Abstract

Hippocampome.org is a comprehensive knowledge base of neuron types in the rodent hippocampal formation (dentate gyrus, CA3, CA2, CA1, subiculum, and entorhinal cortex). Although the hippocampal literature is remarkably information-rich, neuron properties are often reported with incompletely defined and notoriously inconsistent terminology, creating a formidable challenge for data integration. Our extensive literature mining and data reconciliation identified 122 neuron types based on neurotransmitter, axonal and dendritic patterns, synaptic specificity, electrophysiology, and molecular biomarkers. All ~3700 annotated properties are individually supported by specific evidence (~14,000 pieces) in peer-reviewed publications. Systematic analysis of this unprecedented amount of machine-readable information reveals novel correlations among neuron types and properties, the potential connectivity of the full hippocampal circuitry, and outstanding knowledge gaps. User-friendly browsing and online querying of Hippocampome.org may aid design and interpretation of both experiments and simulations. This powerful, simple, and extensible neuron classification endeavor is unique in its detail, utility, and completeness.

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Author details

  1. Diek W Wheeler

    Krasnow Institute for Advanced Study, George Mason University, Fairfax, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Charise M White

    Krasnow Institute for Advanced Study, George Mason University, Fairfax, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Christopher L Rees

    Krasnow Institute for Advanced Study, George Mason University, Fairfax, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Alexander O Komendantov

    Krasnow Institute for Advanced Study, George Mason University, Fairfax, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. David J Hamilton

    Krasnow Institute for Advanced Study, George Mason University, Fairfax, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Giorgio A Ascoli

    Krasnow Institute for Advanced Study, George Mason University, Fairfax, United States
    For correspondence
    ascoli@gmu.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Wheeler et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Diek W Wheeler
  2. Charise M White
  3. Christopher L Rees
  4. Alexander O Komendantov
  5. David J Hamilton
  6. Giorgio A Ascoli
(2015)
Hippocampome.org: A knowledge base of neuron types in the rodent hippocampus
eLife 4:e09960.
https://doi.org/10.7554/eLife.09960

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https://doi.org/10.7554/eLife.09960

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