title: Polyamine catabolism is involved in response to salt stress in soybean hypocotyls.
abstract: The possible relationship between polyamine catabolism mediated by copper-containing amine oxidase and the elongation of soybean hypocotyls from plants exposed to NaCl has been studied. Salt treatment reduced values of all hypocotyl growth parameters. In vitro, copper-containing amine oxidase activity was up to 77-fold higher than that of polyamine oxidase. This enzyme preferred cadaverine over putrescine and it was active even under the saline condition. On the other hand, saline stress increased spermine and cadaverine levels, and the in vivo copper-containing amine oxidase activity in the elongation zone of hypocotyls. The last effect was negatively modulated by the addition of the copper-containing amine oxidase inhibitor N,N'-diaminoguanidine. In turn, plants treated with the inhibitor showed a significant reduction of reactive oxygen species in the elongation zone, even in the saline situation. In addition, plants grown in cadaverine-amended culture medium showed increased hypocotyl length either in saline or control conditions and this effect was also abolished by N,N'-diaminoguanidine. Taken together, our results suggest that the activity of the copper-containing amine oxidase may be partially contributing to hypocotyl growth under saline stress, through the production of hydrogen peroxide by polyamine catabolism and reinforce the importance of polyamine catabolism and hydrogen peroxide production in the induction of salt tolerance in plants.
authors.affiliation: Unidad de Biotecnología 1, Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús/Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional de General San Martín (IIB-INTECH/CONICET-UNSAM), Camino de Circunvalación Laguna, Km 6 CC 164 (B7130IWA), Chascomús, Argentina.
authors.forename: María Paula
authors.initials: MP
authors.lastname: Campestre
authors.forename: Cesar Daniel
authors.initials: CD
authors.lastname: Bordenave
authors.forename: Andrea Cecilia
authors.initials: AC
authors.lastname: Origone
authors.forename: Ana Bernardina
authors.initials: AB
authors.lastname: Menéndez
authors.forename: Oscar Adolfo
authors.initials: OA
authors.lastname: Ruiz
authors.forename: Andrés Alberto
authors.initials: AA
authors.lastname: Rodríguez
authors.forename: Santiago Javier
authors.initials: SJ
authors.lastname: Maiale
mesh_terms: D006631:Amine Oxidase (Copper-Containing) / Q000378:metabolism*; D015870:Gene Expression; D006146:Guanidines / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000378:metabolism; D018546:Hypocotyl / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D011073:Polyamines / Q000378:metabolism*; D011188:Potassium / Q000032:analysis; D017382:Reactive Oxygen Species / Q000378:metabolism; D054712:Salinity; D055051:Salt-Tolerant Plants / Q000378:metabolism; D012492:Salts / Q000378:metabolism*; D012964:Sodium / Q000032:analysis; D013025:Glycine max / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: D006146:Guanidines; D011073:Polyamines; D017382:Reactive Oxygen Species; D012492:Salts; C070130:diaminoguanidine; D012964:Sodium; D006861:Hydrogen Peroxide; D006631:Amine Oxidase (Copper-Containing); D011188:Potassium