XopD SUMO protease affects host transcription, promotes pathogen growth, and delays symptom development in xanthomonas-infected tomato leaves.
We demonstrate that XopD, a type III effector from Xanthomonas campestris pathovar vesicatoria (Xcv), suppresses symptom production during the late stages of infection in susceptible tomato (Solanum lycopersicum) leaves. XopD-dependent delay of tissue degeneration correlates with reduced chlorophyll loss, reduced salicylic acid levels, and changes in the mRNA abundance of senescence- and defense-associated genes despite high pathogen titers. Subsequent structure-function analyses led to the discovery that XopD is a DNA binding protein that alters host transcription. XopD contains a putative helix-loop-helix domain required for DNA binding and two conserved ERF-associated amphiphilic motifs required to repress salicylic acid- and jasmonic acid-induced gene transcription in planta. Taken together, these data reveal that XopD is a unique virulence factor in Xcv that alters host transcription, promotes pathogen multiplication, and delays the onset of leaf chlorosis and necrosis.
Kim
Jung-Gun
JG
Department of Biology, Stanford University, Stanford, California 94305, USA.
Taylor
Kyle W
KW
Hotson
Andrew
A
Keegan
Mark
M
Schmelz
Eric A
EA
Mudgett
Mary Beth
MB
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002734:Chlorophyll / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D054884:Host-Pathogen Interactions; D015151:Immunoblotting; D018551:Solanum lycopersicum / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020156:Salicylic Acid / Q000378:metabolism; D014158:Transcription, Genetic; D014974:Xanthomonas / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D002734:Chlorophyll; D020156:Salicylic Acid