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Biology subjects

Corsini, N. S.

Publications and source records attributed to Corsini, N. S..

4 recordsLinked to original sources

Cerebral organoids recapitulate interneuron chain migration in the human cortex

The human brain is incomplete at birth, with streams of late-born interneurons migrating into the postnatal cortex. This process is absent in rodents, limiting mechanistic investigation to post-mortem tissue. Here, we show that human cerebral organoids cultured for over six months recapitulate postnatal interneuron migration, enabling its mechanistic and genetic dissection. Live imaging and mathematical modeling revealed that interneurons intrinsically migrate in chains, while astrocyte interactions promote stream organization. Spatial and single-cell transcriptomics identified a distinct molecular signature of human postnatal migratory streams enriched for neurodevelopmental disorder-associated genes. Perturbation of the autism-associated genes CNTN5 and FGF14 differentially disrupted chain organization and migration. Thus, long-term cerebral organoids enable mechanistic analysis of previously inaccessible aspects of postnatal human brain development and their contributions to neurodevelopmental disease.

developmental biology↗

Morphogenesis and development of human telencephalic organoids in the absence and presence of exogenous ECM

Establishment and maintenance of apical-basal polarity is a fundamental step in brain development, instructing the organization of neural progenitor cells (NPCs) and the developing cerebral cortex. Particularly, basally located extracellular matrix (ECM) is crucial for this process. In vitro, epithelial polarization can be achieved via endogenous ECM production, or exogenous ECM supplementation. While neuroepithelial development is recapitulated in cerebral organoids, the effects of different ECM sources in tissue morphogenesis remain unexplored. Here, we show that exposure to exogenous ECM at early neuroepithelial stages causes rapid tissue polarization and complete rearrangement of neuroepithelial architecture within 3 days. In unexposed cultures, endogenous ECM production by NPCs results in gradual polarity acquisition over an extended time. After the onset of neurogenesis, tissue architecture and neuronal differentiation are largely independent of the initial ECM source. These results advance the knowledge on neuroepithelial biology in vitro, with a focus on mechanisms of exogenously- and endogenously-guided morphogenesis. They demonstrate the self-sustainability of neuroepithelial cultures by endogenous processes, prompting an urgent reassessment of indiscriminate use of exogenous ECM in these model systems.

developmental biology↗

Single-cell brain organoid screening identifies developmental defects in autism

Development of the human brain involves processes that are not seen in many other species, but can contribute to neurodevelopmental disorders (1-4). Cerebral organoids can be used to investigate neurodevelopmental disorders in a human context but are limited by variability and low throughput. We have developed the CRISPR-human organoids-scRNA-seq (CHOOSE) system that utilizes verified pairs of gRNAs, inducible CRISPR/Cas9-based genetic disruption, and single-cell transcriptomics for pooled loss-of-function screening in mosaic organoids. Genetic perturbations of 36 high-risk autism spectrum disorder (ASD) genes related to transcriptional regulation allowed us to identify their effects on cell fate determination and discover developmental stages susceptible to ASD gene perturbations. We construct a developmental gene regulatory network (GRN) of cerebral organoids from single-cell multiomic data including transcriptome and chromatin modalities and identify ASD-associated and perturbation-enriched regulatory modules. We show that perturbing members of the BAF chromatin remodeling complex leads to an expanded population of ventral telencephalon progenitors. Specifically, the BAF subunit ARID1B controls the fate transitions of progenitors to oligodendrocyte precursor cells and interneurons, which we confirmed in patient-specific induced pluripotent stem cell (iPSC) derived organoids. Our study paves the way for phenotypically characterizing disease susceptibility genes in human organoid models with cell type, developmental trajectory, and gene regulatory network readouts.

developmental biology↗

Cerebral organoid model reveals excessive proliferation of human caudal late interneuron progenitors in Tuberous Sclerosis Complex

Although the intricate and prolonged development of the human brain critically distinguishes it from other mammals1, our current understanding of neurodevelopmental diseases is largely based on work using animal models. Recent studies revealed that neural progenitors in the human brain are profoundly different from those found in rodent animal models2-5. Moreover, post-mortem studies revealed extensive migration of interneurons into the late-gestational and post-natal human prefrontal cortex that does not occur in rodents6. Here, we use cerebral organoids to show that overproduction of mid-gestational human interneurons causes Tuberous Sclerosis Complex (TSC), a severe neuro-developmental disorder associated with mutations in TSC1 and TSC2. We identify a previously uncharacterized population of caudal late interneuron progenitors, the CLIP-cells. In organoids derived from patients carrying heterozygous TSC2 mutations, dysregulation of mTOR signaling leads to CLIP-cell over-proliferation and formation of cortical tubers and subependymal tumors. Surprisingly, second-hit events resulting from copy-neutral loss-of-heterozygosity (cnLOH) are not causative for but occur during the progression of tumor lesions. Instead, EGFR signaling is required for tumor proliferation, opening up a promising approach to treat TSC lesions. Our study demonstrates that the analysis of developmental disorders in organoid models can lead to fundamental insights into human brain development and neuropsychiatric disorders.

neuroscience↗