Despite the widespread interest in direct neuronal reprogramming, the mechanisms underpinning fate conversion remain largely unknown. Our study revealed a critical time point after which cells either successfully convert into neurons or succumb to cell death. Co-transduction with Bcl-2 greatly improved negotiation of this critical point by faster neuronal differentiation. Surprisingly, mutants with reduced or no affinity for Bax demonstrated that Bcl-2 exerts this effect by an apoptosis-independent mechanism. Consistent with a caspase-independent role, ferroptosis inhibitors potently increased neuronal reprogramming by inhibiting lipid peroxidation occurring during fate conversion. Genome-wide expression analysis confirmed that treatments promoting neuronal reprogramming elicit an anti-oxidative stress response. Importantly, coexpression of Bcl-2 and anti-oxidative treatments lead to an unprecedented improvement in glial-to-neuron conversion after traumatic brain injury in vivo, underscoring the relevance of these pathways in cellular reprograming irrespective of cell type, in vitro and in vivo.
Identification and Successful Negotiation of a Metabolic Checkpoint in Direct Neuronal Reprogramming.
Sex, Specimen part
View SamplesWe report the application of low cell number sequencing of identifiable Drosophila melanogaster neurons following behavior. We demonstate the feasibility of identifying the transcriptome of 5 Mushroom Body output Neurons and 2 classes of Kenyon Cells. We find these neurons display a diverse repertoire of receptors and signaling transcripts. This information alone seems to be enough to identify each class of neurons in the study. In additional we show that aversive long-term memory induces changes in gene transcript levels in a subset of these neurons. This study provides a framework for identifying neuronal classes in Drosophila melanogaster and gaining insight into the interplay between behavior and gene regulation. Overall design: 5 Mushroom Body output neurons and 2 classes of kenyon cells are used to look at general gene expression and changes following aversive long term memory. Paired control and trained animals were used and a minimum of 4 pairs up to 6 pairs. Animals were of the same background (w1118). Animals were aged and parental matched. Cells were harvested at the same chronological time for the animals across all experiments. All animals were exposed to 1 minute of each odor and 1 minute of a series of 12 5second 60V shocks. This was considered one block and then the animals had spaced training of each block so there was a 10 minute break between 8 blocks of training. Trained animals had an odor paired with a shock, control animals received the shock then the odor stimulus. All cells were harvested usign a patch pipet from living animals on an electrophysiology rig within a half hour of the end of training. Cells were amplified using the Clontech SMARTer Ultra Low Input RNA version 2 High Volume kit. 2 Brain samples were also collected and 3-4 whole fly samples for each genotype were collected to account for background differences across flies.
Cell-Type-Specific Transcriptome Analysis in the Drosophila Mushroom Body Reveals Memory-Related Changes in Gene Expression.
Subject
View SamplesBcl11a is a transcription factor known to regulate lymphoid and erythroid development. Recent bioinformatic analysis of global gene expression patterns has suggested a role for Bcl11a in the development of dendritic cell (DC) lineages. We tested this hypothesis by analyzing the development of DC and other lineages in Bcl11a(-/-) mice. We show that Bcl11a is required for expression of IL-7 receptor (IL-7R) and Flt3 in early hematopoietic progenitor cells. The loss of IL-7R(+) common lymphoid progenitors accounts for previously described lymphoid defects in Bcl11a(-/-) mice. In addition, we found severely decreased numbers of plasmacytoid dendritic cells (pDCs) in Bcl11a(-/-) fetal livers and in the bone marrow of Bcl11a(-/-) fetal liver chimeras. Moreover, Bcl11a(-/-) cells show severely impaired in vitro development of Flt3L-derived pDCs and classical DCs (cDCs). In contrast, we found normal in vitro development of DCs from Bcl11a(-/-) fetal liver cells treated with GM-CSF. These results suggest that the persistent cDC development observed in Bcl11a(-/-) fetal liver chimeras reflects derivation from a Bcl11a- and Flt3-independent pathway in vivo.
Bcl11a controls Flt3 expression in early hematopoietic progenitors and is required for pDC development in vivo.
Specimen part
View SamplesThe present study reveals LMYC and MXD1 as novel regulators of a transcriptional program that is modulated during the maturation of Batf3-dependent dendritic cells (also known as type I classical dendritic cells or cDC1s).
The MYCL and MXD1 transcription factors regulate the fitness of murine dendritic cells.
Specimen part
View SamplesES cells differentiated in the presence of the Wnt inhibitor DKK1 fail to express the transcription factor Snail and undergo EMT or mesoderm differentiation. We generated an ES cell line, A2.snail, that induced Snail expression upon addition of doxycycline addition.
Snail promotes the cell-autonomous generation of Flk1(+) endothelial cells through the repression of the microRNA-200 family.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Zbtb46 expression distinguishes classical dendritic cells and their committed progenitors from other immune lineages.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Dual actions of Meis1 inhibit erythroid progenitor development and sustain general hematopoietic cell proliferation.
Specimen part, Treatment
View SamplesThe homeodomain protein Meis1 is essential for definitive hematopoiesis and vascular patterning in the mouse embryo. Meis2, another member of the same family, shares 82% protein identities with Meis1. Our present study suggested Meis2 exerts two distinguishable effects in differentiating ES cells. First, it increases the numbers of hematopoietic progenitors and extends their persistence in culture. Second, Meis2 skews hematopoietic differentiation by suppressing erythroid while enhancing megakaryocytic progenitor differentiation. To identify the underlying transcriptional bases of these actions, we carried out microarray analysis to compare the various populations of cells developing in ES differentiation cultures in the presence and absence of Meis2 induction.
Dual actions of Meis1 inhibit erythroid progenitor development and sustain general hematopoietic cell proliferation.
Specimen part, Treatment
View SamplesThe homeodomain protein Meis1 is essential for definitive hematopoiesis and vascular patterning in the mouse embryo. Our present study suggested it exerts two distinguishable effects in differentiating ES cells. First, it increases the numbers of hematopoietic progenitors and extends their persistence in culture. Second, Meis1 skews hematopoietic differentiation by suppressing erythroid while enhancing megakaryocytic progenitor differentiation. To identify the underlying transcriptional bases of these actions, we carried out microarray analysis to compare the various populations of cells developing in ES differentiation cultures in the presence and absence of Meis1 induction.
Dual actions of Meis1 inhibit erythroid progenitor development and sustain general hematopoietic cell proliferation.
Specimen part, Treatment
View SamplesPreviously, we reported that the transcription factor Mesp1 promotes the cell fates of cardiomyocytes, smooth muscle, and vascular endothelium. Recently, hematopoietic stem cells (HSCs) were shown to derive from hemogenic endothelium. Since Mesp1 regulates development of endothelium, it potentially could influence gene expression related to hematopoietic development.
Dual actions of Meis1 inhibit erythroid progenitor development and sustain general hematopoietic cell proliferation.
Specimen part, Treatment
View Samples