title: A multicomponent, elicitor-inducible cystatin complex in tomato, Solanum lycopersicum.
abstract: We assessed the ability of the fungal elicitor arachidonic acid to induce cystatin genes in tomato (Solanum lycopersicum), using a cDNA expression library from arachidonate-treated leaves. The cDNAs of two novel cystatins were isolated, coding for an approx. 11-kDa protein, SlCYS10; and for a 23.6-kDa protein, SlCYS9, bearing an N-terminal signal peptide and a long, 11.5-kDa extension at the C terminus. Both genes were induced by arachidonate but not by methyl jasmonate, an inducer of the 88-kDa eight-unit cystatin, multicystatin, accumulated in the cytosol of leaf cells upon herbivory. A truncated form of SlCYS9, tSlCYS9, was produced by deletion of the C-terminal extension to assess the influence of this structural element on the cystatin moiety. As shown by kinetic and stability assays with recombinant variants expressed in Escherichia coli, deleting the extension influenced both the overall stability and inhibitory potency of SlCYS9 against cysteine proteases of herbivorous organisms. These findings provide evidence for a multicomponent elicitor-inducible cystatin complex in tomato, including at least 10 cystatin units produced via two metabolic routes.
authors.affiliation: Département de phytologie, CRH/INAF, Université Laval, Québec, Canada G1K 7P4.
authors.forename: Cécile
authors.initials: C
authors.lastname: Girard
authors.affiliation: Département de phytologie, CRH/INAF, Université Laval, Québec, Canada G1K 7P4.
authors.forename: Daniel
authors.initials: D
authors.lastname: Rivard
authors.affiliation: Forestry and Agricultural Biotechnology Institute, Botany Department, University of Pretoria, Pretoria 0002, South Africa.
authors.forename: Andrew
authors.initials: A
authors.lastname: Kiggundu
authors.affiliation: Forestry and Agricultural Biotechnology Institute, Botany Department, University of Pretoria, Pretoria 0002, South Africa.
authors.forename: Karl
authors.initials: K
authors.lastname: Kunert
authors.affiliation: Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada K1A 0C6.
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Gleddie
authors.affiliation: Département de biologie, Centre de recherche en horticulture, Université Laval, Québec QC, Canada G1K 7P4.
authors.forename: Conrad
authors.initials: C
authors.lastname: Cloutier
authors.affiliation: Département de phytologie, CRH/INAF, Université Laval, Québec, Canada G1K 7P4.
authors.forename: Dominique
authors.initials: D
authors.lastname: Michaud
mesh_terms: D000085:Acetates / Q000494:pharmacology*; D000595:Amino Acid Sequence; D001095:Arachidonic Acids / Q000494:pharmacology*; D001483:Base Sequence; D003517:Cyclopentanes / Q000494:pharmacology*; D015891:Cystatins / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D015853:Cysteine Proteinase Inhibitors / Q000235:genetics / Q000494:pharmacology; D018076:DNA, Complementary; D018744:DNA, Plant; D017353:Gene Deletion; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D018745:Genome, Plant; D018551:Solanum lycopersicum / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes / Q000235:genetics / Q000378:metabolism; D054883:Oxylipins; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D016415:Sequence Alignment
chemical_list: D000085:Acetates; D001095:Arachidonic Acids; D003517:Cyclopentanes; D015891:Cystatins; D015853:Cysteine Proteinase Inhibitors; D018076:DNA, Complementary; D018744:DNA, Plant; D046912:Multiprotein Complexes; D054883:Oxylipins; D011994:Recombinant Proteins; C072239:methyl jasmonate