title: Comparative transcriptional profiling of orange fruit in response to the biocontrol yeast Kloeckera apiculata and its active compounds.
abstract: BACKGROUND
  The yeast Kloeckera apiculata strain 34-9 is an antagonist that shows biological control activity against the postharvest fungal pathogens of citrus. An antifungal compound, 2-phenylethanol (PEA), has been identified from the extract of K. apiculata. To better understand the molecular processes underlying the response of citrus fruit tissue to K. apiculata, the extract and PEA, microarray analyses were performed on navel oranges using an Affymetrix Citrus GeneChip.
  
  
  RESULTS
  As many as 801, 339 and 608 differentially expressed genes (DEGs) were identified after the application of K. apiculata, the extract and PEA, respectively. In general, K. apiculata induced the expression of defence-related genes. In addition to chitinase and β-1,3-glucanase, genes involved in ethylene (ET), jasmonic acid (JA), calcium signalling, MAPK signalling and phenylalanine metabolism were induced. In contrast, monodehydroascorbate reductase, superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and carotenoid biosynthesis genes were down-regulated. The expression profiles for the extract- and PEA-treated samples were similar to that found for yeast (sharing 57.4 % DEGs), with a significant increase in the transcript levels of defence-related genes.
  
  
  CONCLUSIONS
  This study provides a global picture of the gene expression changes in navel oranges after the application of the antagonist yeast K. apiculata, its extract and PEA. The interpretation of the DEGs revealed new insight into the molecular processes that regulate the defence responses in orange tissue.
authors.affiliation: Key Laboratory of Pomology, Anhui Agricultural University, Hefei, 230036, P. R. China. puliuchina@gmail.com.|Key Laboratory of Horticultural Plant Biology of the Ministry of Education, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan, 430070, P. R. China. puliuchina@gmail.com.
authors.forename: Pu
authors.initials: P
authors.lastname: Liu
authors.affiliation: Key Laboratory of Horticultural Plant Biology of the Ministry of Education, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan, 430070, P. R. China. kadychen2015@163.com.
authors.forename: Kai
authors.initials: K
authors.lastname: Chen
authors.affiliation: Key Laboratory of Pomology, Anhui Agricultural University, Hefei, 230036, P. R. China. liguofeng0526@163.com.
authors.forename: Guofeng
authors.initials: G
authors.lastname: Li
authors.affiliation: Research Institute of Fruit and Tea, Hubei Academy of Agricultural Science, Wuhan, 430064, P. R. China. yangxiaoping1981@163.com.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Yang
authors.affiliation: Key Laboratory of Horticultural Plant Biology of the Ministry of Education, National Centre of Citrus Breeding, Huazhong Agricultural University, Wuhan, 430070, P. R. China. calong@mail.hzau.edu.cn.
authors.forename: Chao-An
authors.initials: CA
authors.lastname: Long
mesh_terms: D020013:Calcium Signaling / Q000235:genetics*; D032084:Citrus sinensis / Q000235:genetics* / Q000254:growth & development / Q000382:microbiology; D003517:Cyclopentanes / Q000378:metabolism; D005030:Ethylenes / Q000378:metabolism; D005638:Fruit / Q000235:genetics* / Q000254:growth & development; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D055322:Kloeckera / Q000187:drug effects* / Q000472:pathogenicity; D020929:Mitogen-Activated Protein Kinase Kinases / Q000235:genetics; D054883:Oxylipins / Q000378:metabolism; D010649:Phenylalanine / Q000378:metabolism; D010626:Phenylethyl Alcohol / Q000494:pharmacology
chemical_list: D003517:Cyclopentanes; D005030:Ethylenes; D054883:Oxylipins; D010649:Phenylalanine; C011006:jasmonic acid; C036216:ethylene; D020929:Mitogen-Activated Protein Kinase Kinases; D010626:Phenylethyl Alcohol