title: Beneficial 'unintended effects' of a cereal cystatin in transgenic lines of potato, Solanum tuberosum.
abstract: BACKGROUND
  Studies reported unintended pleiotropic effects for a number of pesticidal proteins ectopically expressed in transgenic crops, but the nature and significance of such effects in planta remain poorly understood. Here we assessed the effects of corn cystatin II (CCII), a potent inhibitor of C1A cysteine (Cys) proteases considered for insect and pathogen control, on the leaf proteome and pathogen resistance status of potato lines constitutively expressing this protein.
  
  
  RESULTS
  The leaf proteome of lines accumulating CCII at different levels was resolved by 2-dimensional gel electrophoresis and compared with the leaf proteome of a control (parental) line. Out of ca. 700 proteins monitored on 2-D gels, 23 were significantly up- or downregulated in CCII-expressing leaves, including 14 proteins detected de novo or up-regulated by more than five-fold compared to the control. Most up-regulated proteins were abiotic or biotic stress-responsive proteins, including different secretory peroxidases, wound inducible protease inhibitors and pathogenesis-related proteins. Accordingly, infection of leaf tissues by the fungal necrotroph Botryris cinerea was prevented in CCII-expressing plants, despite a null impact of CCII on growth of this pathogen and the absence of extracellular Cys protease targets for the inhibitor.
  
  
  CONCLUSIONS
  These data point to the onset of pleiotropic effects altering the leaf proteome in transgenic plants expressing recombinant protease inhibitors. They also show the potential of these proteins as ectopic modulators of stress responses in planta, useful to engineer biotic or abiotic stress tolerance in crop plants of economic significance.
authors.affiliation: Centre de Recherche en Horticulture, Département de phytologie, Université Laval, Pavillon des Services, 2440 boul, Hochelaga, Québec, QC G1V 0A6, Canada.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Munger
authors.forename: Karine
authors.initials: K
authors.lastname: Coenen
authors.forename: Line
authors.initials: L
authors.lastname: Cantin
authors.forename: Charles
authors.initials: C
authors.lastname: Goulet
authors.forename: Louis-Philippe
authors.initials: LP
authors.lastname: Vaillancourt
authors.forename: Marie-Claire
authors.initials: MC
authors.lastname: Goulet
authors.forename: Russell
authors.initials: R
authors.lastname: Tweddell
authors.forename: Frank
authors.initials: F
authors.lastname: Sainsbury
authors.forename: Dominique
authors.initials: D
authors.lastname: Michaud
mesh_terms: D020171:Botrytis / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development; D002853:Chromatography, Liquid; D015891:Cystatins / Q000378:metabolism*; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D002523:Edible Grain / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D005110:Extracellular Space / Q000187:drug effects / Q000201:enzymology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D058685:Genetic Pleiotropy / Q000187:drug effects; D013058:Mass Spectrometry; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011480:Protease Inhibitors / Q000494:pharmacology; D020543:Proteome / Q000378:metabolism; D011198:Solanum tuberosum / Q000187:drug effects / Q000235:genetics* / Q000382:microbiology; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D015891:Cystatins; D010940:Plant Proteins; D011480:Protease Inhibitors; D020543:Proteome; C077834:cystatin protein, Zea mays