Systems Biology of Pseudomonas syringae Type III Secretion Effector Repertoires
Magdalen Lindeberg and Alan Collmer
from: Bacteria-Plant Interactions: Advanced Research and Future Trends (Edited by: Jesús Murillo, Boris A. Vinatzer, Robert W. Jackson and Dawn L. Arnold). Caister Academic Press, U.K. (2015) Pages: 31-60.
Pseudomonas syringae defeats the two-tiered innate immune system of plants primarily with effector proteins that are injected into host cells by the type III secretion system. Although effector repertoires are remarkably diverse among P. syringae pathovars and even among strains virulent on the same host, they share several properties suggesting that effectors in a repertoire operate as components of a system. Much progress has been made in understanding the structure, function, and evolution of P. syringae effector repertoires. Multiple approaches for identifying effector genes have been applied to several sequenced reference strains and then extended to yield a tentative super-repertoire for the P. syringae species pangenome. Comparative and functional genomic studies have revealed patterns in repertoire composition and mechanisms of effector gene gain, loss, and allelic polymorphism. Substantial progress has been made in understanding the mechanisms by which effectors subvert host immunity-associated proteins. Information on P. syringae effectors is thus accumulating at multiple levels, from dynamics of gene distribution in field strains to structural biology of effector interactions with host targets. A challenge for the future is to identify vulnerabilities in the apparent robustness of effector repertoires that can be exploited for more durable crop resistance to the many diseases caused by P. syringae read more ...