title: Pseudomonas syringae type III effector HopZ1 targets a host enzyme to suppress isoflavone biosynthesis and promote infection in soybean.
abstract: Type III secreted effectors (T3SEs), such as Pseudomonas syringae HopZ1, are essential bacterial virulence proteins injected into the host cytosol to facilitate infection. However, few direct targets of T3SEs are known. Investigating the target(s) of HopZ1 in soybean, a natural P. syringae host, we find that HopZ1 physically interacts with the isoflavone biosynthesis enzyme, 2-hydroxyisoflavanone dehydratase (GmHID1). P. syringae infection induces gmhid1 expression and production of daidzein, a major soybean isoflavone. Silencing gmhid1 increases susceptibility to P. syringae infection, supporting a role for GmHID1 in innate immunity. P. syringae expressing active but not the catalytic mutant of HopZ1 inhibits daidzein induction and promotes bacterial multiplication in soybean. HopZ1-enhanced P. syringae multiplication is at least partially dependent on GmHID1. Thus, GmHID1 is a virulence target of HopZ1 to promote P. syringae infection of soybean. This work highlights the isoflavonoid biosynthesis pathway as an antibacterial defense mechanism and a direct T3SE target.
authors.affiliation: Department of Plant Pathology and Microbiology, University of California, Riverside, Riverside, CA 92521, USA; Center for Plant Cell Biology, University of California, Riverside, Riverside, CA 92521, USA; Institute for Integrative Genomic Biology, University of California, Riverside, Riverside, CA 92521, USA.
authors.forename: Huanbin
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Environmental Toxicology Graduate Program, University of California, Riverside, Riverside, CA 92521, USA.
authors.forename: Jian
authors.initials: J
authors.lastname: Lin
authors.affiliation: Center for Plant Cell Biology, University of California, Riverside, Riverside, CA 92521, USA.
authors.forename: Aimee
authors.initials: A
authors.lastname: Johnson
authors.affiliation: Department of Plant Pathology and Microbiology, University of California, Riverside, Riverside, CA 92521, USA; Center for Plant Cell Biology, University of California, Riverside, Riverside, CA 92521, USA; Institute for Integrative Genomic Biology, University of California, Riverside, Riverside, CA 92521, USA.
authors.forename: Robyn L
authors.initials: RL
authors.lastname: Morgan
authors.affiliation: Environmental Toxicology Graduate Program, University of California, Riverside, Riverside, CA 92521, USA; Department of Chemistry, University of California, Riverside, Riverside, CA 92521, USA.
authors.forename: Wenwan
authors.initials: W
authors.lastname: Zhong
authors.affiliation: Department of Plant Pathology and Microbiology, University of California, Riverside, Riverside, CA 92521, USA; Center for Plant Cell Biology, University of California, Riverside, Riverside, CA 92521, USA; Institute for Integrative Genomic Biology, University of California, Riverside, Riverside, CA 92521, USA. Electronic address: wenbo.ma@ucr.edu.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Ma
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D054884:Host-Pathogen Interactions; D006836:Hydro-Lyases / Q000378:metabolism; D007529:Isoflavones / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D008856:Microscopy, Fluorescence; D009154:Mutation; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D044224:Pseudomonas syringae / Q000201:enzymology / Q000472:pathogenicity*; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D013025:Glycine max / Q000201:enzymology / Q000276:immunology / Q000382:microbiology*; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques; D015854:Up-Regulation; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D007529:Isoflavones; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D037521:Virulence Factors; C004742:daidzein; D006836:Hydro-Lyases