Regeneration, the replacement of damaged or lost body parts, is a shared trait among some animal species – as any youngster who has cut an earthworm in half can attest to. But the repair of damaged tissue and organs in higher animals is also one of the primary goals of current stem cell research.
The common aquarium pet, zebrafish, is an excellent genetic model system, capable of regenerating its spinal cord, retina, heart and fins. A group of researchers writing in Genes & Development focused on fin regeneration, as it entails the coordination of a large number of different cells types to recreate the functional organ.
Their study reveals that microRNA depletion is a necessary step in tissue regeneration – a discovery with interesting implications for their use in regenerative medicine.