Lineage tracing of genome-edited alleles reveals high fidelity axolotl limb regeneration
Abstract
Salamanders are unparalleled among tetrapods in their ability to regenerate many structures, including entire limbs, and the study of this ability may provide insights into human regenerative therapies. The complex structure of the limb poses challenges to the investigation of the cellular and molecular basis of its regeneration. Using CRISPR/Cas, we genetically labelled unique cell lineages within the developing axolotl embryo and tracked the frequency of each lineage within amputated and fully regenerated limbs. This allowed us, for the first time, to assess the contributions of multiple low frequency cell lineages to the regenerating limb at once. Our comparisons reveal that regenerated limbs are high fidelity replicas of the originals even after repeated amputations.
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Author details
Funding
Connecticut Innovations (Seed Grant 15RMA-YALE-09)
- Grant Parker Flowers
Eunice Kennedy Shriver National Institute of Child Health and Human Development (Individual Postdoctoral Fellowship F32HD086942)
- Grant Parker Flowers
Connecticut Innovations (Established Investigator Award 15-RMB-YALE-01)
- Craig M Crews
National Institute of General Medical Sciences (Predoctoral Training Fellowship T32GM007499)
- Lucas D Sanor
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Experimental procedures were approved by the Yale University IACUC (2016-10557) and were in accordance with all federal policies and guidelines governing the use of vertebrate animals.
Copyright
© 2017, Flowers 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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