The Effects of Retinoids on Regenerating Axolotl Limbs
The limbs of amphibians normally regenerate only those parts distal to the amputation plane, an observation that has been formalized as the rule of distal transformation. The basis for this rule is the inheritance by the blastema of a cellular memory of its position of origin, termed positional value. Recently, vitamin A and its derivatives (retinoids) have been found to proximalize positional value, causing duplication of stump structures in the regenerate. Positional values along the proximodistal (PD) axis are associated with a gradient of cell surface adhesivity, and retinoids have been shown to alter adhesivity and glycoconjugate composition of cell surfaces in cultured avian and mammalian cells. These two observations suggest a potential approach to a cellular and molecular analysis of positional value in regenerating limbs.
University of Illinois - Urbana-Champaign
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University of Illinois at Urbana-Champaign