The freshwater crayfish is capable of regenerating limbs, following autotomy, injury and predation. In arthropod species, regeneration moulting are two processes linked strongly regulated by ecdysone. limbs divided into wound healing, blastema formation, cellular reprogramming tissue patterning. Limb cells undergo proliferation, dedifferentiation redifferentiation. A limb bud, containing folded...

In the cricket Gryllus bimaculatus, missing distal parts of the amputated leg are regenerated from the blastema, a population of dedifferentiated proliferating cells that forms at the distal tip of the leg stump. To identify molecules involved in blastema formation, comparative transcriptome analysis was performed between regenerating and normal unamputated legs. Components of JAK/STAT signalli...

Regeneration, the ability to replace lost tissues and body parts following traumatic injury, occurs widely throughout the animal tree of life. Regeneration occurs either by remodeling of pre-existing tissues, through addition of new cells by cell division, or a combination of both. We describe a staging system for posterior regeneration in the annelid, Capitella teleta, and use the C. teleta Ho...

One possible reason why regeneration remains enigmatic is that the dominant organisms used for studying regeneration are not amenable to genetic approaches. We mutagenized zebrafish and screened for temperature-sensitive defects in adult fin regeneration. The nightcap mutant showed a defect in fin regeneration that was first apparent at the onset of regenerative outgrowth. Positional cloning re...

Among vertebrates, urodele amphibians are the only tetrapods with the ability to regenerate complex structures such as limbs, tail, and spinal cord throughout their lives. Furthermore, the salamander regeneration process has been shown to reverse tumorigenicity. Fibroblasts are essential for salamander regeneration, but the mechanisms underlying their role in the formation of a regeneration bla...

Regeneration of the amphibian limb after amputation depends on division of blastemal cells, the progenitor cells of the regenerate. This division is controlled, at least in the early stages of regeneration, by the nerve supply to the blastema. A monoclonal antibody to newt blastema cells has provided evidence that Schwann cells and muscle fibers contribute to the blastema, and identifies blaste...

Axolotls (Ambystoma mexicanum) can completely regenerate lost limbs, whereas Xenopus laevis frogs cannot. During limb regeneration, a blastema is first formed at the amputation plane. It is thought that this regeneration blastema forms a limb by mechanisms similar to those of a developing embryonic limb bud. Furthermore, Xenopus laevis frogs can form a blastema after amputation; however, the bl...

While mammals have a limited capacity to repair bone defects, zebrafish can completely regenerate amputated bony structures of their fins. Fin regeneration is dependent on formation of a blastema, a progenitor cell pool accumulating at the amputation plane. It is unclear which cells the blastema is derived from, whether it forms by dedifferentiation of mature cells, and whether blastema cells a...

In mammals, the loss of a limb is irreversible. By contrast, urodele amphibians and teleost fish are capable of nearly perfect regeneration of lost appendages. This ability depends on direct interaction between the wound epithelium and mesenchymal progenitor cells of the blastema. It has been known for decades that contact between the wound epithelium and the underlying blastema is essential fo...