Article

Gene expression profile of the regeneration epithelium during axolotl limb regeneration

Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, USA.
Developmental Dynamics (Impact Factor: 2.67). 07/2011; 240(7):1826-40. DOI: 10.1002/dvdy.22669
Source: PubMed

ABSTRACT Urodele amphibians are unique among adult vertebrates in their ability to regenerate missing limbs. The process of limb regeneration requires several key tissues including a regeneration-competent wound epidermis called the regeneration epithelium (RE). We used microarray analysis to profile gene expression of the RE in the axolotl, a Mexican salamander. A list of 125 genes and expressed sequence tags (ESTs) showed a ≥1.5-fold expression in the RE than in a wound epidermis covering a lateral cuff wound. A subset of the RE ESTs and genes were further characterized for expression level changes over the time-course of regeneration. This study provides the first large scale identification of specific gene expression in the RE.

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    • "This suggests that these molecules are not limbspecific , although sustained expression in the limb WE may impose some necessary function to the WE during limb regeneration. Regardless, the fact that these genes seem to be unique to salamanders (Campbell et al., 2011) and show strong and specific expression in the WE warrants further functional studies. A surprising result was the observation that myelin-associated genes were up-regulated and both limb-specific and nervedependent . "
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