Frightened lizards can famously shed their tails to avoid capture, then re-grow them, apparently unharmed by the experience. In contrast, for us humans, repairing tissues in adult life is a slow and limited process, and lost limbs can only be replaced by artificial means. To understand how lizards are able to regenerate entire sets of organs, while most other vertebrates cannot, scientists investigated tail re-growth in the green anole lizard (pictured). They observed a change in the distribution of small sequences of nucleotides, known as micro-RNAs, in the lizards’ tails as they grew. Known to be important in development, and previously implicated in regeneration in amphibians, micro-RNAs can regulate the activity of multiple genes, coordinating the complex processes required to make sophisticated structures like limbs. Understanding how these micro-RNAs operate in lizards could one day inspire regenerative therapies, hoping to stimulate the regrowth of damaged tissues in humans too.
Written by Emmanuelle Briolat
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