Harvard Study Discovers Genes That Control Regeneration In Worms

Some of the creatures in the animal kingdom have incredible abilities to regenerate parts of their bodies. Salamanders, for instance, can regrow a leg if one is cut off. Some creatures have even more astonishing regeneration capability. Jellyfish, for example, can regenerate their bodies after being cut in half.

Harvard scientists have been studying these creatures in an effort to discover the DNA switches that control the genes for whole-body regeneration. The study looked into three-banded panther worms and found a section of noncoding DNA that controls the activation of a "master control gene" that is called early growth response or EGR.

When EGR is active, it controls many other processes that turn other genes on or off. EGR essentially turns on and activates other genes that are on during regeneration. The regeneration process involves the DNA in the worm's cells that are usually folded tightly to change for activation. Scientists say that portions usually very tightly packed become more open.

The researchers say that a lot of the tightly packed portions of the genome open during regeneration. Researchers had to assemble the genome sequence of the worm before they could understand how its genome changes with regeneration.

This marks the first time that the full genome sequence has been available for this species. So far as many as 18,000 regions in the genome have been identified as changing during regeneration. Interestingly the EGR master gene and other genes turned on and off during regeneration are present in other species, including humans. The trick is figuring out why EGR activates the genes in the worms that leads to regeneration and why it is unable to activate those processes in humans.