Drosophila Fezf coordinates laminar-specific connectivity through cell-intrinsic and cell-extrinsic mechanisms
Abstract
Laminar arrangement of neural connections is a fundamental feature of neural circuit organization. Identifying mechanisms that coordinate neural connections within correct layers is thus vital for understanding how neural circuits are assembled. In the medulla of the Drosophila visual system neurons form connections within ten parallel layers. The M3 layer receives input from two neuron types that sequentially innervate M3 during development. Here we show that M3-specific innervation by both neurons is coordinated by Drosophila Fezf (dFezf), a conserved transcription factor that is selectively expressed by the earlier targeting input neuron. In this cell, dFezf instructs layer specificity and activates the expression of a secreted molecule (Netrin) that regulates the layer specificity of the other input neuron. We propose that employment of transcriptional modules that cell-intrinsically target neurons to specific layers, and cell-extrinsically recruit other neurons is a general mechanism for building layered networks of neural connections.
Article and author information
Author details
Funding
Lefler Center for the Study of Neurological Disorders
- Matthew Y Pecot
McKnight Foundation
- Matthew Y Pecot
Howard Hughes Medical Institute (Gilliam Fellowship for Advanced Study)
- Ivan J Santiago
Lefler Center for the Study of Neurological Disorders
- Jing Peng
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Liqun Luo, Howard Hughes Medical Institute, Stanford University, United States
Publication history
- Received: November 30, 2017
- Accepted: March 6, 2018
- Accepted Manuscript published: March 7, 2018 (version 1)
- Version of Record published: March 15, 2018 (version 2)
Copyright
© 2018, Peng 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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