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Domingues,Sarah J.S.; Souza,Thiago F. de; Soares,Alexandra M.S.; Jacinto,Tânia; Machado,Olga L.T.. |
In order to investigate the defense response in castor bean (Ricinus communis) against predators, we analyzed the effect of mechanical wounding upon the phospholipase A2 (PLA2) activity of leaf extracts. Time course experiments revealed that the highest levels of increased PLA2 activity (ca. two fold) occurred 15 min and 60 min after injury. The induced activities demonstrated high sensitivity towards aristolochic acid (10 mM), a PLA2 inhibitor. Based on SDS-PAGE analysis, the PLA2 activity induced 15 min after wounding migrated with a molecular mass of 40 kDa and was denoted RcPLA2 I. The protein activity induced 60 min after wounding, RcPLA2 II, migrated with a molecular weight of 14 kDa. Furthermore its N-terminal sequence shared homology with PLA2 from... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cellular defense; Castor bean; Plant signaling; Phospholipase A2; Ricinus communis. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000100004 |
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Soares,Alexandra Martins dos Santos; Souza,Thiago Freitas de; Jacinto,Tânia; Machado,Olga Lima Tavares. |
Jasmonates are a class of plant hormones that mediate various aspects in gene and metabolic regulation, defense, stress responses, reproduction and, possibly, communication. Oxidative stress stimulates synthesis of antioxidant metabolites and enhances antioxidant enzyme activities that could protect plant tissues. The aim of this study was to verify the effects of methyl jasmonate (JAME) treatment on the reactive oxygen species (ROS) and on the activities of H2O2 scavenging enzymes, such as superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6), ascorbate peroxidase (APX EC; 1.11.1.1), and guaiacol peroxidase (GPX; EC 1.11.1.7) in Ricinus communis leaves. The activity of CAT and GPX was transient while SOD activity decreased and APX increased... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Methyl jasmonate; Oxidative stress; Antioxidant enzymatic defenses; Catalase; Superoxide dismutase; Peroxidase; Ricinus comunnis; Signal transduction. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000300001 |
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