An NMDA receptor-dependent mechanism for subcellular segregation of sensory inputs in the tadpole optic tectum

  1. Ali S Hamodi
  2. Zhenyu Liu
  3. Kara G Pratt  Is a corresponding author
  1. University of Wyoming, United States
  2. University of Wyomin, United States

Abstract

In the vertebrate CNS, afferent sensory inputs are targeted to specific depths or layers of their target neuropil. This patterning exists ab initio, from the very beginning, and therefore has been considered an activity-independent process. However, here we report that, during circuit development, the subcellular segregation of the visual and mechanosensory inputs to specific regions of tectal neuron dendrites in the tadpole optic tectum requires NMDA receptor activity. Blocking NMDARs during the formation of these sensory circuits, or removing the visual set of inputs, leads to less defined segregation, and suggests a correlation-based mechanism in which correlated inputs wire to common regions of dendrites. This can account for how two sets of inputs form synapses onto different regions of the same dendrite. Blocking NMDA receptors during later stages of circuit development did not disrupt segregation, indicating a critical period for activity-dependent shaping of patterns of innervation.

Article and author information

Author details

  1. Ali S Hamodi

    Department of Zoology and Physiology, University of Wyoming, Laramie, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Zhenyu Liu

    Department of Zoology and Physiology, University of Wyomin, Laramie, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Kara G Pratt

    Department of Zoology and Physiology, University of Wyoming, Laramie, United States
    For correspondence
    Kpratt4@uwyo.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6743-4757

Funding

Office of Experimental Program to Stimulate Competitive Research ((Outside the Box) Grant number 4201-11951-1001498 G)

  • Zhenyu Liu
  • Kara G Pratt

National Institute of General Medical Sciences (P30-GM-32128)

  • Ali S Hamodi
  • Zhenyu Liu
  • Kara G Pratt

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All experimental protocols have been approved by the University of Wyoming's Institutional Animal Care and Use Committee (IACUC). The protocol (# 20140411KP00089-03) was approved 04/11/16 to 04/10/17.

Reviewing Editor

  1. Ronald L Calabrese, Emory University, United States

Publication history

  1. Received: August 9, 2016
  2. Accepted: November 22, 2016
  3. Accepted Manuscript published: November 23, 2016 (version 1)
  4. Version of Record published: December 2, 2016 (version 2)

Copyright

© 2016, Hamodi 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. Ali S Hamodi
  2. Zhenyu Liu
  3. Kara G Pratt
(2016)
An NMDA receptor-dependent mechanism for subcellular segregation of sensory inputs in the tadpole optic tectum
eLife 5:e20502.
https://doi.org/10.7554/eLife.20502
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