Optical control of ERK and AKT signaling promotes axon regeneration and functional recovery of PNS and CNS in Drosophila
- University of Pennsylvania, United States
- University of Illinois at Urbana-Champaign, United States
Abstract
Neuroregeneration is a dynamic process synergizing the functional outcomes of multiple signaling circuits. Channelrhodopsin-based optogenetics shows the feasibility of stimulating neural repair but does not pin down specific signaling cascades. Here, we utilized optogenetic systems, optoRaf and optoAKT, to delineate the contribution of the ERK and AKT signaling pathways to neuroregeneration in live Drosophila larvae. We showed that optoRaf or optoAKT activation not only enhanced axon regeneration in both regeneration-competent and -incompetent sensory neurons in the peripheral nervous system but also allowed temporal tuning and proper guidance of axon regrowth. Furthermore, optoRaf and optoAKT differ in their signaling kinetics during regeneration, showing a gated versus graded response, respectively. Importantly in the central nervous system, their activation promotes axon regrowth and functional recovery of the thermonociceptive behavior. We conclude that non-neuronal optogenetics target damaged neurons and signaling subcircuits, providing a novel strategy in the intervention of neural damage with improved precision.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Vishnu V Krishnamurthy
Funding
National Institute of General Medical Sciences (R01GM132438)
- Huaxun Fan
- Savanna S Skeeters
- Vishnu V Krishnamurthy
- Kai Zhang
National Institute of Neurological Disorders and Stroke (1R01NS107392)
- Qin Wang
- Feng Li
- Yuanquan Song
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The experimental procedures have been approved by the Institutional Biosafety Committee (IBC) at the Children's Hospital of Philadelphia.
Copyright
© 2020, Wang 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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Optical control of ERK and AKT signaling promotes axon regeneration and functional recovery of PNS and CNS in Drosophila
eLife 9:e57395.
https://doi.org/10.7554/eLife.57395
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