Muscle denervation due to injury, disease or aging results in impaired motor function. Restoring neuromuscular communication requires axonal regrowth and regeneration of neuromuscular synapses. Muscle activity inhibits neuromuscular synapse regeneration. The mechanism by which muscle activity regulates regeneration of synapses is poorly understood. Dach2 and Hdac9 are activity-regulated transcriptional co-repressors that are highly expressed in innervated muscle and suppressed following muscle denervation. Here, we report that Dach2 and Hdac9 inhibit regeneration of neuromuscular synapses. Importantly, we identified Myog and Gdf5 as muscle-specific Dach2/Hdac9-regulated genes that stimulate neuromuscular regeneration in denervated muscle. Interestingly, Gdf5 also stimulates presynaptic differentiation and inhibits branching of regenerating neurons. Finally, we found that Dach2 and Hdac9 suppress miR206 expression, a microRNA involved in enhancing neuromuscular regeneration. Overall design: RNAseq on innervated and 3 day denervated adult soleus muscle from wildtype mice is compared with that from 3 day denervated soleus muscle from Dach2/Hdac9 deleted mice to identify Dach2/Hdac9-regulated genes.
Dach2-Hdac9 signaling regulates reinnervation of muscle endplates.
No sample metadata fields
View SamplesTissue resident macrophages are functionally diverse cells that share an embryonic mesodermal origin. However, the mechanism(s) that control their specification remain unclear. We performed transcriptional, molecular and in situ spatio-temporal analyses of macrophage development in mice. We report that Erythro-Myeloid Progenitors generate pre-macrophages (pMacs) that simultaneously colonize the head and caudal embryo from embryonic day (E)9.5 in a chemokine-receptor dependent manner, to further differentiate into tissue F4/80+ macrophages. The core macrophage transcriptional program initiated in pMacs, is rapidly diversified in early macrophages as expression of transcriptional regulators becomes tissue-specific. For example, the preferential expression of the transcriptional regulator Id3 initiated in early fetal liver macrophages appears critical for Kupffer cell differentiation, as inactivation of Id3 causes a selective Kupffer cell deficiency that persists in adults. We propose that colonization of developing tissues by differentiating macrophages is immediately followed by their specification as they establish residence, hereby generating the macrophage diversity observed in post-natal tissues. Overall design: RNA-sequencing of sorted macrophage cell populations (Mac) and progenitors (EMP, pMac) from various tissues and collected at different time points, including technical and biological replicates
Specification of tissue-resident macrophages during organogenesis.
Specimen part, Subject, Time
View SamplesTissue resident macrophages are functionally diverse cells that share an embryonic mesodermal origin. However, the mechanism(s) that control their specification remain unclear. We performed transcriptional, molecular and in situ spatio-temporal analyses of macrophage development in mice. We report that Erythro-Myeloid Progenitors generate pre-macrophages (pMacs) that simultaneously colonize the head and caudal embryo from embryonic day (E)9.5 in a chemokine-receptor dependent manner, to further differentiate into tissue F4/80+ macrophages. The core macrophage transcriptional program initiated in pMacs, is rapidly diversified in early macrophages as expression of transcriptional regulators becomes tissue-specific. For example, the preferential expression of the transcriptional regulator Id3 initiated in early fetal liver macrophages appears critical for Kupffer cell differentiation, as inactivation of Id3 causes a selective Kupffer cell deficiency that persists in adults. We propose that colonization of developing tissues by differentiating macrophages is immediately followed by their specification as they establish residence, hereby generating the macrophage diversity observed in post-natal tissues. Overall design: RNA-sequencing of sorted macrophage cell populations (Mac) and progenitors (EMP, pMac) from various tissues and collected at different time points, including technical and biological replicates
Specification of tissue-resident macrophages during organogenesis.
Specimen part, Subject, Time
View SamplesThe aim of this study was to identify differential gene expression in lung T cell subsets upon germline Serpinb1a ablation.
SerpinB1 regulates homeostatic expansion of IL-17+ γδ and CD4+ Th17 cells.
Specimen part
View SamplesThymic epithelial cells (TECs) are essential for thymopoiesis and form a complex three-dimensional network, the organization of which is strikingly different from other epithelia. Interestingly, TECs express simple epithelia keratins in the cortex, stratified epithelia keratins in the medulla and epidermal differentiation markers in Hassall's bodies. Here we investigate the relationship between thymic epithelium and epidermal differentiation and show that the thymus of the rat contains a population of clonogenic TECs that can be extensively cultured and cloned using conditions developed for epidermal cell therapy in human. Clonogenic TECs conserve a thymic identity and the capacity to integrate in a thymic epithelial network, but they acquire new functionalities when exposed to an inductive skin microenvironment, permanently adopting the fate of hair follicle multipotent stem cells. This change in fate, maintained over time in serial transplantation, correlates with a down-regulation of transcription factors important for thymic identity, and an up-regulation of epidermal markers. Consequently, the TECs capacity to integrate in a thymic epithelial network is altered or even lost. Our results demonstrate that the thymus contains a population of holoclone-like epithelial cells that can function as bona fide multipotent keratinocyte stem cells, and that microenvironmental cues are sufficient to re-direct epithelial-cell fate, allowing crossing of primitive germ layer boundaries from endoderm to ectoderm.
Microenvironmental reprogramming of thymic epithelial cells to skin multipotent stem cells.
No sample metadata fields
View SamplesRhomboid family protein RHBDF2, an upstream regulator of the epidermal growth factor (EGF) receptor signaling, has been implicated in cutaneous wound healing. However, the underlying molecular mechanisms are still emerging. Using a gain-of-function mutation in the mouse Rhbdf2 gene (Rhbdf2cub/cub), which shows a regenerative phenotype, we sought to identify the underlying mechanism.
Early induction of NRF2 antioxidant pathway by RHBDF2 mediates rapid cutaneous wound healing.
Specimen part, Treatment, Time
View SamplesRNA-binding proteins (RBPs) are critical regulators of gene expression and elucidating the interactions of RBPs with their RNA targets is necessary to understand how combinations of RBPs control transcriptome expression. The Quaking-related (QR) sub-family of STAR domain RBPs includes developmental regulators and tumor suppressors such as C. elegans GLD-1, which functions as a master regulator of germ line development. To understand how GLD-1 interacts with the transcriptome, we identified GLD-1 associated mRNAs by a ribonomic approach. The scale of GLD-1 mRNA interactions allowed us to determine rules governing GLD-1 target selection and to derive a predictive model where GLD-1 association with mRNA is based on the number and strength of 7-mer GLD-1 binding elements (GBEs) within UTRs. GLD-1/mRNA interactions were quantified, and predictions were verified both in vitro and in live animals, including by transplantation experiments where weak and strong GBEs imposed translational repression of increasing strength on a non-target mRNA.Importantly, this study provides a unique quantitative picture of how an RBP interacts with its mRNA targets. As combinatorial regulation by multiple RBPs is thought to regulate gene expression, quantification of RBP/mRNA interactions should be a way to predict and potentially modify biological outcomes of complex posttranscriptional regulatory networks, and our analysis suggests that such an approach is possible.
A quantitative RNA code for mRNA target selection by the germline fate determinant GLD-1.
Specimen part
View SamplesThe heat shock response (HSR) is a mechanism to cope with proteotoxic stress by inducing the expression of molecular chaperones and other heat shock response genes. The HSR is evolutionarily well conserved and has been widely studied in bacteria, cell lines and lower eukaryotic model organisms. However, mechanistic insights into the HSR in higher eukaryotes, in particular in mammals, are limited. We have developed an in vivo heat shock protocol to analyze the HSR in mice and dissected heat shock factor 1 (HSF1)-dependent and -independent pathways. Whilst the induction of proteostasis-related genes was dependent on HSF1, the regulation of circadian function related genes, indicating that the circadian clock oscillators have been reset, was independent of its presence. Furthermore, we demonstrate that the in vivo HSR is impaired in mouse models of Huntington's disease but we were unable to corroborate the general repression of transcription after a heat shock found in lower eukaryotes. Overall design: RNA-Seq was performed on mRNA isolated from quadriceps femoris muscle of 24 mice. These mice were of wild type, R6/2, and Hsf1-/- genotypes. Two mice of each genotype were tested in four conditions: (1) heat shock, (2) control heat shock, (3) HSP90 inhibition (NVP-HSP990), and (4) HSP90 inhibition vehicle.
HSF1-dependent and -independent regulation of the mammalian in vivo heat shock response and its impairment in Huntington's disease mouse models.
Age, Specimen part, Treatment, Subject
View SamplesThe goal of this study was to assess whether the presence of HLA-B*35 contributes to activation of ER stress/UPR and inflammation in lcSScPAH PBMC.
The HLA-B*35 allele modulates ER stress, inflammation and proliferation in PBMCs from Limited Cutaneous Systemic Sclerosis patients.
Specimen part
View SamplesGene expression profiling was carried out on primary ovarian carcinomas from 10 patients. The primary research question is whether gene expression differs in tissues from individuals with high vs low symptoms of psychological depression.
Depression, social support, and beta-adrenergic transcription control in human ovarian cancer.
No sample metadata fields
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