(Phys.org) —Last month, researchers reported the creation of the first primitive brain-like structures made from human stem cells. To create the complex morphology of these cerebral organoids, cells within a proliferating neuroectodermal layer were converted into so-called radial glial precursors (RGPs), which then rough out the basic floor plan of the cerebrum. As seen in the image above, the migrating and replicating RPGs span the thickness of the telencephalon in a normally developing brain, and provide a scaffolding for later arriving cells to subsequently migrate on themselves. A new paper published in Cell describes how the division of RPGs is tightly controlled by the location of the nucleus as it is motored about between the poles of the extended cell. The authors expand upon earlier work detailing the precise cytoskeletal couplers which power these translocations in specific directions, and ultimately piece together how these motor proteins, specifically dynein, are harnessed by nuclear pore complexes. Once this motor-nuclear mating occurs, migration in the apical direction (in this context, apical is towards the ventricle and basal is towards the surface) is initiated followed by subsequent entry into mitosis.
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