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 SamplesHIV-1 nucleoside reverse transcriptase inhibitor (NRTI) use is associated with severe adverse events. However, the exact mechanisms behind their toxicity has not been fully understood. Mitochondrial dysfunction after chronic exposure to NRTIs has predominantly been assigned to mitochondrial polymerase-? inhibition by NRTIs. However, an increasing amount of data suggests that this is not the sole mechanism. Many NRTI induced adverse events have been linked to the incurrence of oxidative stress, although the causality of events leading to reactive oxygen species (ROS) production and their role in toxicity is unclear. In this study we show that short-term effects of these drugs, which are rarely discussed in the literature, include direct inhibition of the mitochondrial respiratory chain (MRC), decreased ATP levels and increased ROS production. Collectively these events affect fitness and longevity of C. elegans through mitohormetic signalling events. Furthermore, we demonstrate that these effects can be normalized by addition of the anti-oxidant N-acetylcysteine (NAC), which suggests that ROS likely influence the onset and severity of adverse events upon drug exposure. Overall design: RNA-seq on Caenorhabditis elegans exposed to DMSO, 3''-azido-3''-deoxythymidine (zidovudine or AZT), 2'',3''-didehydro-2'',3''-deoxythymidine (stavudine or d4T), 3''-deoxy-3''-fluorothymidine (alovudine or FLT) or untreated control after 24 or 72 hours of exposure.
Beyond the polymerase-γ theory: Production of ROS as a mode of NRTI-induced mitochondrial toxicity.
Specimen part, Subject
View SamplesChildhood acute lymphoblastic leukemia (ALL) comprises a large group of genetic subtypes with a favorable prognosis characterized by a TEL-AML1-fusion, hyperdiploidy (>50 chromosomes) or E2A-PBX1 fusion and a smaller group with unfavorable outcome characterized by either a BCR-ABL-fusion, MLL-rearrangement or T-ALL.
A subtype of childhood acute lymphoblastic leukaemia with poor treatment outcome: a genome-wide classification study.
No sample metadata fields
View SamplesChildhood acute lymphoblastic leukemia (ALL) comprises a large group of genetic subtypes with a favorable prognosis characterized by a TEL-AML1-fusion, hyperdiploidy (>50 chromosomes) or E2A-PBX1 fusion and a smaller group with unfavorable outcome characterized by either a BCR-ABL-fusion, MLL-rearrangement or T-ALL.
A subtype of childhood acute lymphoblastic leukaemia with poor treatment outcome: a genome-wide classification study.
No sample metadata fields
View SamplesContext: Despite the well-recognized clinical features due to insufficient or excessive thyroid hormone (TH) levels in humans, it is largely unknown which genes are regulated by TH in human tissues. objective: To study the effect of TH on human gene expression profiles in whole blood, mainly consisting of TRa-expressing cells. Methods: We performed next-generation RNA sequencing on whole blood samples from 8 athyroid patients (4 females) on and after 4 weeks off levothyroxine replacement. Gene expression changes were analyzed through paired differential expression analysis and confirmed in a validation cohort. Weighted gene co-expression network analysis (WGCNA) was applied to identify thyroid state-related networks. Results: We detected 486 differentially expressed (DE) genes (fold-change above 1.5; multiple testing corrected P-value <0.05), of which 76 % were positively and 24 % were negatively regulated. Gene ontology (GO) enrichment analysis revealed that 3 biological processes were significantly overrepresented of which the process translational elongation showed the highest fold enrichment (7.3 fold, P=1.8 x 10-6). Comparative transcriptome analysis revealed significant overlap with DE-genes in muscle samples upon different thyroid state (1.7-fold enrichment; P=0.02). WGCNA analysis independently identified various gene clusters that correlated with thyroid state. Further GO-analysis suggested that thyroid state regulates platelet function. Conclusions: Changes in thyroid state regulate numerous genes in human whole blood, predominantly TRa-expressing leukocytes. In addition, TH may regulate gene expression in platelets. Whole blood samples might potentially be used as a proxy for other TRa-expressing tissues in humans. Overall design: Transcriptome profiling (RNA-Seq) of 8 thyroidectomized human whole blood samples, sequenced first in hypothyroid state and after levothyroxine supplementation sequenced in a hypothyroid (mild thyreotoxic state) state on a Illumina HiSeq 2500 system.
Thyroid State Regulates Gene Expression in Human Whole Blood.
Specimen part, Subject
View SamplesMice of indicated ages and genotypes were perfused and their brains dissected and dissociated. Cells were fixed, immunolabeled and FACS sorted. RNA was extracted from neuron, astrocyte, and microglial cell populations. Typical RIN=4-5 for neurons, 6-8 for astrocytes, and 5-7 for microglia. Typical RNA yields ~100ng for neurons, ~20ng for microglia, and ~10ng for astrocytes. cDNA was generated from up to 25 ng of total RNA using Nugen’s RNA-Seq method for low-input RNA samples, Ovation RNA-Seq System V2 (NuGEN). (Per manufacturers instructions, total RNA was neither depleted of rRNA nor polyA-selected.) 1 µg of sheared cDNA was taken into further processing, starting at end repair step, using Illumina’s TruSeq RNA Sample Preparation Kit v2 (Illumina). The "SAMPLE_ID" sample characteristic is a sample identifier internal to Genentech. The ID of this project in Genentech''s ExpressionPlot database is PRJ0006149 Overall design: Astrocytes, microglia and neurons were sorted from 7- or 13-month old PS2APP or non-transgenic mice, 4 = n = 7 per group.
Untangling the brain's neuroinflammatory and neurodegenerative transcriptional responses.
Age, Specimen part, Subject
View SamplesDiminishment of colonic health is associated with various age-related pathologies. Calorie restriction (CR) is an efficient strategy to increase healthy lifespan, although underlying mechanisms are not fully elucidated. Here we report the effects of lifelong CR on markers of colonic health in aging mice. We show that 30% energy reduction, as compared to a control (C) and moderate-fat (MF) diet, is associated with attenuated immune-related gene expression and lower levels of bile acids in the colon. Pronounced shifts in microbiota composition, together with lowered plasma levels of interleukin 6, in mice exposed to CR are in line with these findings. Furthermore, expression of genes involved in lipid metabolism was higher upon CR as compared to C and MF, pointing towards efficient regulation of energy metabolism. Switching from CR to an ad libitum MF diet at old age revealed remarkable phenotypic plasticity, although expression of a small subset of genes remained CR-associated. This research demonstrates that CR beneficially affects markers of colonic health in aging mice and as such may attenuate the progressive age-related decline in health.
Lifelong calorie restriction affects indicators of colonic health in aging C57Bl/6J mice.
Sex, Specimen part
View SamplesNormal mice were injected i.p. with LPS or saline. 24h later, perfused brains were dissociated. Cells were fixed, immunolabeled and FACS sorted. RNA was extracted from neuron, astrocyte, and microglial cell populations. Typical RIN=4-5 for neurons, 6-8 for astrocytes, and 5-7 for microglia. Typical RNA yields ~100ng for neurons, ~20ng for microglia, and ~10ng for astrocytes. cDNA was generated from up to 25 ng of total RNA using Nugen''s RNA-Seq method for low-input RNA samples, Ovation RNA-Seq System V2 (NuGEN). (Per manufacturers instructions, total RNA was neither depleted of rRNA nor polyA-selected.) 1 µg of sheared cDNA was taken into further processing, starting at end repair step, using Illumina''s TruSeq RNA Sample Preparation Kit v2 (Illumina). The "SAMID" sample characteristic is a sample identifier internal to Genentech. The ID of this project in Genentech''s ExpressionPlot database is PRJ0005404 Overall design: Astrocytes, microglia and neurons were sorted from LPS or saline treated mice. n=4 or 5 per group.
Untangling the brain's neuroinflammatory and neurodegenerative transcriptional responses.
Specimen part, Treatment, Subject
View SamplesRNA was purified from intact cerebrocortical tissue of female PS2APP or non-transgenic mice, perfused at 7 or 13 months of age. The "SAMPLE_ID" sample characteristic is a sample identifier internal to Genentech. The ID of this project in Genentech''s ExpressionPlot database is PRJ0007648 Overall design: RNA from whole cortex of female PS2APP or non-transgenic mice at 7 or 13 months.
Untangling the brain's neuroinflammatory and neurodegenerative transcriptional responses.
Age, Subject
View Samples