Wounds prompt flatworms to regrow missing body parts

Planarian flatworms have two genes that respond to injury - Smed-follistatin (fst) and Smed-activin-1 and -2 - and in the event of a severe injury, such as an amputation, fst levels rise which then inhibit activin proteins.

This allows tissue at the injured site to regenerate without affecting normal maintenance and cell turnover in other parts of the body.

Read more at Whitehead Institute for Biomedical Research