Functions of the Yersinia effector proteins in inhibiting host immune responses

The invasion strategies used by Yersinia species involve the `hijacking' of host cellular signaling pathways, often involving microbial gene products that mimic the functions of the cellular proteins. Yersinia uses a type III secretion system to inject these microbial gene products, referred to as Yersinia effector proteins, into the host cytosol. Yersinia effector proteins can inhibit the host immune system through a diverse array of mechanisms including inhibition of the inflammatory response by interfering with cytokine production, inhibition of phagocytosis by disrupting the actin cytoskeleton, induction of apoptosis in macrophages and through the formation of novel signaling complexes.