C05 - Glial checkpoints for neuronal circuitry recovery

https://rdp.sfb274.de/ (Research Data Platform) https://gepris.dfg.de/gepris/projekt/408885537 (DFG Gepris entry) The central nervous system (CNS) is a terminally differentiated tissue, where any insult carries a heightened risk - yet the tissue response to these insults is variable and can range from irreversible destruction to almost complete recovery. The rules that instruct these divergent outcomes are still unknown. The aim of this CRC is therefore to understand the biology of the multicellular ...

Astrocytes play key roles in brain function, but how these are orchestrated by transcription factors (TFs) in the adult brain and aligned with astrocyte heterogeneity is largely unknown. Here we examined the localization and function of the novel astrocyte TF Trps1 (Transcriptional Repressor GATA Binding 1) and the well-known astrocyte TF Sox9 by Cas9-mediated deletion using Mokola-pseudotyped lentiviral delivery into the adult cerebral cortex. Trps1 and Sox9 levels showed heterogeneity among ...

The glial environment influences neurological disease progression, yet much of our knowledge still relies on preclinical animal studies, especially regarding astrocyte heterogeneity. In murine models of traumatic brain injury, beneficial functions of proliferating reactive astrocytes on disease outcome have been unraveled, but little is known regarding if and when they are present in human brain pathology. Here we examined a broad spectrum of pathologies with and without intracerebral hemorrhage ...

Astrocytes are a viable source for generating new neurons via direct conversion. However, little is known about the neurogenic cascades triggered in astrocytes from different regions of the CNS. Here, we examine the transcriptome induced by the proneural factors Ascl1 and Neurog2 in spinal cord-derived astrocytes in vitro. Each factor initially elicits different neurogenic programs that later converge to a V2 interneuron-like state. Intriguingly, patch sequencing (patch-seq) shows no overall ...

Cell transplantation is a promising approach for the reconstruction of neuronal circuits after brain damage. Transplanted neurons integrate with remarkable specificity into circuitries of the mouse cerebral cortex affected by neuronal ablation. However, it remains unclear how neurons perform in a local environment undergoing reactive gliosis, inflammation, macrophage infiltration, and scar formation, as in traumatic brain injury (TBI). To elucidate this, we transplanted cells from the embryonic ...

Astrocyte heterogeneity has been well explored, but our understanding of white matter (WM) astrocytes and their distinctions from gray matter (GM) astrocytes remains limited. Here, we compared astrocytes from cortical GM and WM/corpus callosum (WM/CC) using single-cell RNA sequencing and spatial transcriptomics of the murine forebrain. The comparison revealed similarities but also significant differences between WM and GM astrocytes, including cytoskeletal and metabolic hallmarks specific to WM ...

Mitochondria account for essential cellular pathways, from ATP production to nucleotide metabolism, and their deficits lead to neurological disorders and contribute to the onset of age-related diseases. Direct neuronal reprogramming aims at replacing neurons lost in such conditions, but very little is known about the impact of mitochondrial dysfunction on the direct reprogramming of human cells. Here, we explore the effects of mitochondrial dysfunction on the neuronal reprogramming of induced ...

Direct neuronal reprogramming is a promising approach to regenerate neurons from local glial cells. However, mechanisms of epigenome remodeling and co-factors facilitating this process are unclear. In this study, we combined single-cell multiomics with genome-wide profiling of three-dimensional nuclear architecture and DNA methylation in mouse astrocyte-to-neuron reprogramming mediated by Neurogenin2 (Ngn2) and its phosphorylation-resistant form (PmutNgn2), respectively. We show that Ngn2 drives ...

Astrocytes play key roles in brain function but it is still poorly understood how these are orchestrated by pan-astrocyte transcriptions factors (TFs). Here we examined the function of the well-known pan-astrocyte TF Sox9 and the novel astrocyte TF Trps1 (Transcriptional Repressor GATA Binding 1) by Cas9-mediated in vivo deletion using Mokola-pseudotyped lentiviral delivery into the adult cerebral cortex. The consequences of deleting either Sox9 or Trps1 alone or simultaneously were explored at ...

Astrocyte-specific lentiviral constructs carrying gRNAs targeting Sox9, Trps1 and or both were injected in the cerebral cortex of adult transgenic mice expressing Cas9 protein. Transduced cells were retrived from the cortex 7 and 21 days post injection and subjected to SmartSeq2 for single cell sequencing

MACS-sorted astrocytes, obtained from postnatal mouse spinalc cord, were transduced in vitro with Ascl1 and Neurog2. Reprogrammed cells were analyzed by electrophysiology ar 3-to-4 weeks, and then single cells were collected and subjected to SmartSeq2 amplification

MACS-sorted astrocytes, obtained from postnatal mouse spinal cord, were transduced in vitro with Ascl1 and Neurog2. Reprogrammed cells were collected from the coverslips by suction and subjected to SmartSeq2 amplification

Purpose of the study is to compare the transcriptional profiles of astrocytes obtained from cortex gray matter and spinal cord of postnatal mice. Astrocytes were isolated from 2 regions via ACSA-2 sorting, cultured for 7 days and then subjected to RNA-seq

Spinal cord-derived astrocytes were transduced in cultures with retrovirus enconding a tamoxifen-dependent form of Ascl1 and Neurog2.Cells were treated for 24 hours, then transduced cells were FACS-sorted and their transcriptome analyzed.