This SuperSeries is composed of the SubSeries listed below.
A gene regulatory network anchored by LIM homeobox 1 for embryonic head development.
Specimen part
View SamplesDevelopment of the embryonic head is driven by the activity of gene regulatory networks of transcription factors. LHX1 is a homeobox transcription factor that plays an essential role in the formation of the embryonic head. The loss of Lhx1 function results in anterior truncation of the embryo caused by the disruption of morphogenetic movement of tissue precursors and the dysregulation of WNT signaling activity. Profiling the gene expression pattern in the Lhx1 mutant embryo revealed that tissues in anterior germ layers acquire posterior tissue characteristics, suggesting Lhx1 activity is required for the allocation and patterning of head precursor tissues. Here, we used LHX1 as an entry point to delineate its transcriptional targets and interactors and construct a LHX1-anchored gene regulatory network. Using a gain-of-function approach, we identified genes that immediately respond to Lhx1 activation. Meta-analysis of the datasets of LHX1-responsive genes and genes expressed in the anterior tissues of mouse embryos at head-fold stage, in conjunction with published Xenopus embryonic LHX1 (Xlim1) ChIP-seq data, has pinpointed the putative transcriptional targets of LHX1 and an array of genetic determinants functioning together in the formation of the mouse embryonic head. Overall design: Total RNA obtained from FLAG-Lhx1 and FLAG-Lhx1 mutant embryoid bodies differentiated over 2 days with or without doxycycline treatment for 16 hours. There are three replicates per condition.
A gene regulatory network anchored by LIM homeobox 1 for embryonic head development.
Specimen part, Subject
View SamplesDevelopment of the embryonic head is driven by the activity of gene regulatory networks of transcription factors. LHX1 is a homeobox transcription factor that plays an essential role in the formation of the embryonic head. The loss of Lhx1 function results in anterior truncation of the embryo caused by the disruption of morphogenetic movement of tissue precursors and the dysregulation of WNT signaling activity. Profiling the gene expression pattern in the Lhx1 mutant embryo revealed that tissues in anterior germ layers acquire posterior tissue characteristics, suggesting Lhx1 activity is required for the allocation and patterning of head precursor tissues. Here, we used LHX1 as an entry point to delineate its transcriptional targets and interactors and construct a LHX1-anchored gene regulatory network. Using a gain-of-function approach, we identified genes that immediately respond to Lhx1 activation. Meta-analysis of the datasets of LHX1-responsive genes and genes expressed in the anterior tissues of mouse embryos at head-fold stage, in conjunction with published Xenopus embryonic LHX1 (Xlim1) ChIP-seq data, has pinpointed the putative transcriptional targets of LHX1 and an array of genetic determinants functioning together in the formation of the mouse embryonic head.
A gene regulatory network anchored by LIM homeobox 1 for embryonic head development.
Specimen part
View SamplesTamoxifen injection injures the mouse stomach, triggering a plastic regenerative response termed Spasmolytic Polypeptide Exressing Metaplasia. We are probing how tamoxifen treated stomachs differ from healthy controls, and also how injected rapamycin affects this process
Regenerative proliferation of differentiated cells by mTORC1-dependent paligenosis.
Specimen part
View SamplesProliferation of the self-renewing epithelium of the gastric corpus occurs almost exclusively in the isthmus of the glands, from where cells migrate bi-directionally towards pit and base. The isthmus is therefore generally viewed as the stem cell zone. We find that the stem cell marker Troy is expressed at the gland base by a small subpopulation of chief cells. By lineage tracing using a Troy-eGFP-ires-CreERT2 allele, single marked cells are shown to generate entirely labeled gastric units over periods of months. This phenomenon accelerates upon tissue damage. Troy+ chief cells can be cultured to generate long-lived gastric organoids. Troy marks a specific, 'plastic' subset of differentiated chief cells capable of replenishing entire gastric units, essentially serving as a quiescent reserve stem cell.
Differentiated Troy+ chief cells act as reserve stem cells to generate all lineages of the stomach epithelium.
Specimen part
View SamplesCells were treated with Rakicidin A or an analogue compound BE-43547 or DMSO (control) in three replicates. Overall design: three groups in triplicates.
APD-Containing Cyclolipodepsipeptides Target Mitochondrial Function in Hypoxic Cancer Cells.
Specimen part, Cell line, Subject
View SamplesTranscription factor pancreatic and duodenal homeobox 1 (Pdx1) plays an essential role in the pancreas to regulate its development and maintain proper islet function. However, less is known about the function of Pdx1 in the small intestine.
Expression profiling identifies novel gene targets and functions for Pdx1 in the duodenum of mature mice.
Sex, Age
View SamplesIsocitrate dehydrogenase 1 mutations drive human gliomagenesis, probably through neomorphic enzyme activity that produces D-2-hydroxyglutarate. To model this disease, we conditionally expressed Idh1R132H in the subventricular zone (SVZ) of the adult mouse brain. The mice developed hydrocephalus and grossly dilated lateral ventricles, with accumulation of 2-hydroxyglutarate and reduced -ketoglutarate. Stem and transit amplifying/progenitor cell populations were expanded, and proliferation increased.Cells expressing SVZ markers infiltrated surrounding brain regions. SVZ cells also gave rise to proliferative subventricular nodules. DNA methylation was globally increased, while hydroxymethylation was decreased. Mutant SVZ cells over-expressed Wnt, cell cycle and stem cell genes, and shared an expression signature with human gliomas. Idh1R132H mutation in the major adult neurogenic stem cell niche causes a phenotype resembling gliomagenesis. Isocitrate dehydrogenase 1 mutations drive human gliomagenesis, probably through neomorphic enzyme activity that produces D-2-hydroxyglutarate. To model this disease, we conditionally expressed Idh1R132H in the subventricular zone (SVZ) of the adult mouse brain. The mice developed hydrocephalus and grossly dilated lateral ventricles, with accumulation of 2-hydroxyglutarate and reduced -ketoglutarate. Stem and transit amplifying/progenitor cell populations were expanded, and proliferation increased. Cells expressing SVZ markers infiltrated surrounding brain regions. SVZ cells also gave rise to proliferative subventricular nodules. DNA methylation was globally increased, while hydroxymethylation was decreased. Mutant SVZ cells over-expressed Wnt, cell cycle and stem cell genes, and shared an expression signature with human gliomas. Idh1R132H mutation in the major adult neurogenic stem cell niche causes a phenotype resembling gliomagenesis.
Expression of Idh1<sup>R132H</sup> in the Murine Subventricular Zone Stem Cell Niche Recapitulates Features of Early Gliomagenesis.
Sex, Age, Specimen part
View SamplesThe normally virulent type-I RH parasite is rendered avirulent when lacking ROP5. The avirulent phenotype is a consequence of interaction with the host innate immune system. We sought to understand if ROP5 alters host gene expression in order to escape host defenses. We saw no gene expression differences between host cells infected with wt (RHku80) or RHku80rop5 parasites. We have included uninfected HFF samples that were harvested in parallel with the infected samples.
The polymorphic pseudokinase ROP5 controls virulence in Toxoplasma gondii by regulating the active kinase ROP18.
Specimen part
View SamplesWith aging, significant changes in circadian rhythms occur, including a shift in phase toward a morning chronotype and a loss of rhythmicity in circulating hormones. However, the effects of aging on molecular rhythms in the human brain have remained elusive. Here we employed a previously-described time-of-death analyses to identify transcripts throughout the genome that have a significant circadian rhythm in expression in the human prefrontal cortex (Brodmanns areas (BA) 11 and 47). Expression levels were determined by microarray analysis in 146 individuals. Rhythmicity in expression was found in ~10% of detected transcripts (p<0.05). Using a meta-analysis across the two brain areas, we identified a core set of 235 genes (q<0.05) with significant circadian rhythms of expression. These 235 genes showed 92% concordance in the phase of expression between the two areas. In addition to the canonical core circadian genes, a number of other genes were found to exhibit rhythmic expression in the brain. Notably, we identified more than one thousand genes (1186 in BA11; 1591 in BA47) that exhibited age-dependent rhythmicity or alterations in rhythmicity patterns with aging. Interestingly, a set of transcripts gained rhythmicity in older individuals, which may represent a compensatory mechanism due to a loss of canonical clock function. Thus, we confirm that rhythmic gene expression can be reliably measured in human brain and identified for the first time significant changes in molecular rhythms with aging that may contribute to altered cognition, sleep and mood in later life.
Effects of aging on circadian patterns of gene expression in the human prefrontal cortex.
Sex, Age, Specimen part, Race
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