Stepwise wiring of the Drosophila olfactory map requires specific Plexin B levels
- Howard Hughes Medical Institute, Stanford University, United States
- Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, United States
Abstract
The precise assembly of a neural circuit involves many consecutive steps. The conflict between a limited number of wiring molecules and the complexity of the neural network impels each molecule to execute multiple functions at different steps. Here, we examined the cell-type specific distribution of endogenous levels of axon guidance receptor Plexin B (PlexB) in the developing antennal lobe, the first olfactory processing center in Drosophila. We found that different classes of olfactory receptor neurons (ORNs) express PlexB at different levels in two wiring steps - axonal trajectory choice and subsequent target selection. In line with its temporally distinct patterns, the proper levels of PlexB control both steps in succession. Genetic interactions further revealed that the effect of high-level PlexB is antagonized by its canonical partner Sema2b. Thus, PlexB plays a multifaceted role in instructing the assembly of the Drosophila olfactory circuit through temporally-regulated expression patterns and expression level-dependent effects.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
National Institutes of Health (R01-DC005982)
- Liqun Luo
Howard Hughes Medical Institute
- Liqun Luo
Stanford University (Vanessa Kong Kerzner Graduate Fellowship)
- Jiefu Li
Genentech Foundation (Genentech Foundation Predoctoral Fellowship)
- Jiefu Li
Stanford University (Stanford Neuroscience Institute Interdisciplinary Scholar)
- Hongjie Li
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Li 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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Stepwise wiring of the Drosophila olfactory map requires specific Plexin B levels
eLife 7:e39088.
https://doi.org/10.7554/eLife.39088
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