title: Defense/stress responses activated by chitosan in sycamore cultured cells.
abstract: Chitosan (CHT) is a natural, non-toxic, and inexpensive compound obtained by partial alkaline deacetylation of chitin, the main component of the exoskeleton of crustaceans and other arthropods. The unique physiological and biological properties of CHT make this polymer useful for a wide range of industries. In agriculture, CHT is used to control numerous pre- and postharvest diseases on various horticultural commodities. In recent years, much attention has been devoted to CHT as an elicitor of defense responses in plants, which include raising of cytosolic Ca(2+), activation of MAP kinases, callose apposition, oxidative burst, hypersensitive response, synthesis of abscisic acid, jasmonate, phytoalexins, and pathogenesis-related proteins. In this work, we investigated the effects of different CHT concentrations on some defense/stress responses of sycamore (Acer pseudoplatanus L.) cultured cells. CHT induced accumulation of dead cells, and of cells with fragmented DNA, production of H(2)O(2) and nitric oxide, release of cytochrome c from the mitochondrion, accumulation of regulative 14-3-3 proteins in the cytosol and of HSP70 molecular chaperone binding protein in the endoplasmic reticulum, accompanied by marked modifications in the architecture of this cell organelle.
authors.affiliation: Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, Milan, Italy. massimo.malerba@unimib.it
authors.forename: Massimo
authors.initials: M
authors.lastname: Malerba
authors.forename: Paolo
authors.initials: P
authors.lastname: Crosti
authors.forename: Raffaella
authors.initials: R
authors.lastname: Cerana
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism; D031002:Acer / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D016923:Cell Death; D002470:Cell Survival; D002478:Cells, Cultured; D048271:Chitosan / Q000494:pharmacology*; D003470:Culture Media / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D053938:DNA Fragmentation; D004591:Electrophoresis, Polyacrylamide Gel; D004721:Endoplasmic Reticulum / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D020287:In Situ Nick-End Labeling; D018613:Microscopy, Confocal; D008928:Mitochondria / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D059828:Plant Cells / Q000187:drug effects* / Q000276:immunology; D013312:Stress, Physiological
chemical_list: D048948:14-3-3 Proteins; D003470:Culture Media; D018840:HSP70 Heat-Shock Proteins; D009569:Nitric Oxide; D045304:Cytochromes c; D048271:Chitosan; D006861:Hydrogen Peroxide