Salmonella type III secretion effectors: pulling the host cell's strings.

The enteric pathogen Salmonella employs type III secretion systems to transport a cocktail of effector proteins directly into its host cell. These effectors act in concert to control a variety of host cell processes to successfully invade intestinal cells and to establish an intracellular, replication-permissive niche. Recent studies reveal new insights into the molecular mechanisms that underlie effector protein injection, host cell invasion, and manipulation of vesicle trafficking induced by the interplay between multiple effectors and host systems. These findings corroborate the importance of spatio-temporal regulation of effector protein function for fine-tuned modulation of the host cell machinery.