Notophthalmus viridescensSalamandridaeRegenerationExtremitiesTailAmbystoma mexicanumTriturusUrodelaAmbystomaPleurodelesLarvaLizardsAmputationPAX7 Transcription FactorLimb BudsNerve RegenerationHymecromoneLiver RegenerationAnimals, Genetically ModifiedXenopus ProteinsXenopus laevisSpinal CordPlanariansTurbellariaAnimal FinsGene Expression Regulation, DevelopmentalForelimbNotophthalmusBone RegenerationLimb SalvageLimb Deformities, Congenital