Hearing loss is most commonly caused by the destruction of mechanosensory hair cells in the ear. This condition is usually permanent: Despite the presence of putative hair-cell progenitors in the cochlea, hair cells are not naturally replenished in adult mammals. Unlike those of the mammalian ear, the progenitor cells of nonmammalian vertebrates can regenerate hair cells through- out life. The basis of this difference remains largely unexplored but may lie in molecular dissimilarities that affect how progenitors respond to hair-cell death.
Dynamic gene expression by putative hair-cell progenitors during regeneration in the zebrafish lateral line.
Specimen part
View SamplesCaloric restriction (CR) without malnutrition is one of the most consistent strategies for increasing mean and maximal lifespan and delaying the onset of age-associated diseases. Stress resistance is a common trait of many long-lived mutants and life-extending interventions, including CR. Indeed, better protection against heat shock and other genotoxic insults have helped explain the pro-survival properties of CR. In this study, both in vitro and in vivo responses to heat shock were investigated using two different models of CR. Murine B16F10 melanoma cells treated with serum from CR-fed rats showed lower proliferation, increased tolerance to heat shock and enhanced HSP-70 expression, compared to serum from ad libitum-fed animals. Similar effects were observed in B16F10 cells implanted subcutaneously in male C57BL/6 mice subjected to CR. Microarray analysis identified a number of genes and pathways whose expression profile were similar in both models. These results suggest that the use of an in vitro model could be a good alternative to study the mechanisms by which CR exerts its anti-tumorigenic effects.
Caloric restriction induces heat shock response and inhibits B16F10 cell tumorigenesis both in vitro and in vivo.
Cell line, Treatment
View SamplesPolycomb group (PcG) proteins bind to and repress genes in embryonic stem cells and through lineage commitment to the terminal differentiated state. PcG repressed genes are commonly characterized by the presence of the epigenetic histone mark, H3K27me3, catalyzed by the Polycomb repressive complex 2. Here, we present in vivo evidence for a previously unrecognized plasticity of PcG-repressed genes in terminal differentiated brain neurons of parkisonian mice. We show that acute administration of the dopamine precursor, L-DOPA, induces a remarkable increase in H3K27me3S28 phosphorylation. The induction of the H3K27me3S28p histone mark specifically occurs in medium spiny neurons expressing the dopamine D1 receptors and is dependent on Msk1 kinase activity and DARPP-32-mediated inhibition of protein phosphatase-1. Chromatin immunoprecipitation (ChIP) experiments showed that increased H3K27me3S28p was accompanied by reduced PcG binding to regulatory regions of genes. An analysis of the genome wide distribution of L-DOPA induced H3K27me3S28 phosphorylation by ChIP sequencing (ChIP-seq) in combination with expression analysis by RNA-sequencing (RNA-seq) showed that the induction of H3K27me3S28p correlated with increased expression of a subset of PcG repressed genes. We found that induction of H3K27me3S28p persisted during chronic L-DOPA administration to parkisonian mice and correlated with aberrant gene expression. We propose that dopaminergic transmission can activate PcG repressed genes in the adult brain and thereby contribute to long-term maladaptive responses including the motor complications, or dyskinesia, caused by prolonged administration of L-DOPA in Parkinsons disease. Overall design: 12 mice were used for RNAseq, 4 conditions, 3 mice per condition.
Dopamine signaling leads to loss of Polycomb repression and aberrant gene activation in experimental parkinsonism.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Survival transcriptome in the coenzyme Q10 deficiency syndrome is acquired by epigenetic modifications: a modelling study for human coenzyme Q10 deficiencies.
Sex, Age, Specimen part, Treatment, Subject
View SamplesCoenzyme Q10 deficiency syndrome includes a clinically heterogeneous group of mitochondrial diseases characterized by low content of CoQ10 in tissues. The only currently available treatment is supplementation with CoQ10, which improves the clinical phenotype in some patients but does not reverse established damage. We analyzed the transcriptome profiles of fibroblasts from different patients irrespective of the genetic origin of the disease. These cells showed a survival genetic profile apt at maintaining growth and undifferentiated phenotype, promoting anti-apoptotic pathways, and favoring bioenergetics supported by glycolysis and low lipid metabolism. WE conclude that the mitochondrial dysfunction caused byCoQ10 deficiency induces a stable survival adaptation of somatic cells from patients.
Survival transcriptome in the coenzyme Q10 deficiency syndrome is acquired by epigenetic modifications: a modelling study for human coenzyme Q10 deficiencies.
Sex, Specimen part, Treatment
View SamplesCoenzyme Q10 deficiency syndrome includes a clinically heterogeneous group of mitochondrial diseases characterized by low content of CoQ10 in tissues. The only currently available treatment is supplementation with CoQ10, which improves the clinical phenotype in some patients but does not reverse established damage.
Survival transcriptome in the coenzyme Q10 deficiency syndrome is acquired by epigenetic modifications: a modelling study for human coenzyme Q10 deficiencies.
Sex, Age, Treatment, Subject
View SamplesThe mammalian RNA-binding protein AUF1 (AU-binding factor 1, also known as heterogeneous nuclear ribonucleoprotein D, hnRNP D) binds to numerous mRNAs and influences their post-transcriptional fate. Given that many AUF1 target mRNAs encode muscle-specific factors, we investigated the function of AUF1 in skeletal muscle differentiation. In mouse C2C12 myocytes, where AUF1 levels rise at the onset of myogenesis and remain elevated throughout myocyte differentiation into myotubes, RIP (RNP immunoprecipitation) analysis indicated that AUF1 binds prominently to Mef2c (myocyte enhancer factor 2c) mRNA, which encodes the key myogenic transcription factor Mef2c. By performing mRNA half-life measurements and polysome distribution analysis, we found that AUF1 associated with the 3UTR of Mef2c mRNA and promoted Mef2c translation without affecting Mef2c mRNA stability. In addition, AUF1 promoted Mef2c gene transcription via a lesser-known role of AUF1 in transcriptional regulation. Importantly, lowering AUF1 delayed myogenesis, while ectopically restoring Mef2c expression levels partially rescued the impairment of myogenesis seen after reducing AUF1 levels. We propose that Mef2c is a key effector of the myogenesis program promoted by AUF1.
RNA-binding protein AUF1 promotes myogenesis by regulating MEF2C expression levels.
Sex, Specimen part, Cell line, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Calorie restriction in humans inhibits the PI3K/AKT pathway and induces a younger transcription profile.
Specimen part
View SamplesWith the population of older and overweight individuals on the rise in the Western world, there is an ever greater need to slow the aging processes and reduce the burden of age-associated chronic disease that would significantly improve the quality of human life and reduce economic costs. Caloric restriction (CR), is the most robust and reproducible intervention known to delay aging and to improve healthspan and lifespan across species (1); however, whether this intervention can extend lifespan in humans is still unknown. Here we report that rats and humans exhibit similar responses to long-term CR at both the physiological and molecular levels. CR induced broad phenotypic similarities in both species such as reduced body weight, reduced fat mass and increased the ratio of muscle to fat. Likewise, CR evoked similar species-independent responses in the transcriptional profiles of skeletal muscle. This common signature consisted of three key pathways typically associated with improved health and survival: IGF-1/insulin signaling, mitochondrial biogenesis and inflammation. To our knowledge, these are the first results to demonstrate that long-term CR induces a similar transcriptional profile in two very divergent species, suggesting that such similarities may also translate to lifespan-extending effects in humans as is known to occur in rodents. These findings provide insight into the shared molecular mechanisms elicited by CR and highlight promising pathways for therapeutic targets to combat age-related diseases and promote longevity in humans.
Calorie restriction in humans inhibits the PI3K/AKT pathway and induces a younger transcription profile.
No sample metadata fields
View SamplesPurpose : The goal of this study was to use RNA Seq to explore the correlation of gene expression of a collection of clinical P. aeruginosa isolates to various phenotypes, such as antimicrobial resistance, biofilm formation or virulence Methods : mRNA profiles were generated for Pseudomonas aerugionsa clinical samples derived from various geographical locations by deep sequencing. The removal of ribosomal RNA was performed using the Ribo-Zero Bacteria Kit (Illumina) and cDNA libraries were generated with the ScriptSeq v2 Kit (Illumina) . The samples were sequenced in single end mode on an Illumina HiSeq 2500 device and mRNA reads were trimmed and mapped to the NC_008463.1 (PA14) reference genome from NCBI using Stampy pipeline with defaut settings. Overall design: mRNA profiles from Pseudomonas aeruginosa derived from liquid LB cultures grown to an OD600 = 2 and deep sequenced using Illumina HiSeq 2500.
Predicting antimicrobial resistance in Pseudomonas aeruginosa with machine learning-enabled molecular diagnostics.
Disease, Subject
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