title: Cell Death Control by Matrix Metalloproteinases.
abstract: In contrast to mammalian matrix metalloproteinases (MMPs) that play important roles in the remodeling of the extracellular matrix in animals, the proteases responsible for dynamic modifications of the plant cell wall are largely unknown. A possible involvement of MMPs was addressed by cloning and functional characterization of Sl2-MMP and Sl3-MMP from tomato (Solanum lycopersicum). The two tomato MMPs were found to resemble mammalian homologs with respect to gelatinolytic activity, substrate preference for hydrophobic amino acids on both sides of the scissile bond, and catalytic properties. In transgenic tomato seedlings silenced for Sl2/3-MMP expression, necrotic lesions were observed at the base of the hypocotyl. Cell death initiated in the epidermis and proceeded to include outer cortical cell layers. In later developmental stages, necrosis spread, covering the entire stem and extending into the leaves of MMP-silenced plants. The subtilisin-like protease P69B was identified as a substrate of Sl2- and Sl3-MMP. P69B was shown to colocalize with Sl-MMPs in the apoplast of the tomato hypocotyl, it exhibited increased stability in transgenic plants silenced for Sl-MMP activity, and it was cleaved and inactivated by Sl-MMPs in vitro. The induction of cell death in Sl2/3-MMP-silenced plants depended on P69B, indicating that Sl2- and Sl3-MMP act upstream of P69B in an extracellular proteolytic cascade that contributes to the regulation of cell death in tomato.
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.).
authors.forename: Dirk
authors.initials: D
authors.lastname: Zimmermann
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.).
authors.forename: Juan A
authors.identifier: 0000-0001-5310-7758
authors.initials: JA
authors.lastname: Gomez-Barrera
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.).
authors.forename: Christian
authors.identifier: 0000-0002-0244-193X
authors.initials: C
authors.lastname: Pasule
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.).
authors.forename: Ursula B
authors.identifier: 0000-0002-1100-7369
authors.initials: UB
authors.lastname: Brack-Frick
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.).
authors.forename: Elke
authors.initials: E
authors.lastname: Sieferer
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.).
authors.forename: Tim M
authors.identifier: 0000-0002-5874-7882
authors.initials: TM
authors.lastname: Nicholson
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.).
authors.forename: Jens
authors.initials: J
authors.lastname: Pfannstiel
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.).
authors.forename: Annick
authors.identifier: 0000-0002-6479-8184
authors.initials: A
authors.lastname: Stintzi
authors.affiliation: Institute of Plant Physiology and Biotechnology (D.Z., J.A.G.-B., C.P., E.S., T.M.N., A.St., A.Sc.) and Service Unit Mass Spectrometry (J.P.), University of Hohenheim, 70593 Stuttgart, Germany; andEidgenössisch Technische Hochschule Zürich, Institute of Plant Sciences, 8092 Zurich, Switzerland (U.B.B.-F.) andreas.schaller@uni-hohenheim.de.
authors.forename: Andreas
authors.identifier: 0000-0001-6872-9576
authors.initials: A
authors.lastname: Schaller
mesh_terms: D055162:Biocatalysis; D016923:Cell Death; D003001:Cloning, Molecular; D015180:Electrophoresis, Gel, Two-Dimensional; D024202:Electrophoretic Mobility Shift Assay; D018546:Hypocotyl / Q000378:metabolism; D018551:Solanum lycopersicum / Q000166:cytology* / Q000201:enzymology*; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D010641:Phenotype; D010940:Plant Proteins / Q000378:metabolism; D030821:Plants, Genetically Modified; D021381:Protein Transport; D020543:Proteome / Q000378:metabolism; D040901:Proteomics; D034622:RNA Interference; D013347:Subcellular Fractions / Q000201:enzymology; D013379:Substrate Specificity
chemical_list: D010940:Plant Proteins; D020543:Proteome; D020782:Matrix Metalloproteinases