Tails with Lessons

Somewhere between axolotls able to regenerate their lost limbs, and humans who… can’t, lizards sit at an interesting place on the evolutionary tree. Like axolotls they can regenerate their tails – but not quite as completely. Now scientists use stem cells to give this regenerated gecko’s tail (pictured on the left) tissue ‘patterning’ matching its lost appendage. And key to achieving this is allowing the stem cells’ potential to thrive in the adult lizard. The team implant neural stem cells (NSCs) from an embryo into an adult’s tail stump, after editing genes to make the cells ignore pattern-blocking signals in the adult tissue. The gecko’s new tail grows from a ball-like blastema (right) with patterns of muscle (highlighted in white), cartilage (red) and dividing cells (green) around an unseen skeleton and nervous system. Researchers hope similar approaches may help human stem cells to treat hard-to-heal injuries, sharing lessons down the evolutionary tree.

Written by John Ankers

John Ankers

Writer

A former researcher in systems biology, John is now an online biology tutor and professional coach supporting the wellbeing of scientists and NHS professionals. He's writing, too, of course.

Website

• Images from the Lozito Lab, USC
• Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA, USA
• Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)
• Research published Nature Communications, October 2021