A single gene can go a long way.

Scientists have discovered that by shutting down a single gene, latent regenerative abilities may be activated. For some animals, this could mean a new tail, internal organ, or even a brain.

While similar abilities are prevalent throughout all of nature, those examined in the new study are of particular interest, as they do not appear to occur naturally. Instead, these abilities are latent, and are only activated through genetic intervention.

"This is a fantastic advert for our field," biologist Aziz Aboobaker told Nature. "Here's a scenario where these animals don't regenerate a brain, and then by knocking out just one gene, it's possible to rescue that."

Research leading up to the discovery looked at the Wnt gene family - a group that codes for a series of enzymes carrying information from outside the cell to its nucleus. The gene family, which is found in all animals, is also responsible for producing a type of protein that controls gene expression.

Jochen Rink, a molecular biologist at the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden, Germany, is the senior author of one of the many studies investigating this family of genes. In an attempt to understand why a particular worm species regenerates its tail section but not its head piece, Rink sliced subjects apart at various positions along their bodies and sequenced the RNA collected from the wounds.

They found that in areas exhibiting regenerative capacities, the gene expression associated with the Wnt pathway was turned up. Conversely, similar expression was noticeably absent in areas that would not regrow tissue, leading the team to conclude that the regenerative capacity was somehow suppressed in these areas.

The team found that by knocking out a gene regulating Wnt function, they could turn up the regenerative gene expression and allow worms to regrow fully functional heads.

Since the Wnt genes are endemic to all animals, Rink suggests that similarly silenced abilities may exist in other species as well - and while an over-the-counter regeneration pill remains confined to science fiction, a more sophisticated understanding of its basic principle may benefit future drug research.

"What's happening here is that cells are reading their position in the body and then rebuilding the requisite structures," Aboobaker said. "That's also what happens when cells from your liver or kidney replace themselves - if we can understand those processes better, that's useful."

Source:

S.-Y. Liu, C. Selck, B. Friedrich, R. Lutz, M. Vila-Farré, A. Dahl, H. Brandl,N. Lakshmanaperumal,I. Henry & J. C. Rink. "Reactivating head regrowth in a regeneration-deficient planarian species." Nature (2013) doi:10.1038/nature12414