Similar Datasets
Project description:During development, the meninges act as a regulator of neocortical development by secreting ligands that act on neural cells to regulate neurogenesis and neuronal migration. Meninges-derived retinoic acid (RA) promotes neocortical progenitor cell cycle exit however the underlying mechanism is unknown. Here, we use Foxc1-mutant embryos that lack meninges-derived ligands, spatial transcriptomics, and profiling of retinoic-acid receptor-a (RARa) DNA binding to identify the neurogenic transcriptional mechanisms of RA signaling in cortical neural progenitors. We determined that meningeal-derived RA controls neurogenesis by suppressing self-renewal pathways Notch signaling and the transcription factor Sox2. We show that RARα binds in the Sox2ot promoter, a long non-coding RNA that regulates Sox2 expression, and RA promotes Sox2ot expression in neocortical progenitors. Our findings elucidate a previously unknown mechanism of howmeningeal RA coordinates neocortical development and insight into how defects in meningeal develop can cause neurodevelopmental disorders.
2024-09-25 | GSE269283 | GEO
Project description:During development, the meninges act as a regulator of neocortical development by secreting ligands that act on neural cells to regulate neurogenesis and neuronal migration. Meninges-derived retinoic acid (RA) promotes neocortical progenitor cell cycle exit however the underlying mechanism is unknown. Here, we use Foxc1-mutant embryos that lack meninges-derived ligands, spatial transcriptomics, and profiling of retinoic-acid receptor-a (RARa) DNA binding to identify the neurogenic transcriptional mechanisms of RA signaling in cortical neural progenitors. We determined that meningeal-derived RA controls neurogenesis by suppressing self-renewal pathways Notch signaling and the transcription factor Sox2. We show that RARα binds in the Sox2ot promoter, a long non-coding RNA that regulates Sox2 expression, and RA promotes Sox2ot expression in neocortical progenitors. Our findings elucidate a previously unknown mechanism of howmeningeal RA coordinates neocortical development and insight into how defects in meningeal develop can cause neurodevelopmental disorders.
2024-09-25 | GSE269282 | GEO
Project description:Meningeal-derived retinoic acid regulates neurogenesis via suppression of Notch and Sox2
| PRJNA1120892 | ENA
Project description:Meningeal-derived retinoic acid regulates neurogenesis via suppression of Notch and Sox2 [CUT&Run]
| PRJNA1120897 | ENA
Project description:Meningeal-derived retinoic acid regulates neurogenesis via suppression of Notch and Sox2 [Spatial Transcriptomics]
| PRJNA1120899 | ENA
Project description:Hematopoietic stem cells (HSCs) are multipotent progenitors that generate all vertebrate adult blood lineages. Recent analyses have highlighted the importance of somite-derived signaling factors in regulating HSC specification and emergence from dorsal aorta hemogenic endothelium. However, these factors remain largely uncharacterized. We provide evidence that the vitamin A derivative retinoic acid (RA) functions as an essential regulator of zebrafish HSC formation. Temporal analyses indicate that RA is required for HSC gene expression prior to dorsal aorta formation, at a time when the predominant RA synthesis enzyme, aldh1a2, is strongly expressed within the paraxial mesoderm and somites. Previous research implicated the Cxcl12 chemokine and Notch signaling pathways in HSC formation. Consequently, to understand how RA regulates HSC gene expression, we surveyed the expression of components of these pathways in RA-depleted zebrafish embryos. During somitogenesis, RA-depleted embryos exhibit altered expression of jam1a and jam2a, which potentiate Notch signaling within nascent endothelial cells. RA-depleted embryos also exhibit a severe reduction in the expression of cxcr4a, the predominant Cxcl12b receptor. Furthermore, pharmacological inhibitors of RA synthesis and Cxcr4 signaling act in concert to reduce HSC formation. Our analyses demonstrate that somite-derived RA functions to regulate components of the Notch and Cxcl12 chemokine signaling pathways during HSC formation.
| S-EPMC5115706 | biostudies-literature
Project description:Leptomeningeal metastasis is associated with dismal prognosis and has few treatment options. However, very little is known about the immune response to leptomeningeal metastasis. Here, by establishing an immunocompetent mouse model of breast cancer leptomeningeal metastasis, we found that tumor-specific CD8+ T cells were generated in deep cervical lymph nodes (dCLNs) and played an important role in controlling leptomeningeal metastasis. Mechanistically, T cells in dCLNs displayed a senescence phenotype and their recruitment was impaired in mice bearing cancer cells that preferentially colonized in leptomeningeal space. Upregulation of p53 suppressed the transcription of VLA-4 in senescent dCLN T cells and consequently inhibited their migration to the leptomeningeal compartment. Clinically, CD8+ T cells from the cerebrospinal fluid of patients with leptomeningeal metastasis exhibited senescence and VLA-4 downregulation. Collectively, our findings demonstrated that CD8+ T cell immunosenescence drives leptomeningeal metastasis.
| S-EPMC9803356 | biostudies-literature
Project description:The transcription factor SRY (sex-determining region)-box 2 (SOX2) is an important functional marker of neural precursor cells (NPCs) and plays a critical role in self-renewal and neuronal differentiation; however, the molecular mechanisms underlying its functions are poorly understood. Using human embryonic stem cell-derived NPCs to model neurogenesis, we found that SOX2 is required to maintain optimal levels of LIN28, a well-characterized suppressor of let-7 microRNA biogenesis. Exogenous LIN28 expression rescued the NPC proliferation deficit, as well as the early but not the late stages of the neurogenic deficit associated with the loss of SOX2. We found that SOX2 binds to a proximal site in the LIN28 promoter region and regulates LIN28 promoter acetylation, likely through interactions with the histone acetyltransferase complex. Misexpression of let-7 microRNAs in NPCs reduced proliferation and inhibited neuronal differentiation, phenocopying the loss of SOX2. In particular, we identified let-7i as a novel and potent inhibitor of neuronal differentiation that targets MASH1 and NGN1, two well-characterized proneural genes. In conclusion, we discovered the SOX2-LIN28/let-7 pathway as a unique molecular mechanism governing NPC proliferation and neurogenic potential.
| S-EPMC3740872 | biostudies-literature
Project description:Sox2 is known to be important for neuron formation, but the precise mechanism through which it activates a neurogenic program and how this differs from its well-established function in self-renewal of stem cells remain elusive. In this study, we identified a highly conserved cyclin-dependent kinase (Cdk) phosphorylation site on serine 39 (S39) in Sox2. In neural stem cells (NSCs), phosphorylation of S39 enhances the ability of Sox2 to negatively regulate neuronal differentiation, while loss of phosphorylation is necessary for chromatin retention of a truncated form of Sox2 generated during neurogenesis. We further demonstrated that nonphosphorylated cleaved Sox2 specifically induces the expression of proneural genes and promotes neurogenic commitment in vivo Our present study sheds light on how the level of Cdk kinase activity directly regulates Sox2 to tip the balance between self-renewal and differentiation in NSCs.
| S-EPMC5533875 | biostudies-literature
Project description:The mechanism of action of retinoic acid (RA) is of broad relevance to cell and developmental biology, nutrition, and cancer chemotherapy. RA is known to induce expression of the Burkitt's lymphoma receptor 1 (BLR1) gene which propels RA-induced cell cycle arrest and differentiation of HL-60 human myeloblastic leukemia cells, motivating the present analysis of transcriptional regulation of blr1 expression by RA. The RA-treated HL-60 cells used here expressed all RA receptor (RAR) and retinoid X receptor (RXR) subtypes (as detected by Northern analysis) except RXRgamma. Treatment with RAR- and RXR-selective ligands showed that RARalpha synergized with RXRalpha to transcriptionally activate blr1 expression. A 5'-flanking region capable of supporting RA-induced blr1 activation in HL-60 cells was found to contain a 205-bp sequence in the distal portion that was necessary for transcriptional activation by RA. Within this sequence DNase I footprinting revealed that RA induced binding of a nuclear protein complex to an element containing two GT boxes. Electromobility shift assays (EMSAs) and supershift assays showed that this element bound recombinant RARalpha and RXRalpha. Without RA there was neither complex binding nor transcriptional activation. Both GT boxes were needed for binding the complex, and mutation of either GT box caused the loss of transcriptional activation by RA. The ability of this cis-acting RAR-RXR binding element to activate transcription in response to RA also depended on downstream sequences where an octamer transcription factor 1 (Oct1) site and a nuclear factor of activated T cells (NFATc) site between this element and the transcriptional start, as well as a cyclic AMP response element binding factor (CREB) site between the transcriptional start and first exon of the blr1 gene, were necessary. Each of these sites bound its corresponding transcription factor. A transcription factor-transcription factor binding array analysis of nuclear lysate from RA-treated cells indicated several prominent RARalpha binding partners; among these, Oct1, NFATc3, and CREB2 were identified by competition EMSA and supershift and chromatin immunoprecipitation assays as components of the complex. RA upregulated expression of these three factors. In sum the results of the present study indicate that RA-induced expression of blr1 expression depends on a novel RA response element. This cis-acting element approximately 1 kb upstream of the transcriptional start consists of two GT boxes that bind RAR and RXR in a nuclear protein complex that also contains Oct1, NFATc3, and CREB2 bound to their cognate downstream consensus binding sites.
| S-EPMC355834 | biostudies-literature