Selective Rab11 transport and the intrinsic regenerative ability of CNS axons
- University of Cambridge, United Kingdom
- University of Edinburgh, United Kingdom
- University of Leeds, United Kingdom
Abstract
Neurons lose intrinsic axon regenerative ability with maturation, but the mechanism remains unclear. Using an in-vitro laser axotomy model, we show a progressive decline in the ability of cut CNS axons to form a new growth cone and then elongate. Failure of regeneration was associated with increased retraction after axotomy. Transportation into axons becomes selective with maturation; we hypothesized that selective exclusion of molecules needed for growth may contribute to regeneration decline. With neuronal maturity Rab11 vesicles (which carry many molecules involved in axon growth) became selectively targeted to the somatodendritic compartment and excluded from axons. Their transport changed from bidirectional to retrograde. However, on overexpression Rab11 was mistrafficked into proximal axons, and these axons showed less retraction and enhanced regeneration after axotomy. These results suggest that the decline of intrinsic axon regenerative ability is associated with selective exclusion of key molecules, and that manipulation of transport can enhance regeneration.
Data availability
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Maturation of cortical neuronsPublicly available at NCBI Gene Expression Omnibus (accession no: GSE92856).
Article and author information
Author details
Funding
Medical Research Council (G1000864)
- James Fawcett
Christopher and Dana Reeve Foundation (International Consortium)
- James Fawcett
European Research Council (ECMneuro)
- James Fawcett
GlaxoSmithKline International Scholarship
- Hiroaki Koseki
Honjo International Scholarship Foundation
- Hiroaki Koseki
Bristol Myers Squibb Graduate Studentship
- Hiroaki Koseki
National Institute of Health Research (Cambridge Biomedical Research Centre)
- James Fawcett
Czech ministry of education (CZ.02.1.01/0.0./0.0/15_003/0000419)
- Jessica CF Kwok
- James Fawcett
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Koseki 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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