Gene expression signatures from three genetically separable resistance gene signaling pathways for downy mildew resistance.
Resistance gene-dependent disease resistance to pathogenic microorganisms is mediated by genetically separable regulatory pathways. Using the GeneChip Arabidopsis genome array, we compared the expression profiles of approximately 8,000 Arabidopsis genes following activation of three RPP genes directed against the pathogenic oomycete Peronospora parasitica. Judicious choice of P. parasitica isolates and loss of resistance plant mutants allowed us to compare the responses controlled by three genetically distinct resistance gene-mediated signaling pathways. We found that all three pathways can converge, leading to up-regulation of common sets of target genes. At least two temporal patterns of gene activation are triggered by two of the pathways examined. Many genes defined by their early and transient increases in expression encode proteins that execute defense biochemistry, while genes exhibiting a sustained or delayed expression increase predominantly encode putative signaling proteins. Previously defined and novel sequence motifs were found to be enriched in the promoters of genes coregulated by the local defense-signaling network. These putative promoter elements may operate downstream from signal convergence points.
Eulgem
Thomas
T
Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
Weigman
Victor J
VJ
Chang
Hur-Song
HS
McDowell
John M
JM
Holub
Eric B
EB
Glazebrook
Jane
J
Zhu
Tong
T
Dangl
Jeffery L
JL
D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000378:metabolism; D017124:Conserved Sequence / Q000235:genetics; D020869:Gene Expression Profiling / Q000379:methods*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D007113:Immunity, Innate / Q000235:genetics; D044742:Peronospora / Q000254:growth & development*; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology*; D015398:Signal Transduction / Q000235:genetics*; D015533:Transcriptional Activation
D029681:Arabidopsis Proteins; C107295:RPP5 protein, Arabidopsis; C488787:RPP8 protein, Arabidopsis; D002265:Carboxylic Ester Hydrolases; C400766:PAD4 protein, Arabidopsis