Transcriptomic landscape of the blastema niche in regenerating adult axolotl limbs at single-cell resolution

Nat Commun. 2018 Dec 4;9(1):5153. doi: 10.1038/s41467-018-07604-0.

Abstract

Regeneration of complex multi-tissue structures, such as limbs, requires the coordinated effort of multiple cell types. In axolotl limb regeneration, the wound epidermis and blastema have been extensively studied via histology, grafting, and bulk-tissue RNA-sequencing. However, defining the contributions of these tissues is hindered due to limited information regarding the molecular identity of the cell types in regenerating limbs. Here we report unbiased single-cell RNA-sequencing on over 25,000 cells from axolotl limbs and identify a plethora of cellular diversity within epidermal, mesenchymal, and hematopoietic lineages in homeostatic and regenerating limbs. We identify regeneration-induced genes, develop putative trajectories for blastema cell differentiation, and propose the molecular identity of fibroblast-like blastema progenitor cells. This work will enable application of molecular techniques to assess the contribution of these populations to limb regeneration. Overall, these data allow for establishment of a putative framework for adult axolotl limb regeneration.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Ambystoma mexicanum / genetics
  • Ambystoma mexicanum / physiology
  • Animal Experimentation
  • Animals
  • Cell Differentiation
  • Cell Lineage
  • Epidermal Cells
  • Epidermis / pathology
  • Epidermis / physiology
  • Extremities / embryology
  • Extremities / pathology
  • Extremities / physiology*
  • Fibroblasts / cytology
  • Fibroblasts / physiology
  • Gene Expression Profiling
  • Gene Expression Regulation, Developmental / genetics
  • Gene Expression Regulation, Developmental / physiology*
  • Immune System / physiology
  • In Situ Hybridization
  • Macrophages
  • Mesenchymal Stem Cells
  • Myeloid Cells / physiology
  • Nerve Regeneration / physiology
  • Neurons / physiology
  • Regeneration* / genetics
  • Sequence Analysis, RNA
  • Stem Cells / cytology
  • Stem Cells / physiology
  • Transcriptome*