title: Arabidopsis thaliana defense response to the ochratoxin A-producing strain (Aspergillus ochraceus 3.4412).
abstract: OTA-producing strain Aspergillus ochraceus induced necrotic lesions, ROS accumulation and defense responses in Arabidopsis . Primary metabolic and defense-related proteins changed in proteomics. Ascorbate-glutathione cycle and voltage-dependent anion-selective channel proteins fluctuated. Mycotoxigenic fungi, as widespread contaminants by synthesizing mycotoxins in pre-/post-harvest infected plants and even stored commercial cereals, could usually induce plant-fungi defense responses. Notably, ochratoxin A (OTA) is a nephrotoxic, hepatotoxic, teratogenic, immunotoxic and phytotoxic mycotoxin. Herein, defense responses of model system Arabidopsis thaliana detached leaves to infection of Aspergillus ochraceus 3.4412, an OTA high-producing strain, were studied from physiological, proteomic and transcriptional perspectives. During the first 72 h after inoculation (hai), the newly formed hypersensitive responses-like lesions, decreased chlorophyll content, accumulated reactive oxygen species and upregulated defense genes expressions indicated the defense response was induced in the leaves with the possible earlier motivated jasmonic acid/ethylene signaling pathways and the later salicylic acid-related pathway. Moreover, proteomics using two-dimensional gel electrophoresis 72 hai showed 16 spots with significantly changed abundance and 13 spots corresponding to 12 unique proteins were successfully identified by MALDI-TOF/TOF MS/MS. Of these, six proteins were involved in basic metabolism and four in defense-related processes, which included glutathione-S-transferase F7, voltage-dependent anion-selective channel protein 3 (VDAC-3), osmotin-like protein OSM34 and blue copper-binding protein. Verified from proteomic and/or transcriptional perspectives, it is concluded that the primary metabolic pathways were suppressed with the ascorbate-glutathione cycle fluctuated in response to A. ochraceus and the modulation of VDACs suggested the possibility of structural damage and dysfunction of mitochondria in the process. Taken together, these findings exhibited a dynamic overview of the defense responses of A. thaliana to A. ochraceus and provided a better insight into the pathogen-resistance mechanisms in plants.
authors: Laboratory of Food Safety and Molecular Biology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, 100083, People's Republic of China.
authors: Junran
authors: J
authors: Hao
authors: Weihong
authors: W
authors: Wu
authors: Yan
authors: Y
authors: Wang
authors: Zhuojun
authors: Z
authors: Yang
authors: Yang
authors: Y
authors: Liu
authors: Yangjun
authors: Y
authors: Lv
authors: Yanan
authors: Y
authors: Zhai
authors: Jing
authors: J
authors: Yang
authors: Zhihong
authors: Z
authors: Liang
authors: Kunlun
authors: K
authors: Huang
authors: Wentao
authors: W
authors: Xu
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001235:Aspergillus ochraceus / Q000737:chemistry / Q000502:physiology*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D003517:Cyclopentanes / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant; D009793:Ochratoxins / Q000378:metabolism*; D054883:Oxylipins / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000235:genetics / Q000276:immunology / Q000502:physiology; D040901:Proteomics; D017382:Reactive Oxygen Species / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D003517:Cyclopentanes; D009793:Ochratoxins; D054883:Oxylipins; D010937:Plant Growth Regulators; D017382:Reactive Oxygen Species; C023548:copper-binding protein; D002734:Chlorophyll; C025589:ochratoxin A; C011006:jasmonic acid; D020156:Salicylic Acid