INVESTIGADORES
ORDOÑEZ Maria victoria
congresos y reuniones científicas
Título:
Heat-Shock Increases the Activity of the Germin-like Poretease Inhibitor of Wheat Leaf Apoplast
Autor/es:
MANSILLA AY; ORDOÑEZ MV; SEGARRA CI; CONDE RD
Lugar:
Mar del Plata, Pcia Buenos Aires, Argentina
Reunión:
Congreso; XLIII Reunion Annual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2007
Institución organizadora:
Sociedad Argentina de Investigación en Bioquímica y Biología Molecular
Resumen:
Previously, we found that leaf apoplast serine proteases take part in the wheat defence against the pathogenic fungus Septoria tritici. Their action either increases or decreases after inoculation with the fungus to plants of cultivars either resistant or susceptible to septoriosis, respectively. Also, we proved that these behaviours depend on the presence of an inhibitor, which was purified and partially sequenced. Its N-term sequence is homologous with germin-like proteins, being the first Germin Serine Protease Inhibitor (GPI) found. Its C-term was also determined by HPLCMS/MS. To know more about the control of its expression, the effect of high temperatures was explored. For it, 12d seedlings of the susceptible cv. ProINTA Molinero were put under 40ºC for 1, 2, 3 and 4 hours. After 3 hours, GPI activity increased ~30 %, while proteolytic activity decreased ~40%. These results suggest a link between GPI activation and heat-shock proteins induction (McElwain & Spiker. Plant Physiol 99: 1455, 1992). Also, whether GPI gene transcription changes under heat-shock or other stresses exist is explored. Thus, to earn GPI cDNA, primers based on its Nterm and C- term sequences were prepared. The cDNA that encodes for GPI was isolated by RT-PCR and is used in Northern blot essays. Supported by UNMdP, ANPCyT, CONICET, CIC BsAs.