The aim of this work was to produce a reproducible molecular signature of human muscle responses to resistance training and examine how such a profile relates to new and established exercise adaptation gene networks.
Molecular networks of human muscle adaptation to exercise and age.
Age, Specimen part, Subject, Time
View SamplesThe overall objective of the heritage project is to study the role of the genotype in cardiovascular,metabolic and hormonal responses to aerobic exercise training and the contribution of regular exercise to changes in several cardiovascular disease and diabetes risk factors.
Molecular networks of human muscle adaptation to exercise and age.
Age, Specimen part, Subject, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A transcriptional map of the impact of endurance exercise training on skeletal muscle phenotype.
Sex
View SamplesThe molecular pathways which are activated and contribute to physiological remodeling of skeletal muscle in response to endurance exercise have not been fully characterized. We previously reported that ~800 gene transcripts are regulated following 6 weeks of supervised endurance training in young sedentary males, referred to as the training responsive transcriptome (TRT). Here we utilized this database together with data on biological variation in muscle adaptation to aerobic endurance training in both humans and a novel out-bred rodent model to study the potential regulatory molecules that coordinate this complex network of genes. We identified three DNA sequences representing RUNX1, SOX9, and PAX3 transcription factor binding sites as over-represented in the TRT. In turn, miRNA profiling indicated that several miRNAs targeting RUNX1, SOX9 and PAX3 were down-regulated by endurance training. The TRT was then examined by contrasting subjects who demonstrated the least vs. the greatest improvement in aerobic capacity (low vs. high responders), and at least 100 of the 800 TRT genes were differentially regulated, thus suggesting regulation of these genes may be important for improving aerobic capacity. In high responders, pro-angiogenic and tissue developmental networks emerged as key candidates for coordinating tissue aerobic adaptation. Beyond RNA level validation there were several DNA variants that associated with VO(2)max trainability in the HERITAGE Family Study but these did not pass conservative Bonferroni adjustment. In addition, in a rat model selected across 10 generations for high aerobic training responsiveness, we found that both the TRT and a homologous subset of the human high responder genes were regulated to a greater degree in high responder rodent skeletal muscle. This analysis provides a comprehensive map of the transcriptomic features important for aerobic exercise-induced improvements in maximal oxygen consumption.
A transcriptional map of the impact of endurance exercise training on skeletal muscle phenotype.
Sex
View SamplesMutations in the PTEN, TP53 and RB1 pathways are obligate events in the pathogenesis of human glioblastomas, the highest grade of astrocytoma. To investigate synergy between these tumor suppressors in mice, we induced various combinations of compound deletions conditionally in astrocytes and neural precursors in the mature brain. The resulting highly penetrant astrocytomas showed a spectrum of histopathological variation reminiscent of human tumors, and ranged from grade III to grade IV (glioblastoma). Secondary somatic mutations varied depending on the combination of initiating deletions and were relevant to human disease. Receptor tyrosine kinase amplifications were frequent in tumors initiated by combined conditional deletion of Pten and Tp53, but not when Rb, Pten and Tp53 were simultaneously deleted. Multiple mutations within PI3K and Rb pathways were acquired, however, Mapk activation was not consistently detected in astrocytomas. Gene expression profiling revealed striking similarities to previously described human astrocytoma subclasses. A subset of astrocytomas initiated outside of proliferative niches in the adult brain.
Cooperativity within and among Pten, p53, and Rb pathways induces high-grade astrocytoma in adult brain.
Sex, Specimen part
View SamplesTo investigate Pten function in neonatal developing brain, we conditionally inactivated Pten in neural stem/progenitor cells at birth using a Nestin-CreER transgenic driver. Pten inactivation created a novel perivascular proliferative niche in the cerebellum that did not progress to malignancy during the lifespan of the mouse. Co-deletion of Pten and Trp53 synergized to cause fully penetrant medulloblastoma originating from a perivascular niche. The Pten and Trp53 double knock-out medulloblastomas showed an extensive and abnormal blood vessel network and advanced neuronal differentiation of tumor cells compared to medulloblastomas arising in Nestin-creER;Trp53fl/fl mice, suggesting that Pten loss promoted angiogenesis and neuronal differentiation in medulloblastoma. EdU pulse-chase experiments demonstrated a lineage hierarchy of the double knock-out medulloblastomas consistent with a perivascular cancer stem cell population. The Pten and Trp53 double knock-out medulloblastomas showed somatic loss of chromosomes 7, 13 and 16, and inactivating mutations in the tumor suppressor gene Ptch1. Gene expression profiles showed that this model recapitulated the subgroup of human medulloblastomas with de-regulated SHH signaling.
PTEN Signaling in the Postnatal Perivascular Progenitor Niche Drives Medulloblastoma Formation.
Sex, Specimen part
View SamplesA conserved molecular pathway has emerged controlling endoderm formation in Xenopus zebrafish and mice. Key genes in this pathway include Nodal ligands and transcription factors of the Mix-like paired homeodomain class, Gata4-6 zinc finger factors and Sox17 HMG domain proteins. While a linear epistatic pathway has been proposed, the precise hierarchical relationships between these factors and their downstream targets are largely unresolved. Here we used a combination of microarray analysis and loss-of-function experiments to examine the global regulatory network controlling Xenopus endoderm formation. We identified over 300 transcripts enriched in the gastrula endoderm, including most of the known endoderm regulators as well as over a hundred uncharacterized genes. Surprisingly only 10% of the endoderm transcriptome is regulated as predicted by the current linear model. We find that Nodals, Mixer and Sox17 have both shared and distinct sets of downstream targets and that a number of unexpected autoregulatory loops exist between Sox17 and Gata4-6, Sox17 and Bix1, 2, 4 and between Sox17 and Xnr4. We find that Mixer does not function primarily via Sox17 as previously proposed. This data provides a new insight into the complexity of endoderm formation and will serve as valuable resource for establishing a complete endoderm gene regulatory network.
Global analysis of the transcriptional network controlling Xenopus endoderm formation.
No sample metadata fields
View SamplesForegut organogenesis is regulated by inductive interactions between the endoderm and the adjacent mesoderm. We identified genes induced in the foregut progenitors by the adjacent mesoderm.
Sizzled-tolloid interactions maintain foregut progenitors by regulating fibronectin-dependent BMP signaling.
Specimen part
View SamplesGroup 3 innate lymphoid cells (ILC3) are composed of NCR- and NCR+ subsets located at mucosal sites exposed to billions of commensal microbes and potentially harmful pathogens. Together with T cells, the various ILC3 subsets maintain the balance between homeostasis and immune activation. Using genetic mapping, we reveal here the existence of a new subset of NCR- ILC3 transiently expressing Ncr1 but strongly related to unlabeled NCR- ILC3, demonstrating previously unsuspected heterogeneity within the NCR- ILC3 population. Notch signaling is required for the differentiation of NCR- ILC3 into NCR+ ILC3. However, we show here that Notch signaling must be sustained for the maintenance of the NCR+ phenotype and that TGF-ß impairs the development of NCR+ ILC3. Thus, ILC3 diversity and the plasticity of the NCR- and NCR+ subsets is regulated by the balance between the opposing effects of Notch and TGF-ß signaling, maintaining homeostasis in the face of continual challenges. Overall design: Transcriptional profiling of three ILC subsets (NCR-FM-, NCR-FM- and NCR+FM+) using RNA sequencing
Transforming growth factor-β and Notch ligands act as opposing environmental cues in regulating the plasticity of type 3 innate lymphoid cells.
Specimen part, Cell line, Subject
View SamplesHESC-H9 and iPSC lines 3.5, 3.6 and 3.12 were analyzed using Affymetrix microarray before and after Definitive Endoderm (DE) formation. DE was induced using the ActivinA differentiation protocol described by D'Amour et al., 2006 (PMID: 16258519) Clustering analysis of transcripts that were differentially regulated during DE formation indicated that iPSC lines 3.5 and 3.12 differentiate in manner that is highly similar to HESC-H9 cells iPSC line 3.6 had a more divergent transcriptional profile.
Directed differentiation of human pluripotent stem cells into intestinal tissue in vitro.
No sample metadata fields
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