The Pto kinase conferring resistance to tomato bacterial speck disease interacts with proteins that bind a cis-element of pathogenesis-related genes.
In tomato, the Pto kinase confers resistance to bacterial speck disease by recognizing the expression of a corresponding avirulence gene, avrPto, in the pathogen Pseudomonas syringae pv. tomato. Using the yeast two-hybrid system, we have identified three genes, Pti4, Pti5 and Pti6, that encode proteins that physically interact with the Pto kinase. Pti4/5/6 each encode a protein with characteristics that are typical of transcription factors and are similar to the tobacco ethylene-responsive element-binding proteins (EREBPs). Using a gel mobility-shift assay, we demonstrate that, similarly to EREBPs, Pti4/5/6 specifically recognize and bind to a DNA sequence that is present in the promoter region of a large number of genes encoding 'pathogenesis-related' (PR) proteins. Expression of several PR genes and a tobacco EREBP gene is specifically enhanced upon Pto-avrPto recognition in tobacco. These observations establish a direct connection between a disease resistance gene and the specific activation of plant defense genes.
Zhou
J
J
Department of Agronomy, Purdue University, West Lafayette, IN 47907-1150, USA.
Tang
X
X
Martin
G B
GB
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D017343:Genes, Plant; D018551:Solanum lycopersicum; D008954:Models, Biological; D008969:Molecular Sequence Data; D005810:Multigene Family; D010935:Plant Diseases / Q000235:genetics*; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D010947:Plants, Toxic; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011549:Pseudomonas / Q000472:pathogenicity; D012045:Regulatory Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D014026:Nicotiana; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D004268:DNA-Binding Proteins; D010940:Plant Proteins; C106895:Pti4 protein, Lycopersicon esculentum; C106896:Pti5 protein, Lycopersicon esculentum; C106897:Pti6 protein, Lycopersicon esculentum; D014157:Transcription Factors; C053376:pathogenesis-related proteins, plant; C093680:ethylene-responsive element binding protein; C084354:Pto protein, Lycopersicon; D017346:Protein Serine-Threonine Kinases