title: Substantial reprogramming of the Eutrema salsugineum (Thellungiella salsuginea) transcriptome in response to UV and silver nitrate challenge.
abstract: BACKGROUND
  Cruciferous plants synthesize a large variety of tryptophan-derived phytoalexins in response to pathogen infection, UV irradiation, or high dosages of heavy metals. The major phytoalexins of Eutrema salsugineum (Thellungiella salsuginea), which has recently been established as an extremophile model plant, are probably derivatives of indole glucosinolates, in contrast to Arabidopsis, which synthesizes characteristic camalexin from the glucosinolate precursor indole-3-acetaldoxime.
  
  
  RESULTS
  The transcriptional response of E. salsugineum to UV irradiation and AgNO3 was monitored by RNAseq and microarray analysis. Most transcripts (respectively 70% and 78%) were significantly differentially regulated and a large overlap between the two treatments was observed (54% of total). While core genes of the biosynthesis of aliphatic glucosinolates were repressed, tryptophan and indole glucosinolate biosynthetic genes, as well as defence-related WRKY transcription factors, were consistently upregulated. The putative Eutrema WRKY33 ortholog was functionally tested and shown to complement camalexin deficiency in Atwrky33 mutant.
  
  
  CONCLUSIONS
  In E. salsugineum, UV irradiation or heavy metal application resulted in substantial transcriptional reprogramming. Consistently induced genes of indole glucosinolate biosynthesis and modification will serve as candidate genes for the biosynthesis of Eutrema-specific phytoalexins.
authors.affiliation: Lehrstuhl für Genetik, Technische Universität München, D-85354, Freising, Germany. stefanie.mucha@wzw.tum.de.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Mucha
authors.affiliation: Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14476, Potsdam, Germany. walther@mpimp-golm.mpg.de.
authors.forename: Dirk
authors.initials: D
authors.lastname: Walther
authors.affiliation: Lehrstuhl für Genetik, Technische Universität München, D-85354, Freising, Germany. temueller@wzw.tum.de.
authors.forename: Teresa M
authors.initials: TM
authors.lastname: Müller
authors.affiliation: Max-Planck-Institut für Molekulare Pflanzenphysiologie, 14476, Potsdam, Germany. hincha@mpimp-golm.mpg.de.
authors.forename: Dirk K
authors.initials: DK
authors.lastname: Hincha
authors.affiliation: Lehrstuhl für Genetik, Technische Universität München, D-85354, Freising, Germany. egl@wzw.tum.de.
authors.forename: Erich
authors.initials: E
authors.lastname: Glawischnig
mesh_terms: D053898:Biosynthetic Pathways / Q000235:genetics; D019607:Brassicaceae / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D065150:Cellular Reprogramming / Q000187:drug effects* / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects* / Q000528:radiation effects*; D055786:Gene Knockout Techniques; D005961:Glucosinolates / Q000096:biosynthesis; D007211:Indoles / Q000378:metabolism; D019216:Metals, Heavy / Q000633:toxicity; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012717:Sesquiterpenes / Q000378:metabolism; D012835:Silver Nitrate / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D013844:Thiazoles / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects / Q000528:radiation effects; D059467:Transcriptome / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D014364:Tryptophan / Q000096:biosynthesis; D014466:Ultraviolet Rays; D000094162:Phytoalexins
chemical_list: D005961:Glucosinolates; D007211:Indoles; D019216:Metals, Heavy; D012333:RNA, Messenger; D012717:Sesquiterpenes; D013844:Thiazoles; D014157:Transcription Factors; C102405:camalexin; D014364:Tryptophan; D012835:Silver Nitrate; D000094162:Phytoalexins