Mutant Newts Can Regenerate Previously Defective Limbs

Many salamanders have the remarkable ability to regrow their own limbs and tails after an injury. How are they able to do this, while more complex mammals, such as humans, cannot?

“Certain animals like zebrafish and salamanders are able to regenerate body parts, but higher up on the evolutionary tree of life, regeneration happens much more rarely,” says Marianne Bronner, the Edward B. Lewis Professor of Biology and director of the Beckman Institute at Caltech. “Though we’ve seen that some human babies can actually regenerate the tips of their fingers, this ability does not persist through adulthood. We want to understand the molecular processes that underlie regeneration.”

Usually, the only time an animal grows a limb is during embryonic development, which has led researchers to theorize that the processes guiding development and regeneration are similar. However, a new collaborative study by the Bronner Lab at Caltech and the laboratory of Ken-ichi T. Suzuki of the National Institute for Basic Biology in Japan shows that a particular molecule necessary for proper development is not needed for regeneration.

A paper describing the research appears in the journal Proceedings of the National Academy of Sciences on March 5.

Read more on the TCCI for Neuroscience website