Identification of Drosophila type II neuroblast lineages containing transit amplifying ganglion mother cells

Authors

  • Jason Q. Boone,

    1. Institute of Neuroscience and Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, Oregon 97403
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  • Chris Q. Doe

    Corresponding author
    1. Institute of Neuroscience and Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, Oregon 97403
    • Institute of Neuroscience and Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, Oregon 97403
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Abstract

Mammalian neural stem cells generate transit amplifying progenitors that expand the neuronal population, but these type of progenitors have not been studied in Drosophila. The Drosophila larval brain contains ∼100 neural stem cells (neuroblasts) per brain lobe, which are thought to bud off smaller ganglion mother cells (GMCs) that each produce two post-mitotic neurons. Here, we use molecular markers and clonal analysis to identify a novel neuroblast cell lineage containing “transit amplifying GMCs” (TA-GMCs). TA-GMCs differ from canonical GMCs in several ways: each TA-GMC has nuclear Deadpan, cytoplasmic Prospero, forms Prospero crescents at mitosis, and generates up to 10 neurons; canonical GMCs lack Deadpan, have nuclear Prospero, lack Prospero crescents at mitosis, and generate two neurons. We conclude that there are at least two types of neuroblast lineages: a Type I lineage where GMCs generate two neurons, and a type II lineage where TA-GMCs have longer lineages. Type II lineages allow more neurons to be produced faster than Type I lineages, which may be advantageous in a rapidly developing organism like Drosophila. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2008

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