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Human iPSC-derived cerebral organoids reveal progenitor pathology in EML1-linked cortical malformation

ABSTRACT: We report the single-cell RNA sequencing of day 33±2 human iPSC derived cerebral organoids harboring a CRIPSR/CAS9 mediated, heterozygous knock-out of the gene EML1 or the respective isogenic control organoids. By microdissection of several ventricular zones per organoid from 3 different batches followed by dissociation into single cells we obtained transcriptomic data of several thousand cells and we were able to identify different cell populations including RG cells (RG1), RG cells transitioning to bRG cells (RG to bRG), RG cells transitioning to neurons (RG2), intermediate progenitors and young neurons based on known marker genes (Nowakowski et al., 2017; Fan et al., 2020; Velasco et al., 2019; Pollen et al., 2015; Liu et al., 2017). When comparing the cell type composition between EML1-heKO and isogenic control-derived organoids we found a clear decrease of RG1 cells and a striking increase in the abundance of RG to bRG cells in the EML1-heKO condition, while only minor variations in the other cell clusters were observed. We further investigated molecular characteristics of the EML1-heKO derived RG to bRG cluster compared to control. Here we found a set of differentially expressed genes in the EML1-heKO compared to control. When further investigating these genes, we identified a clear upregulation of ECM and bRG markers Our data suggest that the RG to bRG cell cluster in the EML1-heKO is composed of a rather perturbed progenitor population not found as such in control organoids and most likely not reflecting a cell population present during normal human brain development.

ORGANISM(S): Homo sapiens

PROVIDER: GSE195666 | GEO | 2022/01/31

REPOSITORIES: GEO

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Human iPSC-derived cerebral organoids reveal progenitor pathology in EML1-linked cortical malformation

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