But the two-pronged approach appears to be exploited by a pathogenic microbe that hijacks the cell's molecular motors to power a destructive march through its human host. The research by biochemists at UCSF is reported in the May 14 issue of the journal Cell. Regulated movement at the cellular level is critical for survival.
Cells divide, migrate toward food and away from danger.
These proteins are thought to translate selected signals into commands that engage the cell's gears of motion. The pathogenic, food-borne bacterium Listeria monocytogenes, which can cause meningitis and other serious illnesses, is known to recruit the motility apparatus of its human host cells. It uses this engine to power a rocket-like tail and propel itself along a route of infection from one cell to the next. Under normal conditions, the Enabled protein links to receptors near the cell membrane when it receives an external signal to move. Then the organizing protein recruits and mobilizes the cell's motility protein, actin.