We have analysed a family with an autosomal recessive type of tetraplegic cerebral palsy with mental retardation, reduction of cerebral white matter, and atrophy of the cerebellum in an inbred sibship.
Mutation in the AP4M1 gene provides a model for neuroaxonal injury in cerebral palsy.
Sex, Specimen partView Samples
The spatial organization of DNA in the cell nucleus is an emerging key contributor to genomic function. We have developed 4C technology, or 3C-on-chip, which allows for an unbiased genome-wide search for DNA loci that contact a given locus in the nuclear space. We demonstrate here that active and inactive genes are engaged in many long-range intrachromosomal interactions and can also form interchromosomal contacts. The active b-globin locus in fetal liver contacts mostly transcribed, but not necessarily tissue-specific, loci elsewhere on chromosome 7, while the inactive locus in fetal brain contacts different, transcriptionally silent, loci. A housekeeping gene in a gene dense region on chromosome 8 forms long-range contacts predominantly with other active gene clusters, both in cis and in trans, and many of these intra- and interchromosomal interactions are conserved between the tissues analyzed. Our data demonstrate that chromosomes fold into areas of active chromatin and areas of inactive chromatin and establish 4C technology as a powerful tool to study nuclear architecture.
Nuclear organization of active and inactive chromatin domains uncovered by chromosome conformation capture-on-chip (4C).
Specimen partView Samples
We describe a novel quantitative cDNA expression profiling strategy, involving amplification of the majority of mouse transcriptome using a defined set of 44 heptamer primers. The amplification protocol allows for efficient amplification from as low as 50pg of mRNA and did not alter the expression of the transcripts even with 200 fold dilution of the minimum requirement of the starting material (10ng of mRNA) for standard RNA-seq protocols. We implemented our methodology on embryological lineage segregation, achieved by graded activation of Activin A/TGFß signaling in mouse embryonic stem cells (mESCs). The fold changes in transcript expression were in excellent agreement with quantitative RT-PCR and we observed a dynamic range spanning more than five orders of magnitude in RNA concentration with a reliable estimation of low abundant transcripts. Our transcriptome data identified key lineage markers, while the high sensitivity showed that novel lineage specific transcripts anticipate the differentiation of specific cell types. We compared our strategy with Std. RNA-seq (Mortazavi et al. 2008) and SMART-seq (Ramsköld et al. 2012). We also showed potential of our methodology to suppress the representation of highly expressing ribosomal transcripts. Overall design: Sequencing was performed on day 4 differentiating mouse ESCs treated for two days with 3 different dosages of Activin A (3ng/mL, 15ng/mL and 100ng/mL). The cells were also treated with SB-431542. Serial dilutions of mRNA derived Activin A(3ng/mL) samples were used to detemine the minimum amount of mRNA required to construct relaible sequencing library. SMARTseq libraries were prepared for both Activin A(3ng/mL) and Activin A(100ng/mL) samples. Three Different primer sets were designed to suppress the representaiton of Ribosomal transcripts.
Quantitative transcriptomics using designed primer-based amplification.
Specimen part, TreatmentView Samples
Nuclear receptors (NRs) are ligand-activated transcription factors regulating a large variety of processes involved in reproduction, development, and metabolism. NRs are ideal drug targets. Immortalized cell lines recapitulate NR biology very poorly and primary cultures are laborious and require a constant need for donor material. There is a clear need for development of novel preclinical model systems that better resemble human physiology since technical uncertainty early in drug development is the cause of many preclinical drugs not reaching the clinic. Here, we studied whether organoids, mini-organs derived from the respective tissues stem cells, can serve as a novel (preclinical) model system to study NR biology and targeteability. We characterized mRNA expression profiles of the NR superfamily in mouse liver, ileum, and colon organoids. NR mRNA expression patterns were similar to the respective tissues, indicating their suitability for NR research. Metabolic NRs Fxr, Lxr, Lxr, Ppar, and Ppar were responsive to ligands in an NR-dependent fashion, as demonstrated by regulation of expression and binding to endogenous target genes. Transcriptome analyses of wildtype colonic organoids stimulated with Rosiglitazone showed that lipid metabolism was the highest significant changed function, greatly mimicking the known function of PPARs and Rosiglitazone in vivo. In conclusion, our results demonstrate that organoids constitutes a versatile and promising in vitro system to study NR biology and targeteability.
Characterization of stem cell-derived liver and intestinal organoids as a model system to study nuclear receptor biology.
Findings suggest that PPARalpha plays a decisive role in the development of hypertrophy, affecting the functional outcome of the heart. Unfortunately, information on the nature of PPARalpha-dependent processes in cardiac hypertrophy is fragmentary and incomplete.
Transcriptomic analysis of PPARalpha-dependent alterations during cardiac hypertrophy.
No sample metadata fieldsView Samples
To study the senescence gene signatures in the cells, which were genetic SMARCB1 depleted or treated with aurora kinase inhibitors or etoposide, we performed next generation RNA sequencing on these cell, and ''FRIDMAN_SENESCENCE_UP'' geneset was used to determine the enrichment of senescence-related genes. The RNA sequencing results include (1) A375 cells and SMARCB1 depleted counterparts. (2) A549 cells and aurora kinase inhibitor (Alisertib, barasertib or tozasertib) or etoposide treated counterparts. Overall design: RNA seq data of A375_gSMARCB1 + A549_etoposide, Aurora kinases inhibitors treated, to check senescence gene expression signature one replicate of A375 cells parental V.S SMARCB1 KO (by CRISPR) + duplicates of A549 parental V.S etoposide, or 3 indepdent aurora kinase inhibitors (MLN8237/Alisertib, VX680/Tozasertib, AZD1132/Barasertib)
High-Throughput Functional Genetic and Compound Screens Identify Targets for Senescence Induction in Cancer.
Disease, Disease stage, Cell line, SubjectView Samples
Transcriptome analyses on seeds developed in different parental conditions
Effects of Parental Temperature and Nitrate on Seed Performance are Reflected by Partly Overlapping Genetic and Metabolic Pathways.
No sample metadata fieldsView Samples
We analysed the transcriptome of dry seeds (the end product of seed maturation) of three genotypes with different DOG1 expression levels. These included the WT Ler (low DOG1 expression), the near isogenic line NILDOG1-Cvi (strong DOG1 expression) and the non-dormant dog1-1 mutant (absence of DOG1 expression). NILDOG1-Cvi is the Ler WT containing an introgression of the Cvi accession on chromosome 5, which includes the DOG1 gene (Bentsink et al., 2006). The dog1-1 mutant is in the NILDOG1-Cvi genetic background.
The Arabidopsis DELAY OF GERMINATION 1 gene affects ABSCISIC ACID INSENSITIVE 5 (ABI5) expression and genetically interacts with ABI3 during Arabidopsis seed development.
Specimen partView Samples
Previously, long-term effects on body weight and reproductive performance have been demonstrated in the chicken model of prenatal protein undernutrition by albumen removal. Introduction of such persistent alterations in phenotype suggests stable changes in gene expression. A genome-wide screening for differences in hepatic transcriptome by RNA-Seq was performed in adult Isa Brown hens (55 weeks of age). Albumen-deprived hens were created by removal of 3 ml of the albumen from fertilized eggs and replacement with saline early during embryonic development (embryonic day 1). Results were compared to mock-treated sham hens and non-treated control hens. Correlation between relative expression levels obtained from the RNA-Seq and qPCR results was very high (Pearson’s correlation coefficiënt = 0.85), confirming the validity of the RNA-Seq results. In addition, after expansion of the sample size, 7 out of 15 selected genes demonstrated the same significant gene expression differences in the qPCR as in the RNA-Seq dataset, and were thus biologically confirmed. Grouping of the differentially expressed (DE) genes according to biological functions revealed the involvement of processes such as ‘embryonic and organismal development’, ‘organ morphology’, ‘organ and tissue development’, ‘reproductive system development and function’. Molecular pathways that were altered were ‘amino acid metabolism’, ‘molecular transport’, ‘small molecule biochemistry’, ‘cell death and survival’, ‘cell-to-cell signaling and interaction’, ‘carbohydrate metabolism’ and ‘protein synthesis’. In conclusion, the present results demonstrated for the first time that prenatal protein undernutrition by albumen removal leads to long-term alterations of the hepatic transcriptome in the chicken. Overall design: 3 biological replicates per group (control, sham, albumen-deprived) were analyzed
Differential Expression of Genes and DNA Methylation associated with Prenatal Protein Undernutrition by Albumen Removal in an avian model.
Cell line, SubjectView Samples
Defective complex I (CI) is the most common type of oxidative phosphorylation (OXPHOS) disease in patients, with an incidence of 1 in 5,000 live births. Complex I deficiency can present in infancy or early adulthood and shows a wide variety of clinical manifestations, including Leigh syndrome, (cardio)myopathy, hypotonia, stroke, ataxia and lactic acidosis. A number of critical processes and factors, like superoxide production, calcium homeostasis, mitochondrial membrane potential and mitochondrial morphology, are known to be involved in clinical CI deficiency, but not all factors are yet known and a complete picture is lacking.
Transcriptional changes in OXPHOS complex I deficiency are related to anti-oxidant pathways and could explain the disturbed calcium homeostasis.
Sex, Age, Specimen part, Disease, Disease stageView Samples