Oxygen sensing helps explain why amphibians regenerate limbs but mammals cannot

Some animals can regrow lost body parts. Salamanders and frog tadpoles can rebuild entire limbs after amputation. Mammals cannot. For decades, biologists have tried to understand why. Now a team led by Can Aztekin at EPFL (now at the Friedrich Miescher Laboratory of the Max Planck Society) has discovered that oxygen plays a crucial role in limb regeneration. By comparing amputated limbs from frog tadpoles and embryonic mice, the researchers found that the way cells sense oxygen determines whether regeneration can even begin. The study is published in Science.