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bioRxiv · 10.1101/2022.04.04.487003

Tissue-wide Genetic and Cellular Landscape Shapes the Execution of Sequential PRC2 Functions in Neural Stem Cell Lineage Progression

Abstract

The generation of a correctly-sized cerebral cortex with all-embracing neuronal and glial cell-type diversity critically depends on faithful radial glial progenitor (RGP) cell proliferation/differentiation programs. Temporal RGP lineage progression is regulated by Polycomb Repressive Complex 2 (PRC2) and loss of PRC2 activity results in severe neurogenesis defects and microcephaly. How PRC2-dependent gene expression instructs RGP lineage progression is unknown. Here we utilize Mosaic Analysis with Double Markers (MADM)-based single cell technology and demonstrate that PRC2 is not cell-autonomously required in neurogenic RGPs but rather acts at the global tissue-wide level. Conversely, cortical astrocyte production and maturation is cell-autonomously controlled by PRC2-dependent transcriptional regulation. We thus reveal highly distinct and sequential PRC2 functions in RGP lineage progression that are dependent on complex interplays between intrinsic and tissue-wide properties. In a broader context our results imply a critical role for the genetic and cellular niche environment in neural stem cell behavior.

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Amberg, N., Pauler, F. M., Streicher, C., Hippenmeyer, S.. 2022-04-05. Tissue-wide Genetic and Cellular Landscape Shapes the Execution of Sequential PRC2 Functions in Neural Stem Cell Lineage Progression. https://doi.org/10.1101/2022.04.04.487003

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