is an oxidative stress-tolerant Arabidopsis mutant that is deficient in a polyadenylation factor subunit. Expression analysis suggests that impaired poly(A) site choice is responsible for the stress-tolerant phenotype.
A polyadenylation factor subunit implicated in regulating oxidative signaling in Arabidopsis thaliana.
No sample metadata fields
View SamplesTranscription profiling of Arabidopsis mutant ron1-1 vs the wild type Ler
The RON1/FRY1/SAL1 gene is required for leaf morphogenesis and venation patterning in Arabidopsis.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Genetic correction of human induced pluripotent stem cells from patients with spinal muscular atrophy.
Specimen part
View SamplesSpinal Muscular Atrophy (SMA) is an autosomal recessive motor neuron disease and is the second most common genetic disorder leading to death in childhood. Motoneurons derived from induced pluripotent stem cells (iPS cells) obtained by reprogramming SMA patient and his healthy father fibroblasts, and genetically corrected SMA-iPSC obtained converting SMN2 into SMN1 with target gene correction (TGC), were used to study gene expression and splicing events linked to pathogenetic mechanisms.
Genetic correction of human induced pluripotent stem cells from patients with spinal muscular atrophy.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Combined inhibition of DDR1 and Notch signaling is a therapeutic strategy for KRAS-driven lung adenocarcinoma.
Specimen part
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