deletions in the repertoire of pseudomonas syringae pv. tomato dc3000 type iii secretion effector genes reveal functional overlap among effectors删除在丁香假单胞菌的曲目。.pdfVIP

Deletions in the Repertoire of Pseudomonas syringae pv. tomato DC3000 Type III Secretion Effector Genes Reveal Functional Overlap among Effectors 1 1 ´ ´ 2 1¤ 1 Brian H. Kvitko , Duck Hwan Park , Andre C. Velasquez , Chia-Fong Wei , Alistair B. Russell , Gregory B. 1,2 1,3 1 Martin , David J. Schneider , Alan Collmer * 1 Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, United States of America, 2 Boyce Thompson Institute for Plant Research, Ithaca, New York, United States of America, 3 United States Department of Agriculture–Agricultural Research Service, Robert W. Holley Center for Agriculture and Health, Ithaca, New York, United States of America Abstract The c-proteobacterial plant pathogen Pseudomonas syringae pv. tomato DC3000 uses the type III secretion system to inject ca. 28 Avr/Hop effector proteins into plants, which enables the bacterium to grow from low inoculum levels to produce bacterial speck symptoms in tomato, Arabidopsis thaliana, and (when lacking hopQ1-1) Nicotiana benthamiana. The effectors are collectively essential but individually dispensable for the ability of the bacteria to defeat defenses, grow, and produce symptoms in plants. Eighteen of the effector genes are clustered in six genomic islands/islets. Combinatorial deletions involving these clusters and two of the remaining effector genes revealed a redundancy-based structure in the effector repertoire, such that some deletions diminished growth in N. benthamiana only in combination with other deletions. Much of the ability of DC3000 to grow in N. benthamiana was found to