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Erkol, E.

Publications and source records attributed to Erkol, E..

4 recordsLinked to original sources

Species-specific Rates of Fatty Acid MetabolismSet the Scale of Temporal Patterning of Corticogenesisthrough Protein Acetylation Dynamics

Developmental processes display temporal differences across species, leading to divergence in organ size and composition. In the cerebral cortex, neurons of diverse identities are generated sequentially through a temporal patterning mechanism conserved throughout mammals. This corticogenesis process is considerably prolonged in the human species, leading to increased brain size and complexity, but the underlying molecular mechanisms remain largely unknown. Here we found that human cortical progenitors displayed lower levels of fatty acid oxidation than their mouse counterparts, in line with their protracted pattern. Treatments that enhance mitochondrial fatty acid oxidation (FAO) accelerated the development of human cortical organoids, including faster progression of neural progenitor cell fate and precocious generation of late-born neurons and glia. FAO accelerated temporal patterning through increased Acetyl-CoA-dependent protein acetylation, including on specific histone transcriptional marks. Thus, species-specific metabolic rates regulate the turnover of post-translation modifications to set the scale of temporal gene regulatory networks of corticogenesis.

neuroscience↗

The microcephaly gene ASPM is required for the timely generation of human outer-radial glia progenitors by controlling mitotic spindle orientation

Abnormal spindle-like, microcephaly-associated (ASPM) is the most commonly mutated gene in primary microcephaly (MCPH), characterized by reduced brain size and intellectual deficiency. The mechanisms underlying MCPH have remained unclear, as ASPM disruption leads to distinct phenotypes depending on the species studied. Here, we studied the impact of ASPM pathogenic mutations on human corticogenesis in organoid models. We found that at earliest stages of neurogenesis, ASPM mutant cortical progenitors, located at the apical surface of the neuroepithelium, display transient mitotic spindle randomization. The mutant progenitors then delaminate basally to adopt precociously the characteristics of outer radial glia cells (oRGC), a population of progenitors selectively amplified in human corticogenesis. Subsequently, cortical progenitors are depleted through decreased amplification and increased apoptosis. Thus, ASPM regulates the timely generation of oRGC by controlling mitotic spindle orientation, shedding light on how species-specific features of neurogenesis may confer vulnerability to neurodevelopmental diseases.

neuroscience↗

Species-specific mitochondria dynamics and metabolism regulate the timing of neuronal development

The evolution of species involves changes in the timeline of key developmental programs. Among these, neuronal development is considerably prolonged in the human cerebral cortex compared with other mammals, leading to brain neoteny. Here we explore whether mitochondria influence the species-specific properties of cortical neuron maturation. By comparing human and mouse cortical neuronal maturation at high temporal and cell resolution, we found a slower pattern of mitochondria development in human cortical neurons compared with the mouse, together with lower mitochondria metabolic activity, particularly oxidative phosphorylation. Stimulation of mitochondria metabolism in human neurons resulted in accelerated maturation, leading to excitable and complex cells weeks ahead of time. Our data identify mitochondria as important regulators of the pace of neuronal development underlying human-specific features of brain evolution.

neuroscience↗

CROCCP2 acts as a human-specific modifier of cilia dynamics and mTOR signalling to promote expansion of cortical progenitors.

The primary cilum is a central component of signalling during neural development, from regional patterning to neuronal differentiation. Here we focus on CROCCP2, a hominid-specific gene duplicate from CROCC (Ciliary Rootlet Coiled Coil), also known as rootletin, that encodes the major protein component of the ciliary rootlet. We find that CROCCP2 is highly expressed in the human fetal brain and not in other primate species. CROCCP2 gain of function in the mouse embryonic cortex results in decreased ciliogenesis, increased mTOR signalling, and increased cell size of radial glial cells, leading to increased generation of intermediate/basal progenitors and increased neuronal output. CROCCP2 impacts cilia dynamics and neurogenesis by inhibition of the IFT20 ciliary trafficking protein. Our data identify a human-specific protein that drives cortical basal progenitor expansion through modulation of ciliary dynamics.

neuroscience↗