title: Transcriptional profiling of Zea mays roots reveals roles for jasmonic acid and terpenoids in resistance against Phytophthora cinnamomi.
abstract: Phytophthora cinnamomi is a soil-borne plant pathogen that has caused widespread damage to vulnerable native ecosystems and agriculture systems across the world and shows no sign of abating. Management of the pathogen in the natural environment is difficult and the options are limited. In order to discover more about how resistant plants are able to defend themselves against this generalist pathogen, a microarray study of plant gene expression following root inoculation with P. cinnamomi was undertaken. Zea mays was used as a resistant model plant, and microarray analysis was conducted using the Affymetrix GeneChip Maize Genome Array on root samples collected at 6- and 24-h post-inoculation. Over 300 genes were differentially expressed in inoculated roots compared with controls across the two time points. Following Gene Ontology enrichment analysis and REVIGO visualisation of the up-regulated genes, many were implicated in plant defence responses to biotic stress. Genes that were up-regulated included those involved in phytoalexin biosynthesis and jasmonic acid/ethylene biosynthesis and other defence-related genes including those encoding glutathione S-transferases and serine-protease inhibitors. Of particular interest was the identification of the two most highly up-regulated genes, terpene synthase11 (Tps11) and kaurene synthase2 (An2), which are both involved in production of terpenoid phytoalexins. This is the first study that has investigated gene expression at a global level in roots in response to P. cinnamomi in a model plant species and provides valuable insights into the mechanisms involved in defence.
authors: School of Life and Environmental Sciences, Deakin University, Geelong Campus at Waurn Ponds, Geelong, Victoria 3217, Australia.
authors: Jane Alisa
authors: JA
authors: Allardyce
authors: James Edward
authors: JE
authors: Rookes
authors: Hashmath Inayath
authors: HI
authors: Hussain
authors: David Miles
authors: DM
authors: Cahill
mesh_terms: D001315:Australia; D003517:Cyclopentanes / Q000378:metabolism*; D030541:Databases, Genetic; D060467:Disease Resistance / Q000235:genetics / Q000276:immunology; D017753:Ecosystem; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D058977:Molecular Sequence Annotation; D059372:Nucleotide Motifs / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D054883:Oxylipins / Q000378:metabolism*; D010838:Phytophthora / Q000276:immunology*; D010935:Plant Diseases / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D018517:Plant Roots / Q000166:cytology / Q000235:genetics / Q000276:immunology / Q000382:microbiology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013729:Terpenes / Q000378:metabolism*; D013997:Time Factors; D015854:Up-Regulation / Q000235:genetics; D003313:Zea mays / Q000235:genetics* / Q000276:immunology / Q000382:microbiology
chemical_list: D003517:Cyclopentanes; D054883:Oxylipins; D012333:RNA, Messenger; D013729:Terpenes; C011006:jasmonic acid