title: Secretome analysis of the rice bacterium Xanthomonas oryzae (Xoo) using in vitro and in planta systems.
abstract: Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight disease in rice, and that severely affects yield loss (upto 50%) of total rice production. Here, we report a proteomics investigation of Xoo (compatible race K3)-secreted proteins, isolated from its in vitro culture and in planta infected rice leaves. 2DE coupled with MALDI-TOF-MS and/or nLC-ESI-MS/MS approaches identified 139 protein spots (out of 153 differential spots), encoding 109 unique proteins. Identified proteins belonged to multiple biological and molecular functions. Metabolic and nutrient uptake proteins were common up to both in vitro and in planta secretomes. However, pathogenicity, protease/peptidase, and host defense-related proteins were highly or specifically expressed during in planta infection. A good correlation was observed between protein and transcript abundances for nine proteins secreted in planta as per semiquantitative RT-PCR analysis. Transgenic rice leaf sheath (carrying PBZ1 promoter::GFP cell death reporter), when used to express a few of the identified secretory proteins, showed a direct activation of cell death signaling, suggesting their involvement in pathogenicity related with secretion effectors. This work furthers our understanding of rice bacterial blight disease, and serves as a resource for possible translation in generating disease resistant rice plants for improved seed yield.
authors.affiliation: Plant Molecular Biology & Biotechnology Research Center, Gyeongsang National University, Jinju, South Korea.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Wang
authors.forename: Sang Gon
authors.initials: SG
authors.lastname: Kim
authors.forename: Jingni
authors.initials: J
authors.lastname: Wu
authors.forename: Hyun-Hye
authors.initials: HH
authors.lastname: Huh
authors.forename: Su-Ji
authors.initials: SJ
authors.lastname: Lee
authors.forename: Randeep
authors.initials: R
authors.lastname: Rakwal
authors.forename: Ganesh Kumar
authors.initials: GK
authors.lastname: Agrawal
authors.forename: Zee-Yong
authors.initials: ZY
authors.lastname: Park
authors.forename: Kyu
authors.initials: K
authors.lastname: Young Kang
authors.forename: Sun Tae
authors.initials: ST
authors.lastname: Kim
mesh_terms: D001426:Bacterial Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D019295:Computational Biology; D015180:Electrophoresis, Gel, Two-Dimensional; D054884:Host-Pathogen Interactions; D013058:Mass Spectrometry; D012275:Oryza / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology; D010940:Plant Proteins / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000382:microbiology*; D014974:Xanthomonas / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D010940:Plant Proteins
keywords: 2DE; MS; Plant proteomics; Rice; Secretome; Xanthomonas oryzae