Arp2/3 complex assembles branched actin filaments key to many cellular processes, but its organismal roles remain poorly understood. Here we employed conditional arpc4 knockout mice to study the function of the Arp2/3 complex in the epidermis.We found that depletion of the Arp2/3 complex by knockout of arpc4 results in skin abnormalities at birth that evolve into a severe psoriasis-like disease hallmarked by hyperactivation of transcription factor Nrf2. Knockout of arpc4 in cultured keratinocytes was sufficient to induce nuclear accumulation of Nrf2, upregulation of Nrf2-target genes and decreased filamentous actin levels. Furthermore, pharmacological inhibition of the Arp2/3 complex unmasked the role of branched actin filaments in Nrf2 regulation. Consistently, we unveiled that Nrf2 associates with the actin cytoskeleton in cells and binds to filamentous actin in vitro Finally, we discovered that Arpc4 is downregulated in both human and mouse psoriatic epidermis. Thus, the Arp2/3 complex affects keratinocytes'' shape and transcriptome through an actin-based cell-autonomous mechanism that influences epidermal morphogenesis and homeostasis. Overall design: Gene expression profile of wt and ARPC4 ko epidermis
Knockout of the Arp2/3 complex in epidermis causes a psoriasis-like disease hallmarked by hyperactivation of transcription factor Nrf2.
Specimen part, Cell line, Subject
View SamplesArp2/3 complex assembles branched actin filaments key to many cellular processes, but its organismal roles remain poorly understood. Here we employed conditional arpc4 knockout mice to study the function of the Arp2/3 complex in the epidermis.We found that depletion of the Arp2/3 complex by knockout of arpc4 results in skin abnormalities at birth that evolve into a severe psoriasis-like disease hallmarked by hyperactivation of transcription factor Nrf2. Knockout of arpc4 in cultured keratinocytes was sufficient to induce nuclear accumulation of Nrf2, upregulation of Nrf2-target genes and decreased filamentous actin levels. Furthermore, pharmacological inhibition of the Arp2/3 complex unmasked the role of branched actin filaments in Nrf2 regulation. Consistently, we unveiled that Nrf2 associates with the actin cytoskeleton in cells and binds to filamentous actin in vitro Finally, we discovered that Arpc4 is downregulated in both human and mouse psoriatic epidermis. Thus, the Arp2/3 complex affects keratinocytes'' shape and transcriptome through an actin-based cell-autonomous mechanism that influences epidermal morphogenesis and homeostasis. Overall design: Gene expression profile of wt, ARPC4 ko and EGFP-Nrf2 expressing keratinocytes.
Knockout of the Arp2/3 complex in epidermis causes a psoriasis-like disease hallmarked by hyperactivation of transcription factor Nrf2.
Specimen part, Cell line, Subject
View SamplesPRC, a member of the PGC-1 coactivator family, is responsive to serum growth factors and up regulated in proliferating cells. Here, we investigated its in vivo role by stably silencing PRC expression with two different short hairpin RNAs (shRNA#1 and shRNA#4) that were lentivirally introduced into U2OS cells. ShRNA#1 transductants exhibited nearly complete knockdown of PRC protein whereas shRNA#4 transductants expressed PRC protein at approximately 15 percent of the control level. Complete PRC silencing by shRNA#1 resulted in a severe inhibition of respiratory growth, reduced expression of respiratory protein subunits from complexes I, II, III and IV, markedly lower complex I and IV respiratory enzyme levels and diminished mitochondrial ATP production. Surprisingly, shRNA#1 transductants exhibited a striking proliferation of abnormal mitochondria that were devoid of organized cristae and displayed severe membrane abnormalities. Although shRNA#4 transductants had normal respiratory subunit expression and a moderately diminished respiratory growth rate, both transductants showed markedly reduced growth on glucose accompanied by inhibition of G1/S cell cycle progression. Microarray analysis revealed striking overlaps in the genes affected by PRC silencing in the two transductants and the functional identities of these overlapping genes were consistent with the observed mitochondrial and cell growth phenotypes. The consistency between phenotype and PRC expression levels in the two independent transductant lines argues that the defects result from PRC silencing and not from off target effects. These results support a role for PRC in the integration of pathways directing mitochondrial respiratory function and cell growth.
Short hairpin RNA-mediated silencing of PRC (PGC-1-related coactivator) results in a severe respiratory chain deficiency associated with the proliferation of aberrant mitochondria.
No sample metadata fields
View SamplesAncestral environmental exposures that promote epigenetic transgenerational inheritance influence all aspects of an individuals life history. Stress experienced during adolescence can affect adult physiological and behavioural phenotypes. The current study utilized a systems biology approach to investigate the interactions of these two forms of epigenetic modification, one carried in the germline transgenerationally and the other contained in the context of life history. A transgenerational epigenetic imprint left by the fungicide vinclozolin promoted regional specific brain gene networks that influenced chronic restraint stress responses to alter adult physiological, brain and behavioural phenotypes. The environmentally-induced epigenetic transgenerational inheritance was found to interact with early life stress response to impact the adult brain genome activity to bring the phenotype into being.
Epigenetic transgenerational inheritance of altered stress responses.
Sex, Specimen part
View SamplesTriplicate experiments from T98G cells under asynchronously growing, and growth arrest by serum deprivation and contact inhibition.
A common set of gene regulatory networks links metabolism and growth inhibition.
No sample metadata fields
View SamplesSleep and affective behaviors are highly interrelated phenotypes, commonly altered in a variety of neuropsychiatric diseases, including major depressive disorder (MDD). To understand the transcriptomic organization underlying sleep and affective function, we studied a population of (C57BL/6J x 129S1/SvImJ) F2 mice by measuring 283 affective and sleep phenotypes and profiling gene expression across four brain regions, including the frontal cortex, hippocampus, thalamus, and hypothalamus. We identified converging molecular bases for sleep and affective phenotypes at both the single-gene and gene-network levels. Utilizing publicly available transcriptomic datasets collected from sleep-deprived mice and major depressive disorder (MDD) patients, we identified three cortical gene networks altered by sleep/wake changes and depression. The network-level actions of sleep loss and depression were opposite to each other, providing a mechanistic basis for the sleep disruptions commonly observed in depression as well as the reported acute antidepressant effects of sleep deprivation. We highlight one particular network composed of circadian rhythm regulators and neuronal activity-dependent immediate-early genes. The key upstream driver of this network, Arc, may act as a nexus linking sleep and depression. Our data provide mechanistic insights into the role of sleep in affective function and MDD.
Cross-species systems analysis identifies gene networks differentially altered by sleep loss and depression.
Sex, Specimen part
View SamplesAlternative splicing is a key event to human transcriptome and proteome diversity and complexity. Recent evidence suggests that pancreatic cancer might possess particular patterns of splice variation that influence the function of individual genes contributing to tumour progression in this disease. The identification of new pancreatic cancer-associated splice variants would offer opportunities for novel diagnostics and potentially also represent novel therapeutic targets.
Splice variants as novel targets in pancreatic ductal adenocarcinoma.
Sex, Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A multi-gene signature predicts outcome in patients with pancreatic ductal adenocarcinoma.
Sex, Age, Specimen part
View SamplesAlternative splicing is a key event to human transcriptome and proteome diversity and complexity. Recent evidence suggests that pancreatic cancer might possess particular patterns of splice variation that influence the function of individual genes contributing to tumour progression in this disease. The identification of new pancreatic cancer-associated splice variants would offer opportunities for novel diagnostics and potentially also represent novel therapeutic targets.
A multi-gene signature predicts outcome in patients with pancreatic ductal adenocarcinoma.
Sex, Age, Specimen part
View SamplesDisuse atrophy is a common clinical phenomenon which significantly impacts muscle function and activities of daily living. In this study, we did expression profiling to identify transcriptional pathways associated with muscle remodeling in a clinical model of disuse.
Transcriptional pathways associated with skeletal muscle disuse atrophy in humans.
Disease, Disease stage
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