2013 Fiscal Year Final Research Report
Generation of Multiple Classes of V0 Neurons in Zebrafish Spinal Cord : Progenitor Heterogeneity and Temporal Control of Neuronal Diversity
Project/Area Number |
23700409
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Research Category |
Grant-in-Aid for Young Scientists (B)
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Allocation Type | Multi-year Fund |
Research Field |
Neuroscience in general
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Research Institution | 大学共同利用機関法人自然科学研究機構(岡崎共通研究施設) (2012-2013) National Institutes of Natural Sciences Okazaki Research Facilities (2011) |
Principal Investigator |
SATO Chie 大学共同利用機関法人自然科学研究機構(岡崎共通研究施設), 岡崎統合バイオサイエンスセンター, 特別協力研究員 (50583241)
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Project Period (FY) |
2011 – 2013
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Keywords | ゼブラフィッシュ / 神経前駆体 |
Research Abstract |
The developing spinal cord is subdivided into distinct progenitor domains, each of which gives rise to different types of neurons. However, the developmental mechanisms responsible for generating neuronal diversity within a domain are not well understood. Here, we have studied zebrafish V0 neurons, those that derive from the p0 progenitor domain, to address this question. We find that all V0 neurons have commissural axons, but they can be divided into excitatory and inhibitory classes. V0 excitatory neurons (V0-e) can be further categorized into three groups based on their axonal trajectories; V0-eA (ascending), V0-eB (bifurcating), and V0-eD (descending) neurons. By using time-lapse imaging of p0 progenitors and their progeny, we show that inhibitory and excitatory neurons are produced from different progenitors. We also demonstrate that V0-eA neurons are produced from distinct progenitors, while V0-eB and V0-eD neurons are produced from common progenitors. We then use birth-date analysis to reveal that V0-eA, V0-eB, and V0-eD neurons arise in this order. By perturbing Notch signaling and accelerating neuronal differentiation, we predictably alter the generation of early born V0-e neurons at the expense of later born ones. These results suggest that multiple types of V0 neurons are produced by two distinct mechanisms; from heterogeneous p0 progenitors and from the same p0 progenitor, but in a time-dependent manner.
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