Heterochromatin Protein 1 (HP1) is a major regulator of chromatin structure and function. In animals, the network of proteins interacting with HP1 is mainly associated with constitutive heterochromatin marked by H3K9me3. HP1 physically interacts with the putative orthologue of the SNF2 chromatin remodeler ATRX, which controls deposition of the histone variant H3.3 in mammals. In Arabidopsis thaliana, we show that the orthologue of ATRX participates in H3.3 deposition and characterize the function of conserved domains of plant ATRX. We show that the plant Like HP1 (LHP1) interacts with ATRX through domains that evolved specifically in land plants ancestors. Interaction between ATRX and LHP1 affects the expression of a limited subset of genes controlled by the POLYCOMB REPRESSIVE COMPLEX 2 (PRC2), including the flowering time regulator FLC. In the context of flowering time, ATRX function requires the novel LHP1-interacting domain and the ATPase of the ATRX SNF2 helicase. We conclude that distinct evolutionary pathways led to interaction between ATRX and HP1 in mammals or its counterpart LHP1 in plants, resulting in distinct modes of transcriptional regulation. Overall design: 1 sample (mutant) + 1 reference sample (control)
LHP1 Interacts with ATRX through Plant-Specific Domains at Specific Loci Targeted by PRC2.
Age, Specimen part, Subject
View SamplesWe performed total RNA-Seq and compared expression levels of genes of whole blood cells isolated from patients after kidney transplantation with stable graft function, antibody mediated- and t cell mediated graft rejection. Overall design: Whole blood cells were isolated from 6 patients with stable graft function, 6 patients with histologically verified antibody mediated graft rejection episode and 4 patients with histologically verified T cell mediated graft rejection after kidney transplantation. Total RNA was extracted and cDNA libraries for total RNA sequencing were generated using “TruSeq® Stranded Total RNA Library” kit (Illumina, San Diego, CA, USA).
The regulation of interferon type I pathway-related genes RSAD2 and ETV7 specifically indicates antibody-mediated rejection after kidney transplantation.
Specimen part, Subject
View SamplesDEAD-box RNA helicases eIF4A and Ded1 are believed to promote translation initiation by resolving mRNA secondary structures that impede ribosome attachment at the mRNA 5' end or subsequent scanning of the 5'UTR, but whether they perform distinct functions or act redundantly in vivo is poorly understood. We compared the effects of mutations in Ded1 or eIF4A on global translational efficiencies (TEs) in yeast by ribosome footprint profiling. Despite similar reductions in bulk translation, inactivation of a cold-sensitive Ded1 mutant substantially reduced the TEs of >600 mRNAs, whereas inactivation of a temperature-sensitive eIF4A mutant yielded <40 similarly impaired mRNAs. The broader requirement for Ded1 did not reflect more pervasive secondary structures at low temperature, as inactivation of temperature-sensitive and cold-sensitive ded1 mutants gave highly correlated results. Interestingly, Ded1-dependent mRNAs exhibit greater than average 5'UTR length and propensity for secondary structure, implicating Ded1 in scanning though structured 5' UTRs. Reporter assays confirmed that cap- distal stem-loop insertions increase dependence on Ded1 but not eIF4A for efficient translation. While only a small fraction of mRNAs is strongly dependent on eIF4A, this dependence is significantly correlated with requirements for Ded1 and 5'UTR features characteristic of Ded1- dependent mRNAs. Our findings suggest that Ded1 is critically required to promote scanning through secondary structures within 5'UTRs; and while eIF4A cooperates with Ded1 in this function, it also promotes a step of initiation common to virtually all yeast mRNAs. Overall design: We compared the effects of mutations in Ded1 or eIF4A on global translational efficiencies (TEs) in yeast by ribosome footprint profiling.The study includes 32 samples, comprised of 16 mRNA-Seq samples and 16 ribosome footprint profiling samples, derived from biological replicates of 3 mutant strains, ded1-cs, ded1-ts and tif1-ts, and the corresponding wild-type strains. The tif1-ts mutant and its wild-type counterpart were analyzed at 30°C and 37°C.
Functional interplay between DEAD-box RNA helicases Ded1 and Dbp1 in preinitiation complex attachment and scanning on structured mRNAs in vivo.
Subject
View SamplesSpinal muscular atrophy (SMA) is one of the most common inherited forms of neurological disease leading to infant mortality. Patients exhibit selective loss of lower motor neurons resulting in muscle weakness, paralysis, and often death. Although patient fibroblasts have been used extensively to study SMA, motor neurons have a unique anatomy and physiology which may underlie their vulnerability to the disease process. Here we report the generation of induced pluripotent stem (iPS) cells from skin fibroblast samples taken from a child with SMA. These cells expanded robustly in culture, maintained the disease genotype, and generated motor neurons that showed selective deficits compared to those derived from the childs unaffected mother. This is the first study to show human iPS cells can be used to model the specific pathology seen in a genetically inherited disease. As such, it represents a promising resource to study disease mechanisms, screen novel drug compounds, and develop new therapies.
Induced pluripotent stem cells from a spinal muscular atrophy patient.
No sample metadata fields
View SamplesAlthough many genes have been proposed to be involved in prostate carcinogenesis, no single gene or gene profile has shown to have prognostic value. The main challenge for clinical management is to distinguish slowly growing tumors from those that will relapse. In this study, we compared expression profiles of 18 prostate samples (7 with Gleason 6, 8 with Gleason 7 and 3 with Gleason score equal or higher than 8) and 5 non-neoplastic prostate samples, using the GeneChip Human Exon Array 1.0 ST of Affymetrix. Microarray analysis revealed 99 genes showing statistically significant differences among tumors with Gleason score 6, 7 and 8. In addition, mRNA expression of 29 selected genes was analyzed by qRT-PCR with microfluidic cards in an extended series of 30 prostate tumors. From these, 29 were selected to be validated and the differential expression of 18 of them (62%) was independently confirmed by quantitative real-time RT-PCR (14 upregulated and 4 downregulated in higher Gleason scores) in the extended series. This list was further narrowed down to 12 genes that were differentially expressed in tumors with Gleason score of 6-7 vs 8. Finally, the protein levels of two genes from the 12-gene signature (SEC14L1 and TCEB1) were additionally validated by immunohistochemistry. Strong protein levels of both genes were correlated with Gleason score, stage, and PSA progression.
A 12-gene expression signature is associated with aggressive histological in prostate cancer: SEC14L1 and TCEB1 genes are potential markers of progression.
Specimen part
View SamplesComparative microarray-based transcriptome analysis of A. thaliana mlo2 mlo6 mlo12 mutants and wild type plants upon Golovinomyces orontii inoculation revealed an increased and accelerated accumulation of many defense-related transcripts. Despite the biotrophic nature of the interaction, this included the non-canonical activation of a jasmonic acid/ethylene-dependent transcriptional program.
Key Components of Different Plant Defense Pathways Are Dispensable for Powdery Mildew Resistance of the Arabidopsis <i>mlo2 mlo6 mlo12</i> Triple Mutant.
Specimen part, Treatment
View SamplesEpidermal stem cells ensure proper faring of skin homeostatic processes under both physiological and challenging conditions. Currently, the molecular events underpinning ageing within the epidermal stem cell niche are poorly understood.
In Silico Analysis of the Age-Dependent Evolution of the Transcriptome of Mouse Skin Stem Cells.
Age, Specimen part
View SamplesPhytochromes are red/far red photosensors regulating numerous developmental programs in plants. Among them phytochrome A (phyA) is essential to enable seedling de-etiolation in continuous far-red (FR) light a condition mimicking the environment under a dense canopy. The ecological relevance of this response is demonstrated by the high mortality rate of phyA mutants germinating in deep vegetational shade. phyA signaling involves a direct interaction of the photoreceptor with members of the bHLH transcription factor family, PIF1 and PIF3 (Phytochrome Interacting Factor). Here we investigated the involvement of PIF4 and PIF5 in phyA signaling and found that they redundantly control de-etiolation in FR light. The pif4pif5 double mutant is hypersensitive to low fluence rates of FR light. This phenotype is dependent on FR light perception by phyA but does not rely on alterations of the phyA level. Our microarrays analysis shows that PIF4 and PIF5 are part of an inhibitory mechanism repressing the expression of some light-responsive genes in the dark and are also needed for full expression of several growth-related genes in the light. Unlike PIF1 and PIF3, PIF4 and PIF5 are not degraded in response to FR light indicating that they are light-regulated by a different mechanism. Our genetic analysis suggests that this is achieved through the sequestration of these PIFs by the closely related bHLH transcription factor HFR1 (long Hypocotyl in FR light).
Phytochrome interacting factors 4 and 5 redundantly limit seedling de-etiolation in continuous far-red light.
No sample metadata fields
View SamplesWe analysed whole PolyA+ RNA from human osteosarcoma U2OS cells depleted for human Cactin or transfected with a control shRNA. Overall design: Two independent shRNAs targeting human Cactin (shCac_C and shCac_D), a control shRNA (shCtrl), a single cell line (U2OS)
Human cactin interacts with DHX8 and SRRM2 to assure efficient pre-mRNA splicing and sister chromatid cohesion.
Cell line, Treatment, Subject, Time
View SamplesDepression is a complex and heterogeneous disorder and a leading contributor to the global burden of of disease. Most previous research has focused on individual brain regions and individual genes that contribute to depression. However, emerging evidence in both humans and animal models suggests that dysregulated circuit function and gene expression across multiple brain regions drive depressive phenotypes. Here we use a bioinformatics approach intersecting differential expression analysis with weighted gene co-expression network analysis to identify transcriptional networks that regulate susceptibility to depressive-like symptoms in mice. We performed RNA-sequencing on multiple brain regions from control animals and those either susceptible or resilient to chronic social defeat stress (CSDS) at multiple time points after defeat. We bioinformatically identified several transcriptional networks that regulate depression susceptibility, and in vivo manipulations of these networks confirmed their functional significance at the levels of gene transcription, synaptic regulation, and behavior. Our findings reveal novel transcriptional networks that control stress susceptibility and offer fundamentally new leads for antidepressant drug discovery. Overall design: RNA-seq samples were generated from 4 brain regions (nucleus accumbens (NAC), prefrontal cortex (PFC), amygdala (AMY) and ventral hippocampus (VHIP) ) at 3 time-points (48h, 28d, 28d +1h stress) after chronic social defeat stress in control, susceptible and resilient mice. Additionally, RNA-seq samples were generated from virally infected VHIP tissue (HSV-GFP or HSV-Dkkl1) after an accelerated social defeat to assess the effect of Dkkl1 over-expression.
Circuit-wide Transcriptional Profiling Reveals Brain Region-Specific Gene Networks Regulating Depression Susceptibility.
Specimen part, Cell line, Subject, Time
View Samples