A study on the effects of an sdiA mutant and the AHL molecule on the virulence of EHEC
Chemical sensing in mammalian host-bacterial commensal associations.
No sample metadata fields
View SamplesCell fate specification relies on the action of critical transcription factors that become available at distinct stages of embryonic development. One such factor is NeuroD1, which is essential for eliciting the neuronal development program and possesses the ability to reprogram other cell types into neurons. Given this capacity, it is important to understand its targets and the mechanism underlying neuronal specification. Here, we show that NeuroD1 directly binds regulatory elements of neuronal genes that are developmentally silenced by epigenetic mechanisms. This targeting is sufficient to initiate events that confer transcriptional competence, including reprogramming of transcription factor landscape, conversion of heterochromatin to euchromatin and increased chromatin accessibility, indicating potential pioneer factor ability of NeuroD1. The transcriptional induction of neuronal fate genes is maintained via epigenetic memory despite a transient NeuroD1 induction during neurogenesis. Our study not only reveals the NeuroD1-dependent gene regulatory program driving neurogenesis but also increases our understanding of how cell-fate specification during development involves a concerted action of transcription factors and epigenetic mechanisms. Overall design: 1. Ectopic NeuroD1 was induced for 48 hours (+Dox) in ES cells for checking initiation of neuronal transcriptional program in comparison to uninduced condition (-Dox) 2. ChIP-seq was performed after 24 hours of NeuroD1 induction in ES cells.
NeuroD1 reprograms chromatin and transcription factor landscapes to induce the neuronal program.
No sample metadata fields
View SamplesPurpose: Analyze the function of the transcription factors Hand2 and Gata3 in adult sympathetic neurons by induced knockout and RNAseq analysis Overall design: Method and Result: Hand2flx/del::DbhCreERT2 (referred to as mutant) and Hand2flx/+::DbhCreERT2 (referred to a control) were injected for 10 days with tamoxifen to activate Cre. Animals were killed, sympathetic ganglia (SCG+Stellate) collected and processed for RNA isolation and RNAseq (Stanzel et al., 2016). Gata3flx/flx::DbhCerERT2 (mutant) and Gata3flx/+::DbhCreERT2 (controls) were treated as Hand2 animals. 16 ganglia from 4 mice were pooled for Hand2 mutant and controls and Gata3 controls. As only rudimentary ganglia were present in Gata3 mutant mice (Tsarovina et al., 2010) ganglia from 8 mice were pooled. The specific effects of the Hand2 knockout are decribed in Stanzel et al., 2016. The analysis of ganglion rudiments in the Gata3 knockout revealed that Gata3 was not reduced, indicating that the remaining cells had escaped the knockout.
Distinct roles of hand2 in developing and adult autonomic neurons.
Specimen part, Subject
View SamplesAstrocyte responses to neuronal injury may be beneficial or detrimental to neuronal recovery, but the mechanism that determines these different responses are poorly understood. Transcriptional analysis showed that EphB1 induces a protective inflammatory signature in astrocytes, which is distinct from the response evoked by interleukin (IL)-6, which is known to have both pro- and anti-inflammatory properties. We demonstrate that this beneficial EphB1 induced signaling pathway is disrupted in astrocytes derived from human induced pluripotent stem cells (iPSC) of amyotrophic lateral sclerosis (ALS) patients. Overall design: Examination of transcriptome-wide gene expression profiles of purified murine wildtype astrocyte cultures (untreated and treated with IL-6 or EphB1).
A neuroprotective astrocyte state is induced by neuronal signal EphB1 but fails in ALS models.
Specimen part, Cell line, Subject
View SamplesAstrocyte responses to neuronal injury may be beneficial or detrimental to neuronal recovery, but the mechanism that determines these different responses are poorly understood. Transcriptional analysis showed that EphB1 induces a protective inflammatory signature in astrocytes, which is distinct from the response evoked by interleukin (IL)-6, which is known to have both pro- and anti-inflammatory properties. We demonstrate that this beneficial EphB1 induced signaling pathway is disrupted in astrocytes derived from human induced pluripotent stem cells (iPSC) of amyotrophic lateral sclerosis (ALS) patients. Overall design: Examination of transcriptome-wide gene expression profiles of terminally differentiated and enriched iPSC-derived astrocytes harboring the SOD1 D90A mutation
A neuroprotective astrocyte state is induced by neuronal signal EphB1 but fails in ALS models.
Specimen part, Subject
View SamplesEctopic expression of defined transcription factors can force direct cell fate conversion from one lineage to another in the absence of cell division. Several transcription factor cocktails have enabled successful reprogramming of various somatic cell types into induced neurons (iNs) of distinct neurotransmitter phenotype. However, the nature of the intermediate states that drive the reprogramming trajectory towards distinct iN types is largely unknown. Here we show that successful direct reprogramming of adult human brain pericytes into functional iNs by Ascl1 and Sox2 (AS) encompasses transient activation of a neural stem cell-like gene expression program that precedes bifurcation into distinct neuronal lineages. Intriguingly, during this transient state key signaling components relevant for neural induction and neural stem cell maintenance are regulated and functionally contribute to iN reprogramming and maturation. Thus, AS-mediated reprogramming into a broad spectrum of iN types involves the unfolding of a developmental program via neural stem cell-like intermediates. Overall design: Single-cell transcriptomes from multiple time points and conditions during direct conversion of human pericytes into induced pericytes through the overexpression of defined factors. Please note that [1] the *ctrl samples represent mock-transfected cells (analyzed along side of the transfected cells) [2] The cell type (for each sample) is provided as 'pericytes or pericyte-derived induced neuronal cells' (as they are in a differentiation continuum from pericytes to neurons due to the treatment protocol) with the combination of 'genotype/variation' and 'time point' information.
Direct pericyte-to-neuron reprogramming via unfolding of a neural stem cell-like program.
Specimen part, Subject
View SamplesGamma tocotrienol induces apoptosis in breast cancer cells however, the molecular mechanisms are not completely understood.
Gamma-tocotrienol induced apoptosis is associated with unfolded protein response in human breast cancer cells.
Cell line
View SamplesMiR-1246 was found to promote tumorigenesis and metastasis in sevearl cancer types. In the context of tumor microenvironment, tumor-associated macrophages are a central part typically correlated with poor prognosis.
Mutant p53 cancers reprogram macrophages to tumor supporting macrophages via exosomal miR-1246.
Specimen part
View SamplesEpithelial-neuronal signaling is essential for sensory encoding in touch, itch and nociception; however, little is known about the release mechanisms and neurotransmitter receptors through which skin cells govern neuronal excitability. Merkel cells are mechanosensory epidermal cells that have long been proposed to activate neuronal afferents through chemical synaptic transmission. We employed a set of classical criteria for chemical neurotransmission as framework to directly test this hypothesis. RNA sequencing of adult Merkel cells demonstrated that they express presynaptic molecules and biosynthetic machinery for adrenergic transmission. Moreover, live-cell imaging directly demonstrated that Merkel cells mediate activity- and VMAT-dependent release of fluorescent catecholamine neurotransmitter analogues. Touch-evoked firing in Merkel-cell afferents was inhibited either by pre-synaptic silencing of SNARE-mediated vesicle release from Merkel cells or by neuronal deletion of b2-adrenergic receptors. Together, these results identify both pre- and postsynaptic mechanisms through which Merkel cells excite mechanosensory afferents to encode gentle touch. Overall design: RNA-seq of basal keratinocytes and Merkel cells purified with FACS
Merkel Cells Activate Sensory Neural Pathways through Adrenergic Synapses.
Sex, Specimen part, Cell line, Subject
View SamplesPrimary culture airway epithelial cells, grown under physiologic air-liquid interface conditions, with, or without IL-13 in order to study the effects of this cytokine on mucous cell metaplasia, an important feature of asthma and COPD.
IL-13-induced airway mucus production is attenuated by MAPK13 inhibition.
Specimen part
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