title: Meloidogyne javanica fatty acid- and retinol-binding protein (Mj-FAR-1) regulates expression of lipid-, cell wall-, stress- and phenylpropanoid-related genes during nematode infection of tomato.
abstract: BACKGROUND
  The secreted Meloidogyne javanica fatty acid- and retinol-binding (FAR) protein Mj-FAR-1 is involved in nematode development and reproduction in host tomato roots. To gain further insight into the role of Mj-FAR-1 in regulating disease development, local transcriptional changes were monitored in tomato hairy root lines with constitutive mj-far-1 expression compared with control roots without inoculation, and 2, 5 and 15 days after inoculation (DAI), using mRNA sequencing analysis.
  
  
  RESULTS
  Gene-expression profiling revealed a total of 3970 differentially expressed genes (DEGs) between the two lines. Among the DEGs, 1093, 1039, 1959, and 1328 genes were up- or downregulated 2-fold with false discovery rate < 0.001 in noninoculated roots, and roots 2, 5, and 15 DAI compared with control roots, respectively. Four main groups of genes that might be associated with Mj-FAR-1-mediated susceptibility were identified: 1) genes involved in biotic stress responses such as pathogen-defense mechanisms and hormone metabolism; 2) genes involved in phenylalanine and phenylpropanoid metabolism; 3) genes associated with cell wall synthesis, modification or degradation; and 4) genes associated with lipid metabolism. All of these genes were overrepresented among the DEGs. Studying the distances between the treatments, samples from noninoculated roots and roots at 2 DAI clustered predominantly according to the temporal dynamics related to nematode infection. However, at the later time points (5 and 15 DAI), samples clustered predominantly according to mj-far-1 overexpression, indicating that at these time points Mj-FAR-1 is more important in defining a common transcriptome.
  
  
  CONCLUSIONS
  The presence of four groups of DEGs demonstrates a network of molecular events is mediated by Mj-FAR-1 that leads to highly complex manipulation of plant defense responses against nematode invasion. The results shed light on the in vivo role of secreted FAR proteins in parasitism, and add to the mounting evidence that secreted FAR proteins play a major role in nematode parasitism.
authors.affiliation: Department of Entomology, Nematology and Chemistry Units, Agricultural Research Organization (ARO), Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel. sho132@gmail.com.
authors.forename: Ionit
authors.initials: I
authors.lastname: Iberkleid
authors.affiliation: Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, 76100, Israel. noa@volcani.agri.gov.il.
authors.forename: Noa
authors.initials: N
authors.lastname: Sela
authors.affiliation: Department of Entomology, Nematology and Chemistry Units, Agricultural Research Organization (ARO), Volcani Center, P.O. Box 6, Bet Dagan, 50250, Israel. sigalhor@volcani.agri.gov.il.
authors.forename: Sigal
authors.initials: S
authors.lastname: Brown Miyara
mesh_terms: D000818:Animals; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism; D015536:Down-Regulation; D050556:Fatty Acid-Binding Proteins / Q000494:pharmacology*; D059014:High-Throughput Nucleotide Sequencing; D050356:Lipid Metabolism / Q000187:drug effects / Q000235:genetics; D018551:Solanum lycopersicum / Q000187:drug effects* / Q000378:metabolism / Q000469:parasitology; D010935:Plant Diseases / Q000235:genetics / Q000469:parasitology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism / Q000469:parasitology; D025341:Principal Component Analysis; D011401:Promoter Regions, Genetic; D020005:Propanols / Q000378:metabolism; D018749:RNA, Plant / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism; D012177:Retinol-Binding Proteins / Q000494:pharmacology*; D017423:Sequence Analysis, RNA; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D014431:Tylenchoidea / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D050556:Fatty Acid-Binding Proteins; D010940:Plant Proteins; D020005:Propanols; D018749:RNA, Plant; D012177:Retinol-Binding Proteins; C439395:1-phenylpropanol