Meeting Abstract
Regeneration is a developmental process that allows an organism to re-grow a lost body part. Historically, the most studied aspect of limb regeneration across Pancrustacea is its morphological basis and its dependence on successful molting. Although there are distinct morphological differences between Insect and Crustacean regeneration processes, in both cases the phenomenon is initiated via formation of a blastema, followed by proliferation, dedifferentiation, and redifferentiation of blastemal cells to generate a functional limb. In recent years, with the availability of sequence data and tools to manipulate gene expression, the emphasis of this field has shifted towards the genetic basis of limb regeneration. Among insects this focus is on genes that are known to be required during embryonic leg development. RNAi mediated functional studies conducted during regeneration of imaginal discs of Drosophila melanogaster, larval legs of Tribolium castaneum, and nymphal legs of Gryllus bimaculatus reveal that several conserved pathways and transcription factors (Dachshund, Distal-less, Decapentaplegic, Hedgehog) are required for successful leg regeneration. In contrast to insect limb regeneration studies, work by the crustacean biologists has focused on the hormonal basis of limb re-growth. Regeneration in decapods, like Uca pugilator and Gecarcinus lateralis, occurs in discrete growth phases in tandem with the molt cycle stages. Recent studies have shown that ecdysteroid hormone signaling is necessary for blastemal proliferation. Although the current research emphases of Insect and Crustacean limb regeneration are fairly distinct, the results generated by functional studies of a wide array of regeneration genes will be beneficial to the entire Pancrustacean scientific community for generating testable regeneration models.
