axolotls tagged posts

Biologists have long been fascinated by the ability of salamanders to regrow entire limbs. Now Harvard researchers have solved part of the mystery of how they accomplish this feat—by activating stem cells throughout the body, not just at the injury site.

In a paper published in the journal Cell, researchers documented how this body-wide response in axolotl salamanders is triggered by the sympathetic nervous system—the iconic “fight or flight” network. The study raises the possibility that these mechanisms might one day be manipulated to regenerate human limbs and organs.

“We’ve shown the importance of the adrenaline stress signaling hormone in getting cells ready for regeneration,” said Duygu Payzin-Dogru, lead author of the new study and a postdo...

Keratinocytes produce collagen fibers, while deeper fibroblasts later modify the collagen fibers initially formed by keratinocytes. Challenging the long-standing belief that fibroblasts produce skin collagen, researchers at Okayama University have investigated collagen formation in the ‘glass-skinned’ amphibian axolotl and other vertebrates. They discovered that keratinocytes, the surface cells of the skin, are responsible for producing collagen, which is then transferred deeper to form the dermis. Later, fibroblasts migrate into this collagen layer, modifying and reinforcing its structure.

The skin consists of two primary layers...