Differences and similarities between human and chimpanzee neural progenitors during cerebral cortex development
Abstract
Human neocortex expansion likely contributed to the remarkable cognitive abilities of humans. This expansion is thought to primarily reflect differences in proliferation versus differentiation of neural progenitors during cortical development. Here, we have searched for such differences by analysing cerebral organoids from human and chimpanzees using immunohistochemistry, live imaging, and single-cell transcriptomics. We find that the cytoarchitecture, cell type composition, and neurogenic gene expression programs of humans and chimpanzees are remarkably similar. Notably, however, live imaging of apical progenitor mitosis uncovered a lengthening of prometaphase-metaphase in humans compared to chimpanzees that is specific to proliferating progenitors and not observed in non-neural cells. Consistent with this, the small set of genes more highly expressed in human apical progenitors points to increased proliferative capacity, and the proportion of neurogenic basal progenitors is lower in humans. These subtle differences in cortical progenitors between humans and chimpanzees may have consequences for human neocortex evolution.
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Author details
Funding
Boehringer Ingelheim Fonds
- Sabina Kanton
Paul G. Allen Family Foundation
- Svante Pääbo
Deutsche Forschungsgemeinschaft (DFG, SFB 655, A2)
- Wieland B Huttner
European Research Council (ERC, 250197)
- Wieland B Huttner
DFG-Funded Center for Regenerative Therapies Dresden
- Wieland B Huttner
Fonds der Chemischen Industrie
- Wieland B Huttner
Max Planck Society
- Svante Pääbo
- Barbara Treutlein
- Wieland B Huttner
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Mice were kept pathogen-free at the Biomedical Services Facility of the MPI-CBG. All experiments using mice were performed according to the German Animal Welfare Legislation. In addition, research was approved by the Institutional Review Board of the Max Planck Institute of Molecular Cell Biology and Genetics.
Human subjects: Human fetal brain tissue (11-13 weeks post conception (wpc)) was obtained with informed written maternal consent followed by elective pregnancy termination. Research involving human tissue was approved by the Ethical Review Committee of the Universitaetsklinikum Carl Gustav Carus of the Technische Universitaet Dresden. In addition, research was approved by the Institutional Review Board of the Max Planck Institute of Molecular Cell Biology and Genetics.
Copyright
© 2016, Mora-Bermúdez et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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