Salamanders teach us how to regrow limbs

By Casey Frye, CCNN Writer

marbled salamander
Salamander cells can recognize when it’s time to replace a limb, and researchers can even trick these cells into growing extra limbs that aren’t necessary!

Losing a limb is a devastating experience suffered by one too many humans, but for salamanders, it’s no big deal. These slimy reptiles have the ability to regrow injured body parts like their hearts, spinal cords, brains, and lost limbs. For years, researchers have been studying these self-regenerating creatures to develop advanced treatments for humans, and they’ve recently made a groundbreaking discovery.

Our bodies grow by following instructions from a molecule known as DNA (deoxyribonucleic acid). The cells that make up the body continue to divide and multiply until they have completed these biological instructions. After that, the body works to maintain itself by replacing dead cells and repairing damage. When humans and other mammals lose an entire limb, there aren’t clear instructions on how to regrow it again, but with a little help from salamanders, that may not be true anymore.

Researchers were hard at work studying the processes that control a salamander’s impressive self-regeneration, when they uncovered a special molecular pathway – a group of molecules that work together to complete an activity. They called it the ERK pathway, and it’s basically a specific set of proteins that are constantly switched “on” and ready to grow body parts! What’s particularly fascinating is that humans also have this ERK pathway. However, it’s generally turned “off”. While the experimenters did try to activate the pathway in mammals, it wouldn’t stay on for more than 2 hours.

If scientists can find a technique that turns on those pathways for longer periods of time, it may mean the end of prosthetics (artificial limbs). Imagine how many war veterans could be healed with such an extraordinary medical breakthrough!

Featured image courtesy of Anita Gould on Flickr. Image of marbled salamander courtesy of cotinis on Flickr.