In the cell, there are many proteins that function in several different processes. Two of these proteins are caspase-8 and Rab5. Caspase-8 is primarily known for its role in promoting apoptosis (programmed cell death), while Rab5 is known for its involvement in endocytosis. A paper early this year reveals that Rab5 functions downstream of an activated caspase-8 signal to alter adhesion and migration of a cell. Images above show colocalization of Rab5 (red) and actin (blue) at membrane ruffles of migrating cells expressing caspase-8 (bottom), compared to control cells (top).
Reference: Vicente A. Torres, Ainhoa Mielgo, Simone Barbero, Ruth Hsiao, John A. Wilkins, and Dwayne G. Stupack. Authors’ Molecular Biology of the Cell paper can be found here.