These scanning electron micrographs show the two faces of the Hippo pathway – a series of proteins that control organ growth, stem cell function and tumour development. Here, the unsightly fruit fly (right) is covered in patches of cells containing a mutation in the Hippo gene encoding a key protein of the cascade. This causes the fly’s cuticle to grow uncontrollably giving it a hippopotamus-like appearance. The other fly has a normal gene and looks dandy. Defects in the Hippo pathway contribute to the development of cancer. But confusingly, when certain parts of the pathway are activated it has a beneficial role, stimulating tissue repair and regeneration after injury. Scientists hope that targeting components of the Hippo pathway with novel drugs will provide exciting new approaches for cancer treatment.
Written by Nick Kennedy
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.