title: Citrus tristeza virus (CTV) Causing Proteomic and Enzymatic Changes in Sweet Orange Variety "Westin".
abstract: Citrus Tristeza disease, caused by CTV (Citrus tristeza virus), committs citrus plantations around the world and specifically attacks phloem tissues of the plant. The virus exists as a mixture of more or less severe variants, which may or may not cause symptoms of Tristeza. The objective of this study was to analyze the changes caused by CTV in the proteome of stems of sweet orange, as well as in the activity and gene expression of antioxidant enzymes. The CTV-infected sweet orange displayed mild symptoms, which were characterized by the presence of sparse stem pitting throughout their stems. The presence of virus was confirmed by RT-PCR. Proteomic analysis by 2DE-PAGE-MS / MS revealed the identity of 40 proteins differentially expressed between CTV- infected and -non-infected samples. Of these, 33 were up-regulated and 7 were down-regulated in CTV-infected samples. Among the proteins identified stands out a specific from the virus, the coat protein. Other proteins identified are involved with oxidative stress and for this their enzymatic activity was measured. The activity of superoxide dismutase (SOD) was higher in CTV-infected samples, as catalase (CAT) showed higher activity in uninfected samples. The activity of guaiacol peroxidase (GPX) did not vary significantly between samples. However, ascorbate peroxidase (APX) was more active in the infected samples. The relative expression of the genes encoding CAT, SOD, APX and GPX was analyzed by quantitative real time PCR (RT-qPCR). The CTV-infected samples showed greater accumulation of transcripts, except for the CAT gene. This gene showed higher expression in the uninfected samples. Taken together, it can be concluded that the CTV affects the protein profile and activity and gene expression of antioxidant enzymes in plants infected by this virus.
authors.affiliation: Centro of Biotechnologia and Genetica, Universidade Estadual de Santa Cruz, UESC, Rodovia Ilhéus-Itabuna, Km 16, Ilhéus/BA, 45662-000, Brasil.
authors.forename: Milena Santos
authors.initials: MS
authors.lastname: Dória
authors.affiliation: Centro of Biotechnologia and Genetica, Universidade Estadual de Santa Cruz, UESC, Rodovia Ilhéus-Itabuna, Km 16, Ilhéus/BA, 45662-000, Brasil.
authors.forename: Aurizângela Oliveira de
authors.initials: AO
authors.lastname: Sousa
authors.affiliation: Embrapa Mandioca e Fruticultura, CEP 44380-000, Cruz das Almas, BA, Brazil.
authors.forename: Cristiane de Jesus
authors.initials: Cde J
authors.lastname: Barbosa
authors.affiliation: Centro of Biotechnologia and Genetica, Universidade Estadual de Santa Cruz, UESC, Rodovia Ilhéus-Itabuna, Km 16, Ilhéus/BA, 45662-000, Brasil.
authors.forename: Márcio Gilberto Cardoso
authors.initials: MG
authors.lastname: Costa
authors.affiliation: Embrapa Mandioca e Fruticultura, CEP 44380-000, Cruz das Almas, BA, Brazil.
authors.forename: Abelmon da Silva
authors.initials: Ada S
authors.lastname: Gesteira
authors.affiliation: Centro of Biotechnologia and Genetica, Universidade Estadual de Santa Cruz, UESC, Rodovia Ilhéus-Itabuna, Km 16, Ilhéus/BA, 45662-000, Brasil.
authors.forename: Regina Martins
authors.initials: RM
authors.lastname: Souza
authors.affiliation: Centro of Biotechnologia and Genetica, Universidade Estadual de Santa Cruz, UESC, Rodovia Ilhéus-Itabuna, Km 16, Ilhéus/BA, 45662-000, Brasil.
authors.forename: Ana Camila Oliveira
authors.initials: AC
authors.lastname: Freitas
authors.affiliation: Centro of Biotechnologia and Genetica, Universidade Estadual de Santa Cruz, UESC, Rodovia Ilhéus-Itabuna, Km 16, Ilhéus/BA, 45662-000, Brasil.
authors.forename: Carlos Priminho
authors.initials: CP
authors.lastname: Pirovani
mesh_terms: D060387:Ascorbate Peroxidases / Q000235:genetics / Q000378:metabolism; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D032084:Citrus sinensis / Q000235:genetics / Q000378:metabolism / Q000821:virology*; D017790:Closterovirus / Q000235:genetics / Q000502:physiology*; D015180:Electrophoresis, Gel, Two-Dimensional; D004798:Enzymes / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling / Q000379:methods; D018506:Gene Expression Regulation, Plant; D015967:Gene Expression Regulation, Viral; D054884:Host-Pathogen Interactions / Q000235:genetics; D009195:Peroxidase / Q000235:genetics / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics / Q000821:virology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D020543:Proteome / Q000235:genetics / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D004798:Enzymes; D010940:Plant Proteins; D020543:Proteome; C121048:guaiacol peroxidase; D060387:Ascorbate Peroxidases; D002374:Catalase; D009195:Peroxidase; D013482:Superoxide Dismutase