Transcriptomes of differentiated cells of the conditionally immortalized mouse podocyte cell line SVI (Schiwek et al., Kidney Int. 66: 91-101, 2004) were determined as described in Warsow et al. (Kidney Int. 84: 104-115, 2013) after application of mechanical stress (Endlich et al., J. Am. Soc. Nephrol. 12: 413-422, 2001) as compared to control conditions.
Mechanical stress enhances CD9 expression in cultured podocytes.
Specimen part, Cell line
View SamplesTruncating mutations of CHD8, encoding a chromodomain helicase, and of many other genes with diverse functions, are strong-effect risk factors for autism spectrum disorder (ASD), suggesting multiple mechanisms of pathogenesis. We explored the transcriptional networks that CHD8 regulates in neural progenitor cells (NPCs) by reducing its expression and then integrating transcriptome sequencing (RNA-seq) with genome-wide CHD8 binding (ChIP-seq). Suppressing CHD8 to levels comparable with loss of a single allele caused altered expression of 1,756 genes, 64.9% of which were up-regulated. CHD8 showed widespread binding to chromatin, with 7,324 replicated sites that marked 5,658 genes. Integration of these data suggests that a limited array of direct regulatory effects of CHD8 produced a much larger network of secondary expression changes. Genes indirectly down-regulated (i.e., without CHD8 binding sites) reflect pathways involved in brain development, including synapse formation, neuron differentiation, cell adhesion, and axon guidance, whereas CHD8-bound genes are strongly associated with chromatin modification and transcriptional regulation. Genes associated with ASD were strongly enriched among indirectly down-regulated loci (p = 1.01x10-9) and CHD8-bound genes (p = 4.34x10-3), which align with previously identified co-expression modules during fetal development. We also find an intriguing enrichment of cancer related gene-sets among CHD8-bound genes (p < 1.9x10-11). In vivo suppression of chd8 in zebrafish produced macrocephaly comparable to that of humans with inactivating mutations. These data indicate that heterozygous disruption of CHD8 precipitates a network of gene expression changes involved in neurodevelopmental pathways in which many ASD-associated genes may converge on shared mechanisms of pathogenesis. Overall design: RNA-seq in NPCs treated with shRNAs targeting CHD8. For controls, NPCs were treated with shRNAs targeting GFP and LacZ. Infection and sequencing was carried out in two separate batches, with one GFP and one LacZ sample in each batch. All samples were sequenced in two technical replicates.
CHD8 regulates neurodevelopmental pathways associated with autism spectrum disorder in neural progenitors.
No sample metadata fields
View SamplesThe 600kb BP4-BP5 16p11.2 CNV (copy number variant) is associated with neuroanatomical, neurocognitive and metabolic disorders. These recurrent rearrangements are associated with reciprocal phenotypes such as obesity and underweight, macro- and microcephaly, as well as autism spectrum disorder (ASD) and schizophrenia. Here we interrogated the transcriptome of individuals carrying reciprocal CNVs in 16p11.2.
A Potential Contributory Role for Ciliary Dysfunction in the 16p11.2 600 kb BP4-BP5 Pathology.
Sex, Age, Specimen part
View SamplesWe sequenced strand-specific mRNA from the heads of 3 groups of wild type zebrafish (Danio rerio) 5 days post fertilization. Overall design: Examination of the relative expression of genes in the developing zebrafish brain
BRF1 mutations alter RNA polymerase III-dependent transcription and cause neurodevelopmental anomalies.
No sample metadata fields
View SamplesHuman epidermal keratinocytes were treated with 25 ng.ml EphB2 or EFNA4, both as-Fc conjugates (Sigma).
Eph-2B, acting as an extracellular ligand, induces differentiation markers in epidermal keratinocytes.
Time
View SamplesBoth ephrins and their receptors are membrane bound, restricting their interactions to the sites of direct cell-to-cell interfaces. They are widely expressed, often co-expressed and regulate developmental processes, cell adhesion, motility, survival, proliferation, and differentiation. Both tumor suppressor and oncogene activities are ascribed to EFNs and Ephs in various contexts. A major conundrum regarding the EFN/Eph system concerns their large number and functional redundancy, given the promiscuous cross-activation of ligands and receptors and the overlapping intracellular signaling pathways. To address this issue, we treated human epidermal keratinocytes with 5 EFNAs individually and defined the transcriptional responses in the cells. We found that a large set of genes is coregulated by all EFNAs. However, while the responses to EFNA3, EFNA 4 and EFNA 5 are identical, the responses to EFNA1 and EFNA2 are characteristic and distinctive. All EFNAs induce epidermal differentiation markers and suppress cell adhesion genes, especially integrins. Ontological analysis shows that all EFNAs induce cornification and keratin genes, while suppressing wound-healing associated, signaling, receptor and ECM associated genes. Transcriptional targets of AP1 are selectively suppressed by EFNAs. EFNA1 and EFNA2, but not the EFNA3, EFNA4, EFNA5 cluster, regulate the members of the ubiquitin-associated proteolysis genes. EFNA1 specifically induces collagen production. Our results demonstrate that the EFN-Eph interactions in the epidermis, while promiscuous, are not redundant but specific. This suggests that different members of the EFN/Eph system have specific, clearly demarcated functions.
Specific and shared targets of ephrin A signaling in epidermal keratinocytes.
No sample metadata fields
View SamplesEpidermis, a continuously self-renewing and differentiating organ, produces a protective stratum corneum that shields us from external chemical, physical and microbial threats. Epidermal differentiation is a multi-step process regulated by influences, some unknown, others insufficiently explored. Detachment of keratinocytes from the basement membrane is one such pro-differentiation stimulus. Here, we define the transcriptional changes during differentiation, especially those caused by detachment from the substratum. Using comprehensive transcriptional profiling, we revisited the effects of detachment as a differentiation signal to keratinocytes. We identified the genes regulated by detachment, the corresponding ontological categories and, using metaanalysis, compared the genes and categories to those regulated by other pro-differentiating stimuli. We identified 762 genes overexpressed in suspended keratinocyte, including known and novel differentiation markers, and 1427 in attached cells, including basal layer markers. Detachment induced epidermis development, cornification and desmosomal genes, but also innate immunity, proliferation inhibitors, transcription regulators and MAPKs; conversely the attached cells overexpressed cell cycle, anchoring, motility, splicing and mitochondrial genes, and both positive and negative regulators of apoptosis. Metaanalysis identified which detachment-regulated categories overlap with those induced by suprabasal location in vivo, by reaching confluency in vitro, and by inhibition of JUN kinases. Attached and in vivo basal cells shared overexpression of mitochondrial components. Interestingly, melanosome trafficking components were also overexpressed in the attached and in vivo basal keratinocytes. Reaching confluency did not affect adhesion and ECM proteins. Lipid metabolism and steroid metabolism were induced by confluency and by JNK inhibition, respectively. These results suggest that specific pro-differentiation signals induce specific features of the keratinization process, which are in vivo orchestrated into harmonious epidermal homeostasis.
Keratinocyte detachment-differentiation connection revisited, or anoikis-pityriasi nexus redux.
Specimen part
View SamplesCultured keratinocytes treated with TNFa in the presence or absence of NFkB inhibitor; time course 1, 4, 24 & 48 hrs.
Pathway-specific profiling identifies the NF-kappa B-dependent tumor necrosis factor alpha-regulated genes in epidermal keratinocytes.
No sample metadata fields
View SamplesCultured epidermal keratinocytes treated with OsM 1, 4, 24 & 48hrs, and Skinethic epidermal substitutes treated 1, 4, 24, 48h & 7days, each with untreated control
Transcriptional responses of human epidermal keratinocytes to Oncostatin-M.
No sample metadata fields
View SamplesEpidermal keratinocytes respond to extracellular influences by activating cytoplasmic signal transduction pathways that change the transcriptional profiles of affected cells. To define responses to two such pathways, p38 and ERK, we used SB203580 and PD98059 as specific inhibitors, and identified the regulated genes after 1, 4, 24 and 48 hrs, using Affymetrix Hu133Av2 microarrays. Additionally, we compared genes specifically regulated by p38 and ERKs with those regulated by JNK and by all three pathways simultaneously. We find that the p38 pathway induces the expression of extracellular matrix and proliferation-associated genes, while suppressing microtubule-associated genes; the ERK pathway induces the expression of nuclear envelope and mRNA splicing proteins, while suppressing steroid synthesis and mitochondrial energy production enzymes. Both pathways promote epidermal differentiation and induce feedback inactivation of MAPK signaling. c-FOS, SRY and N-Myc appear to be the principal targets of the p38 pathway, Elk-1 SAP1 and HLH2 of ERK, while FREAC-4, ARNT and USF are common to both. The results for the first time comprehensively define the genes regulated by the p38 and ERK pathways in epidermal keratinocytes and suggest a list of targets potentially useful in therapeutic interventions.
Transcriptional profiling defines the roles of ERK and p38 kinases in epidermal keratinocytes.
Specimen part, Treatment
View Samples