Microarray and cDNA sequence analysis of transcription during nerve-dependent limb regeneration

This study investigates nerve-dependent limb regeneration in salamanders using microarray analysis and cDNA sequencing. Innervated and denervated forelimbs of Mexican axolotls were amputated, and transcripts were sampled at 0, 5, and 14 days of regeneration to understand the role of nerves in this process. The research revealed that many processes during early limb regeneration are nerve-independent. Genes crucial for wound healing were upregulated, while muscle-specific genes were downregulated in both innervated and denervated limbs during the early stages. The study identified new candidate gene sequences, which will greatly enable future studies of wound healing, epigenetics, genome stability, and nerve-dependent blastema formation and outgrowth using the axolotl model.

• 1
  Considerable similarity was observed between NR and DL transcriptional programs at 5 and 14 days post amputation (dpa).
• 2
  The majority of the transcriptional differences between NR and DL limbs were correlated with blastema formation; cell numbers increased in NR limbs after 5 dpa and this yielded distinct transcriptional signatures of cell proliferation in NR limbs at 14 dpa.
• 3
  Assembly of new 454 cDNA sequences with existing expressed sequence tag (EST) contigs from the Ambystoma EST database more than doubled (3935 to 9411) the number of non-redundant human-A. mexicanum orthologous sequences.