Neurogenesis in the adult hippocampus contributes to learning and memory in the healthy brain but is dysregulated in metabolic and neurodegenerative diseases. The molecular relationships between neural stem cell activity, adult neurogenesis, and global metabolism are largely unknown. Here we applied unbiased systems genetics methods to quantify genetic covariation among adult neurogenesis and metabolic phenotypes in peripheral tissues of a genetically diverse family of rat strains, derived from a cross between the spontaneously hypertensive (SHR/OlaIpcv) strain and Brown Norway (BN-Lx/Cub). The HXB/BXH family is a very well established model to dissect genetic variants that modulate metabolic and cardiovascular diseases and we have accumulated deep phenome and transcriptome data in a FAIR-compliant resource for systematic and integrative analyses. Here we measured rates of precursor cell proliferation, survival of new neurons, and gene expression in the hippocampus of the entire HXB/BXH family, including both parents. These data were combined with published metabolic phenotypes to detect a neurometabolic quantitative trait locus (QTL) for serum glucose and neuronal survival on Chromosome 16: 62.1-66.3 Mb. We subsequently fine-mapped the key phenotype to a locus that includes the Telo2-interacting protein 2 gene (Tti2)-a chaperone that modulates the activity and stability of PIKK kinases. To verify the hypothesis that differences in neurogenesis and glucose levels are caused by a polymorphism in Tti2, we generated a targeted frameshift mutation on the SHR/OlaIpcv background. Heterozygous SHR-Tti2+/- mutants had lower rates of hippocampal neurogenesis and hallmarks of dysglycemia compared to wild-type littermates. Our findings highlight Tti2 as a causal genetic link between glucose metabolism and structural brain plasticity. In humans, more than 800 genomic variants are linked to TTI2 expression, seven of which have associations to protein and blood stem cell factor concentrations, blood pressure and frontotemporal dementia.
- MeSH
- fenotyp MeSH
- glukosa * genetika metabolismus MeSH
- hipokampus metabolismus MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- neurogeneze * genetika MeSH
- potkani inbrední BN MeSH
- potkani inbrední SHR MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
We review the molecular basis of several transcription factors (Eya1, Sox2), including the three related genes coding basic helix-loop-helix (bHLH; see abbreviations) proteins (Neurog1, Neurod1, Atoh1) during the development of spiral ganglia, cochlear nuclei, and cochlear hair cells. Neuronal development requires Neurog1, followed by its downstream target Neurod1, to cross-regulate Atoh1 expression. In contrast, hair cells and cochlear nuclei critically depend on Atoh1 and require Neurod1 expression for interactions with Atoh1. Upregulation of Atoh1 following Neurod1 loss changes some vestibular neurons' fate into "hair cells", highlighting the significant interplay between the bHLH genes. Further work showed that replacing Atoh1 by Neurog1 rescues some hair cells from complete absence observed in Atoh1 null mutants, suggesting that bHLH genes can partially replace one another. The inhibition of Atoh1 by Neurod1 is essential for proper neuronal cell fate, and in the absence of Neurod1, Atoh1 is upregulated, resulting in the formation of "intraganglionic" HCs. Additional genes, such as Eya1/Six1, Sox2, Pax2, Gata3, Fgfr2b, Foxg1, and Lmx1a/b, play a role in the auditory system. Finally, both Lmx1a and Lmx1b genes are essential for the cochlear organ of Corti, spiral ganglion neuron, and cochlear nuclei formation. We integrate the mammalian auditory system development to provide comprehensive insights beyond the limited perception driven by singular investigations of cochlear neurons, cochlear hair cells, and cochlear nuclei. A detailed analysis of gene expression is needed to understand better how upstream regulators facilitate gene interactions and mammalian auditory system development.
- MeSH
- kochlea cytologie metabolismus MeSH
- lidé MeSH
- neurogeneze genetika fyziologie MeSH
- transkripční faktory bHLH genetika metabolismus MeSH
- transkripční faktory genetika metabolismus MeSH
- vláskové buňky metabolismus MeSH
- vývojová regulace genové exprese MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Throughout development, neuronal progenitors undergo complex transformation into polarized nerve cells, warranting the directional flow of information in the neural grid. The majority of neuronal polarization studies have been carried out on rodent-derived precursor cells, programmed to develop into neurons. Unlike rodent neuronal cells, SH-SY5Y cells derived from human bone marrow present a sub-clone of neuroblastoma line, with their transformation into neuron-like cells showing a range of highly instructive neurobiological characteristics. We applied two-step retinoic acid (RA) and brain-derived neurotrophic factor (BDNF) protocol to monitor the conversion of undifferentiated SH-SY5Y into neuron-like cells with distinctly polarized axon-dendritic morphology and formation of bona fide synaptic connections. We show that BDNF is a key driver and regulator of the expression of axonal marker tau and dendritic microtubule-associated protein-2 (MAP2), with their sorting to distinct cellular compartments. Using selective kinase inhibitors downregulating BDNF-TrkB signaling, we demonstrate that constitutive activation of TrkB receptor is essential for the maintenance of established polarization morphology. Importantly, the proximity ligation assay applied in our preparation demonstrates that differentiating neuron-like cells develop elaborate synaptic connections enriched with hallmark pre- and postsynaptic proteins. Described herein findings highlight several fundamental processes related to neuronal polarization and synaptogenesis in human-derived cells, which are of major relevance to neurobiology and translational neuroscience.
- MeSH
- biologické markery MeSH
- buněčná diferenciace genetika MeSH
- lidé MeSH
- mozkový neurotrofický faktor genetika metabolismus MeSH
- nádorové buněčné linie MeSH
- neuroblastom genetika metabolismus patologie MeSH
- neurogeneze genetika MeSH
- neurony cytologie metabolismus MeSH
- reaktivní formy kyslíku MeSH
- signální transdukce MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
De novo heterozygous missense variants in the γ-tubulin gene TUBG1 have been linked to human malformations of cortical development associated with intellectual disability and epilepsy. Here, we investigated through in-utero electroporation and in-vivo studies, how four of these variants affect cortical development. We show that TUBG1 mutants affect neuronal positioning, disrupting the locomotion of new-born neurons but without affecting progenitors' proliferation. We further demonstrate that pathogenic TUBG1 variants are linked to reduced microtubule dynamics but without major structural nor functional centrosome defects in subject-derived fibroblasts. Additionally, we developed a knock-in Tubg1Y92C/+ mouse model and assessed consequences of the mutation. Although centrosomal positioning in bipolar neurons is correct, they fail to initiate locomotion. Furthermore, Tubg1Y92C/+ animals show neuroanatomical and behavioral defects and increased epileptic cortical activity. We show that Tubg1Y92C/+ mice partially mimic the human phenotype and therefore represent a relevant model for further investigations of the physiopathology of cortical malformations.
- MeSH
- centrozom metabolismus MeSH
- chování zvířat MeSH
- elektronová mikroskopie MeSH
- embryo savčí MeSH
- epilepsie genetika MeSH
- fibroblasty cytologie metabolismus ultrastruktura MeSH
- genetická predispozice k nemoci MeSH
- genový knockin MeSH
- HeLa buňky MeSH
- intravitální mikroskopie MeSH
- konfokální mikroskopie MeSH
- lidé MeSH
- malformace mozkové kůry genetika MeSH
- mikrotubuly genetika metabolismus MeSH
- missense mutace MeSH
- modely nemocí na zvířatech MeSH
- mozková kůra abnormality cytologie diagnostické zobrazování MeSH
- myši transgenní MeSH
- myši MeSH
- neurogeneze genetika MeSH
- neurony fyziologie MeSH
- pohyb buněk genetika MeSH
- tubulin genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
- práce podpořená grantem MeSH
Midbrain dopaminergic (mDA) neuron development has been an intense area of research during recent years. This is due in part to a growing interest in regenerative medicine and the hope that treatment for diseases affecting mDA neurons, such as Parkinson's disease (PD), might be facilitated by a better understanding of how these neurons are specified, differentiated and maintained in vivo. This knowledge might help to instruct efforts to generate mDA neurons in vitro, which holds promise not only for cell replacement therapy, but also for disease modeling and drug discovery. In this Primer, we will focus on recent developments in understanding the molecular mechanisms that regulate the development of mDA neurons in vivo, and how they have been used to generate human mDA neurons in vitro from pluripotent stem cells or from somatic cells via direct reprogramming. Current challenges and future avenues in the development of a regenerative medicine for PD will be identified and discussed.
- MeSH
- biologické modely MeSH
- dopaminergní neurony cytologie metabolismus MeSH
- lidé MeSH
- mezencefalon cytologie MeSH
- neurogeneze * genetika MeSH
- rozvržení tělního plánu genetika MeSH
- vývojová regulace genové exprese MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Sox3/SOX3 gene is considered to be one of the earliest neural markers in vertebrates. Despite the mounting evidence that Sox3/SOX3 is one of the key players in the development of the nervous system, limited data are available regarding the transcriptional regulation of its expression. This review is focused on the retinoic acid induced regulation of SOX3 gene expression, with particular emphasis on the involvement of retinoid receptors. Experiments with human embryonal carcinoma cells identified two response elements involved in retinoic acid/retinoid X receptor-dependent activation of the SOX3 gene expression: distal atypical retinoic acid-response element, consisting of two unique G-rich boxes separated by 49 bp, and proximal element comprising DR-3-like motif, composed of two imperfect hexameric half-sites. Importantly, the retinoic acid-induced SOX3 gene expression could be significantly down-regulated by a synthetic antagonist of retinoid receptors. This cell model provides a solid base for further studies on mechanism(s) underlying regulation of expression of SOX3 gene, which could improve the understanding of molecular signals that induce neurogenesis in the stem/progenitor cells both during development and in adulthood.
- MeSH
- buněčná diferenciace genetika účinky léků MeSH
- financování organizované MeSH
- genetické techniky využití MeSH
- kmenové buňky embryonálního karcinomu MeSH
- lidé MeSH
- metaanalýza jako téma MeSH
- modely genetické MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- neurogeneze genetika účinky léků MeSH
- receptory kyseliny retinové genetika MeSH
- regulace genové exprese fyziologie genetika účinky léků MeSH
- transkripční faktory SOXB1 genetika MeSH
- tretinoin MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- Publikační typ
- přehledy MeSH
Sonic hedgehog (Shh) and Wnt-7a are morphogens involved in embryonic as well as ongoing adult neurogenesis. Their effects on the differentiation and membrane properties of neonatal neural stem/progenitor cells (NS/PCs) were studied in vitro using NS/PCs transduced with either Shh or Wnt-7a. Eight days after the onset of in vitro differentiation the cells were analyzed for the expression of neuronal and glial markers using immunocytochemical and Western blot analysis, and their membrane properties were characterized using the patch-clamp technique. Our results showed that both Shh and Wnt-7a increased the numbers of cells expressing neuronal markers; however, quantitative immunocytochemical analysis showed that only Wnt-7a enhanced the outgrowth and the development of processes in these cells. In addition, Wnt-7a markedly suppressed gliogenesis. The electrophysiological analysis revealed that Wnt-7a increased, while Shh decreased the incidence of cells displaying a neuron-like current pattern, represented by outwardly rectifying K(+) currents and tetrodotoxin-sensitive Na(+) currents. Additionally, Wnt-7a increased cell proliferation only at the early stages of differentiation, while Shh promoted proliferation within the entire course of differentiation. Thus we can conclude that Shh and Wnt-7a interfere differently with the process of neuronal differentiation and that they promote distinct stages of neuronal differentiation in neonatal NS/PCs.
- MeSH
- buněčná diferenciace genetika MeSH
- kmenové buňky cytologie metabolismus MeSH
- kultivované buňky MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nervové kmenové buňky cytologie metabolismus MeSH
- neurogeneze genetika MeSH
- novorozená zvířata MeSH
- proteiny hedgehog genetika fyziologie MeSH
- proteiny Wnt genetika fyziologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- MeSH
- Alzheimerova nemoc etiologie terapie MeSH
- amyotrofická laterální skleróza etiologie terapie MeSH
- centrální nervový systém cytologie imunologie MeSH
- cévní mozková příhoda etiologie terapie MeSH
- hipokampus anatomie a histologie cytologie MeSH
- Huntingtonova nemoc etiologie terapie MeSH
- kmenové buňky * cytologie klasifikace MeSH
- lidé MeSH
- nervová tkáň * cytologie fyziologie imunologie MeSH
- neurodegenerativní nemoci etiologie genetika MeSH
- neurogeneze * fyziologie genetika imunologie MeSH
- neuroplasticita fyziologie genetika imunologie MeSH
- Parkinsonova nemoc etiologie terapie MeSH
- poranění míchy diagnóza etiologie rehabilitace MeSH
- reprodukční techniky využití MeSH
- roztroušená skleróza etiologie terapie MeSH
- transdiferenciace buněk fyziologie genetika imunologie MeSH
- Check Tag
- lidé MeSH
