TL;DR: The intervening migrations, particularly in the human nervous system, form the subject of this review and are suggested that the special relationships involved in these various migrations are probably mediated by cell surface properties, and that such surface properties will come to be defined through analysis of reaggregation tissue cultures, experimental and natural chimeras, and by immunological definition of antigens on CNS cells at different stages of development.
TL;DR: An hypothesis is presented which accounts for the extensive cell migrations during histogenesis as a means for attaining particular synaptic contacts.
TL;DR: It is reported that mice lacking Math1 fail to form granule cells and are born with a cerebellum that is devoid of an external germinal layer, the first gene to be shown to be required in vivo for the genesis of granules cells, and hence the predominant neuronal population in the cerebellums.
Abstract: The cerebellum is essential for fine motor control of movement and posture, and its dysfunction disrupts balance and impairs control of speech, limb and eye movements. The developing cerebellum consists mainly of three types of neuronal cells: granule cells in the external germinal layer, Purkinje cells, and neurons of the deep nuclei. The molecular mechanisms that underlie the specific determination and the differentiation of each of these neuronal subtypes are unknown. Math1, the mouse homologue of the Drosophila gene atonal, encodes a basic helix-loop-helix transcription factor that is specifically expressed in the precursors of the external germinal layer and their derivatives. Here we report that mice lacking Math1 fail to form granule cells and are born with a cerebellum that is devoid of an external germinal layer. To our knowledge, Math1 is the first gene to be shown to be required in vivo for the genesis of granule cells, and hence the predominant neuronal population in the cerebellum.
TL;DR: It is shown in human and mouse medulloblastoma that cells expressing the glia-associated markers Gfap and Olig2 are neoplastic and retain features of embryonic-type granule lineage progenitors, indicating that acquisition of CGNP identity is essential for tumorigenesis.
TL;DR: Human-ESC-derived cerebellar progenitors exhibit substantial self-organizing potential for generating a polarized structure reminiscent of the early human cerebellum at the first trimester.